Science Science for for South South Africa Africa
ISSN 1729-830X ISSN 1729-830X
Our changing oceans South Africa's role in monitoring
Robots in the ocean the global ocean observing system Zooplankton new approaches to its study
Volume 9 • Number 1 • 2013 Volume 3 • Number 2 • 2007 R29.95 R20
INVASIVE ALIENS an Antarctic problem SEALS – high in the Southern Ocean food chain
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Cover stories
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Our changing oceans Isabelle Ansorge and Mike Roberts explain South Africa’s role in investigating the changes 6
Robots in the ocean Thomas Mtsonti and Isabelle Ansorge explain the global ocean observing system
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New ways to study zooplankton Innovation has changed our understanding of this vital link in the ocean’s food chains. By Margaux Noyon
Contents Volume 9 • Number 1 • 2013
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Invasive aliens in Antarctica Even the remote Antarctic continent has problems with invasive alien species. By Anne M Treasure
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High in the food chain – seals in the Southern Ocean Three decades of research have given scientists a lot of insight into the importance of seals in the Southern Ocean. By Cheryl Tosh and Marthán Bester
Features
Regulars 10
A swirly world – measuring ocean currents from the new SA Agulhas II Tammy Morris, Isabelle Ansorge and Patrick Vianello explain the importance of understanding ocean currents
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Careers Everything from becoming a ship’s captain to becoming a ship’s electrical engineer
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Fact file Prokaryotes and eukaryotes – p. 22
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Gliders in the ocean Africa’s first ocean gliders navigate the turbid and remote Antarctic waters. By Seb Swart
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Microbes in the ocean
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Books
54
Subscription
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Back page science • Mathematics puzzle
Gerda du Plessis introduces us to microscopic plankton
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Life at sea Christopher Jacobs, Jennifer Butler, Mokete Kaogo, Alistair Blair and Marcel du Plessis give an honours student’s perspective on life on the SA Agulhas II
Quest 9(1) 2013 1
Science Science for for South South AfricA AfricA
ISSN 1729-830X ISSN 1729-830X
Volume 9 • Number 1 • 2013 Volume 3 • Number 2 • 2007 r29.95 r20
Our changing oceans South Africa's role in monitoring
Robots in the ocean the global ocean observing system Zooplankton new approaches to its study
INVASIVE ALIENS an Antarctic problem SEALS – high in the Southern Ocean food chain
Sc A c AAcdAedmeym yo fo fS c I eI eNNccee ooff SS o u u tt hh AAffrrI c I cA A
Images: Franck Prejger; Anne Treasure; SAEON; Nico de Bruyn SCIENCE FOR SOUTH AFRICA
ISSN 1729-830X
Editor Dr Bridget Farham Editorial Board Roseanne Diab (University of KwaZulu-Natal) (Chair) John Butler-Adam (South African Journal of Science) Anusuya Chinsamy-Turan (University of Cape Town) Neil Eddy (Wynberg Boys High School) George Ellis (University of Cape Town) Kevin Govender (SAAO) Himla Soodyall (University of Witwatersrand) Penny Vinjevold (Western Cape Education Department) Correspondence and The Editor enquiries PO Box 663, Noordhoek 7979 Tel.: (021) 789 2331 Fax: 0866 718022 e-mail: ugqirha@iafrica.com (For more information visit www.questinteractive.co.za) Advertising enquiries Barbara Spence Avenue Advertising PO Box 71308 Bryanston 2021 Tel.: (011) 463 7940 Fax: (011) 463 7939 Cell: 082 881 3454 e-mail: barbara@avenue.co.za Subscription enquiries Patrick Nemushungwa (012) 349 6624 and back issues Tel.: e-mail: Patrick@assaf.org.za Copyright © 2012 Academy of Science of South Africa
Published by the Academy of Science of South Africa (ASSAf) PO Box 72135, Lynnwood Ridge 0040, South Africa Permissions Fax: 0866 718022 e-mail: ugqirha@iafrica.com
Science on the move
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he theme of this year’s SciFest Africa is ‘science on the move’ and this issue of Quest certainly reflects this. This bumper issue covers a small fraction of the exciting research that is going on in the Southern Ocean, on the sub-Antarctic islands and on the Antarctic continent itself. Understanding the dymanics – physical and biological – of the world’s oceans is vital to understanding the planet as a whole. This is particularly true when we consider our changing climate and the long-term effects that this will have on us all. Much of this research depends on our new oceanographic research ship, the SA Agulhas II, which was commissioned last year. This state-of-the art vessel will make a big difference to South Africa’s position in research on the vast and dynamic Southern Ocean. Because the bulk of the planet’s land mass is in the northern hemisphere, the Southern Ocean is particularly important to the southern hemisphere – unimpeded by land masses, the currents are circumpolar – with all the implications that this has for movement of water, water temperatures and salinity and the effects of these factors on the living components of the ocean and on our climate. The research that is taking place in this region is fast moving – often dependent on new technology – and comprehensive, from physical oceanography to Antarctic biology. The opportunities for study and future careers are almost endless – encompassing a wide range of skills and backgrounds. At the core of all these potential careers is a thorough understanding of science, and this starts at school. This issue of Quest is intended to excite your interest in science and show you just how far science can take you – truly ‘science on the move’.
Bridget Farham Editor – QUEST: Science for South Africa
IMPORTANT NOTICE TO QUEST READERS From March 2013 (Quest Vol 9/1) the distribution model of Quest will change to ensure optimum reach and greater reader satisfaction. If you want to keep on receiving your copy of Quest, kindly fill in your particulars below and post, fax or email to: Quest MAGAZINE, PO Box 72135, Lynnwood Ridge 0040, Pretoria, South Africa. Fax: 086 576 9519, Email: patrick@assaf.org.za
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South Africa • Individuals/Institutions – R100.00 • Students/schoolgoers – R50.00
Design and layout Creating Ripples Graphic Design Illustrations James Whitelaw Printing Paradigm
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All material is strictly copyright and all rights are reserved. Reproduction without permission is forbidden. Every care is taken in compiling the contents of this publication, but we assume no responsibility for effects arising therefrom. The views expressed in this magazine are not necessarily those of the publisher.
Above: Figure 1: A diagram showing the overturning circulation of the global ocean. Within the Atlantic Ocean, the circulation carries warm surface waters (red arrows) northwards and cold deep waters (blue arrows) southwards. Image: NASA/JPL-Caltech
Left: Figure 2: The Southern Ocean acts as a huge merrygo-round transporting water masses into and out of the Antarctic region. The colours represent the depths of water with red being surface, blue is for the bottom and green/ yellow represent water moving between 1000 and 3000 m Image: Lumpkin and Speer, 2007
Our changing oceans T heat, freshwater and carbon dioxide between ocean basins. This circulation also connects the surface ocean and atmosphere with the huge reservoir of the deep sea (Figure 1). The physical structure of this circulation belt and its efficiency in regulating climate are influenced significantly by the way that water masses are exchanged between ocean basins. Climate models have predicted that increased levels of greenhouse gases may interfere with the MOC process by disrupting or slowing down the circulation. One impact of
The world’s oceans are undergoing significant changes – seen in indicators such as temperature and salinity. Isabelle Ansorge and Mike Roberts explain how South African scientists are involved in investigating the state of these changes.
▲ ▲
he Meridional Overturning Circulation (MOC) is a system of surface and deep ocean currents that extend across the globe. It is the main pathway in which warm and salty surface waters from the tropics are transported polewards. In the North Atlantic Ocean, the water cools and sinks to great depths, flowing southwards as a deep (>2 000 m) ocean current in a process that is called ‘overturning’. In this way, water is returned to lower latitudes. The MOC provides a mechanism for the large-scale ocean circulation of
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Figure 3: A diagram showing the research south of Africa currently underway by researchers from the Oceanography Department at the University of Cape Town and the Oceans and Coasts Division of the Department of Environmental Affairs. The coloured circles represent regions where there is large oceanic variability in the form of ocean eddies and Agulhas rings, the yellow line represents current ship-based monitoring transects, while the various symbols represent proposed moorings. White boxes highlight areas of current and future research programmes. The aim of SAMOC-South Africa (SAMOC-SA) is to co-ordinate all the current observations into a single programme – an SKA of the oceans!
continued warming is the threat of increased melting of Greenland’s ice cap, which may result in an influx of cold and fresh surface waters into the North Atlantic Ocean. Some scientists predict that the increase in fresh water may be enough to change the composition and flow of ocean water on time scales from decades to centuries.
We know that the MOC provides a vehicle connecting surface and deep ocean currents around the world’s oceans but little is known of the response and degree in which heat is being taken up by the deep oceans. Because of this lack of knowledge, the scientific community is slowly realising that deep ocean measurements across ocean basins are crucial if we want
to reduce the uncertainties in model projections of global warming. Essentially this means that, in order to track the evolving ocean inventory of heat, freshwater and carbon dioxide, measurements need to be taken below 2 000 m. Argo floats, gliders and satellite remote sensing have revolutionised our ability to measure the upper layers of the ocean, but the deep ocean is currently beyond their reach. It is becoming more and more obvious that there is a close relationship between the deep ocean and climate, so observations need to extend below 2 000 m. However, the main obstacle is the depth of the seafloor (often over 5 km away!) and conditions this deep are often very difficult to monitor, particularly in the Southern Ocean. Currently, there is only one system monitoring the MOC and this is in the North Atlantic: the RAPID/MOCHA array located at 26.5˚N. Because the MOC covers the world’s oceans it is obvious that changes happening between the South and North Atlantic sectors must be considered in tandem. The importance of the Southern Ocean The Southern Ocean includes southern sectors of the Indian, Atlantic and Pacific basins and provides a link
Career opportunities The state of observations and modelling south of Africa is not as developed as it is in other regions of the world’s oceans. This is largely due to limited ship availability, the lack of available technical support and the lack of sufficient funds to establish a mooring array. As a result South Africa’s role in the international framework of SAMOC has been limited to studies that take place during annual relief voyages into the Southern Ocean. SAMOC-South Africa (SAMOC-SA) provides the necessary tool to pull these surveys into a single entity. This programme provides future opportunities for all young, early career and established researchers working in the South Atlantic and Southern Ocean to interact and strengthen international and national networks through a set of joint cruise plans. It will provide young students with a variety of bursaries as well as many cruise opportunities on the new SA Agulhas II and will form a crucial role in developing skills, knowledge and expertise of the area – a critical component if South Africa is to retain topclass marine scientists. The planning of a long term observational platform across the entire South Atlantic (Figure 3) takes time, but is currently being coordinated between Brazilian, American, French and South African institutes. The new SA Agulhas II (Figure 4) provides the ideal platform to deploy and service the many moorings and undertake ship-based measurements (temperature, salinity, pH, CO2 etc) along the dedicated transects shown in Figure 3. The SAMOC-SA science team, made up of UCT and DEA researchers and students, is presently planning Phase 1 of the mooring deployments across the eastern sector of the South Atlantic in midOctober 2013. The recent establishment and endorsement of SAMOC-SA as well as the availability of the SA Agulhas II should mean that these
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Figure 4: The new SA Agulhas II: The ship was commissioned by the Department of Environmental Affairs (DEA) and built in Rauma, Finland by STX. Launched in April 2012, she is currently the most state-of-theart polar research vessel in the world. The SA Agulhas II will form the backbone of the SAMOC-SA programme providing the SAMOC-SA science team of UCT and DEA scientists and students with a platform to deploy and service the many moorings and measurements along the various transects shown in Figure 3. objectives can finally be achieved, placing South Africa in a more pivotal role within the international arena.
The Agulhas Current The Agulhas Current flows southwards along the east coast of Africa from 29°S to 34°S. It is a narrow current, fast flowing and strong. The current forms the western boundary of the southwest Indian Ocean.
Agulhas Retroflection The Agulhas Current retroflects – turns back on itself – in what is oceanographically termed a retroflection. The water from the retroflection forms the Agulhas Return Current, which then rejoins the Indian Ocean gyre. A gyre is any large system of rotating ocean currents – particularly those that are involved in large wind movements. The remaining water is transported into the South Atlantic gyre in the Agulhas leakage – through surface water filaments and Agulhas rings.
Agulhas Leakage A large amount of Indian Ocean water is leaked directly into the South Atlantic. The Indian Ocean water is significantly warmer and saltier than South Atlantic water, which means that the Agulhas leakage is a significant source of heat and salt for the South Atlantic gyre.
Agulhas Rings A model image showing sea surface temperatures south of Africa, The influence of the Agulhas Current along the east coast of South Africa is clearly visible. South of Cape Agulhas the current retroflects, or turns back on itself, into the Indian Ocean, forming the Agulhas Return Current. The leakage of warm Agulhas water into the South Atlantic is clearly shown. Image: GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany
between the upper and lower layers of the global ocean circulation (Figure 2). Because of this link, the overturning circulation within the Southern Ocean strongly influences climate patterns and the cycling of carbon and nutrients. As a consequence, any changes in the Southern Ocean will affect the rest of the world’s oceans. The observations that have been made so far suggest that the Southern Ocean is warming more rapidly than the global ocean average – salinity changes driven by shifts in precipitation and ice melt have been observed and the uptake of carbon dioxide has decreased. In response to these changes, Southern Ocean ecosystems are being forced to adapt or are becoming less diverse. Unfortunately, the lack of historical observations means that it will take time to understand this region. The scientific oceanographic community is in desperate need of an MOC monitoring array across the entire South Atlantic. Despite the South Atlantic’s climatic importance, there is no observational system in place to monitor the inter-ocean exchanges. Although individual efforts to measure the circulation across natural chokepoints such as the Drake Passage and south of Africa exist, none of these efforts have previously
been coordinated, nor have these systems been designed for longterm monitoring. This is where the South Atlantic MOC (SAMOC) comes. SAMOC-SA has been funded through the National Research Foundation’s, South African National Antarctic Programme (SANAP). How does South Africa fit into SAMOC? SAMOC is an integrated international observational oceanographic programme extending from south of Africa across the entire South Atlantic (Figure 3). The large meridional gap between the African and Antarctic continents provides a significant crossroad for water mass exchange between the subtropical Indian and Atlantic Oceans. Most of the Indian to Atlantic Ocean transfer takes place near the Agulhas Retroflection region through the generation of large warm rings – known as the Agulhas leakage. Observations have reported that a highly energetic field of anticyclonic and cyclonic eddies in the Cape Basin interact extensively with each other, resulting in the vigorous stirring of water mass properties and the transport of substantial anomalies of heat from the Indian into the Atlantic Ocean. Recent studies suggest that the Agulhas leakage is critical – through the shedding of Agulhas rings this
The Agulhas Current forms rings, which are anti-cyclonic cores of warm water that are lower in biologically productivity than cold water. This means that they carry water with a lower concentration of chlorophyll than the cooler waters of the South Atlantic –chlorophyll is the pigment that allows photosynthesis.
gateway is one of the major sources of salinity increase in the South Atlantic. Sediment records dating back 15 000 years prove that this leakage correlates to the strength of the North Atlantic MOC. In order to understand the nature of global climate change, the physical understanding and longterm monitoring of the inflow of Indian waters into the Atlantic Ocean is essential. The aim of SAMOC is to improve and deepen this knowledge. ❑ Dr Isabelle Ansorge is a senior lecturer in the Oceanography Department at the University of Cape Town. She is an observational oceanographer and spends many weeks at sea in the Southern Ocean. Her research interests are in the Subantarctic Belt and in particular the impact that changes in ocean circulation have on the ecosystem of the Prince Edward Islands. Dr Mike Roberts is an observational oceanographer and is employed at the Department of Environmental Affairs – Oceans and Coasts Division. Mike is one of South Africa’s leading experts in deep-sea oceanographic mooring deployments and has been involved in technical training with the Cape Peninsula Techikon (CPUT) since the early 90s. References Lumpkin, R and Speer, K. Global Ocean Meridional Overturning. Journal of Physical Oceanography, 2007;37, 2550–2562.
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Getting an ARGO float into the water – quick and easy! Image: SAEON
Robots in the ocean Why do we need a global ocean observing system? by Thomas Mtsonti and Isabelle Ansorge
I
n the past three decades, discussions of global warming have been restricted mainly to academic debates. Now, however, the same topics provide fuel for public debate and mounting pressure for increasing government action, as substantial indicators suggest that climate is undergoing significant variability and change. The flurry of new studies into the climate system have worrying conclusions. However, although the changes seen may be a response of the oceans to global warming, they could just as easily be a natural mode of oceanic variability. Recent reports have confirmed that sea level is rising at an accelerating rate of 3 mm/year, while August 2012 has seen the Arctic sea ice cover shrink to its lowest level ever. Extreme weather events such as droughts in Africa, intense hurricanes off Florida, unprecedented warm spells in the European winter, dust storms in the Sahara or raging bush fires in Australia are now seen regularly. In the past 10 years we have seen eight of the
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The ARGO float in the water.
Image: SAEON
warmest years recorded since 1860. An understanding of the changes in both the atmosphere and ocean is crucial in order to guide international action and policy. However, a lack of sustained earth observations has hindered the development and validation of the climate models that we need to accurately forecast these changes. In 1998 a plan was put forward to develop a global array of
profiling floats throughout the ice-free areas of the deep ocean. This array would, for the first time, provide a systematic robotic monitoring system of the global oceans. That initiative was ARGO. How does ARGO work? ARGO is a multi-national network of 3 000 profiling floats. ARGO floats are approximately 1.1 m tall and
Where does the name ARGO come from? The ARGO float programme was designed to operate on the same 10-day cycle as altimetry satellites Poseidon and Jason-1. These satellites are designed to monitor global ocean circulation, but they only measure what happens at the surface of the oceans. ARGO collects data in the upper 2 000 m of the ocean. ARGO is named after the ship in which Jason and the Argonauts set sail in search of the golden fleece, in ancient Greek mythology.
There are 3 623 floats currently in operation in the world’s oceans. Image: The ARGO Programme
A diagram showing the ARGO float cycle.
Image: The ARGO Programme
An example of ARGO in the South Indian Ocean. The green dots represent where the ARGO float came up to the surface every 10 days. Interesting to note is the speed at which the float travelled along the east coast of South Africa – over two knots an hour!
surface, collecting temperature and salinity measurements on the way up. At the surface, the float transmits its data and position via the ARGO satellite system before repeating another 10-day cycle. ARGO floats operate on a technique based on differential buoyancy in which an air bladder inflates or deflates, allowing the instrument to sink and rise again to the surface every 10 days. ARGO floats are designed to have a lifetime of three to four years or between 150 and 200 cycles. The observations will be used to make ‘weather maps’ of the ocean, to initialise climate forecast models for the ocean atmosphere system ▲ ▲
weigh around 40 kg. The casing is made of aluminium tubing and is strong enough to withstand pressures exceeding 2 000 m. The sensors are able to measure temperature, salinity and pressure. An antenna transmits data from the surface via satellite to more than 60 ground stations and from there, the data goes through a series of quality checks before becoming freely available to the public. When deployed at the surface, each float sinks to a parking depth of 1 000 m where it drifts for approximately nine days. Before surfacing the float sinks to 2 000 m. On day 10 the float rises to the
The nuts and bolts of the ARGO system.
Image: The ARGO Programme
Temperature and salinity profiles for the top 2 000 m. This is the data collected during the ascent of the ARGO float to the surface. Image: The ARGO Programme
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Teaching ARGO in South Africa The launch of the first ever African ARGO programme took place in December 2009, when the first South African floats were procured and launched by SAEON (South African Environmental Observation Network) through SANAP. In the past, the SA Agulhas has provided a platform to seed over 200 ARGO floats on behalf of the UK Met and Argo offices in the Southern Ocean – but the acquisition of two ARGO floats by SAEON was a first. Scientists from SAEON and the University of Cape Town deployed the two floats while sailing to SANAE (South African National Antarctic base) at 41˚S (within a large ocean eddy) and at 60˚S. Young researchers on board the SA Agulhas were trained in the techniques of deployment. Dr Sebastiaan Swart is one of the South African scientists who uses ARGO data in his research. Dr Swart’s focus is on the Southern Ocean heat and salt fluxes in a remote area, about which little is currently known. Hopefully ARGO will fill some of the gaps.
An example of all the data points for one year south of Africa.
Image: The ARGO Programme
The advantages and limitations of the ARGO system Advantages Limitations Floats are relatively easy to deploy Due to the nature and length of time spent at the parking depth datasets contain 9-day gaps New designs include oxygen, bio-optic sensors
Float trajectories are relatively coarse resolution with a GPS position for the float only recorded every 9 - 10 days.
Improve ocean model and forecasting capabilities
No control of where they go in the oceans
All the data is incorporated into World Data is only collected on the profiling cast Ocean Database 2009 and Levitus 2012 They are cheap compared to the cost of a research ship
Southern and Arctic Oceans still a problem for floats due to winter sea ice formation
Quite cumbersome to carry and transport – They are truly robots in the ocean the technical team need to decrease size and weight of the floats Very difficult and expensive to retrieve floats They can conduct extended missions in the ocean and so the majority sink to and over 150 10 day cycles the bottom once their lifetime is reached (after approximately four years) Staff and teachers learning about ARGO. Image: The ARGO Programme
They acquire and communicate data to researchers throughout the world without the direct involvement of ships or people
Once deployed, any problems with sensors cannot be easily fixed
Data is freely available and easy to download
Shelf seas and coastal regions where the depth is <1 000 m are currently not being monitored by ARGO due to the parking depth
and to improve our understanding of the ocean itself. With the array now complete over 100 000 profiles are received each year.
Students learn about ARGO data in real time. Image: The ARGO Programme
Teachers and school children from six previously disadvantaged community coastal schools are starting to follow these two ARGO floats as they monitor the track of both floats through the Southern Ocean in a bid to engage and stimulate a new generation of marine scientists. The students are able to download the data from a website and monitor the behaviour of the ocean from their school. Working with the online records as well as interpreting the ocean profile plots and drawing up conclusions from the dataset will undoubtedly boost their skills in science-related activities. Allowing students to access data not only helps them to become comfortable using computers but also provides skill in data analysis and interpretation. The fact that the ARGO programme is in real time makes this exercise so much more interesting and hands-on.
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Problems with ice – what happens? One of the major problems with research south of Africa is the lack of access and so observations in the Southern Ocean are sparse, especially in winter. The Southern Ocean is remote, the environment is hostile and the vast extent of seasonally varying sea ice means that implementing a year-round observational system is challenging. As a consequence the Southern Ocean remains undersampled when compared with other ocean regions. The current ARGO float array is not equipped to work in the ice. Sensors and the antennae are fragile and easily crushed by sea ice. A new design of ‘ice float’ is
currently being tested. The ice floats are standard ARGO floats that have undergone substantial modifications to their temperature sensors. These floats are programmed to check for the presence of sea ice above them using a sea ice detection algorithm. If ice is detected, the data that the float has collected is stored for up to six months. An ice float can determine if there is ice above by calculating the mean water temperature between 20 and 50 m. If the mean temperature is below -1.78 ˚C the float assumes that there is ice in the surface layers and sinks back down to its parking depth. The inclusion of this ice-detecting algorithm increased the survival probability of all floats deployed in the polar regions by over 200%. Who pays for ARGO? ARGO is sponsored by two international programmes: the
World Climate Research Programme’s CLIVAR, which seeks to understand CLImate VARiability and predictability from years to decades. The second sponsor, GODAE (Global Ocean Data Assimilation Experiment) demonstrates the value of real-time operational ocean prediction. The core aim of GODAE is to provide improved ocean observations and forecasts for the scientific and technical community. Each ARGO float costs about $15 000. The array has on average 3 000 floats, but to maintain this number at least 800 floats need to be deployed each year. The total annual cost of ARGO is about $20 million or roughly $25 000 per float-lifetime, which means that each profile costs around $200 or R1 800. The best news is that the data is absolutely free. Who is involved in ARGO? Many new countries have joined the original 10 countries who launched floats in 2000. At the latest count 27 countries have deployed or assisted with float deployments.
What does the future hold for ARGO? ARGO is still a young project but its main drive is to reach a permanent global array of 3 000 floats – this will provide over one million ocean profiles over the next 10 years. Although ARGO’s first priority was to complete a basic temperature/ salinity array, new sensors such as dissolved oxygen, bio-optic, nutrients, and chlorophyll sensors are necessary to broaden the scientific community base of this programme. ARGO is also limited by the present ARGO communication system, which restricts the size of data (only 100 depths per profile) per transmission. To ensure reliable data transmission each float must spend several hours at the surface. New communication technologies using iridium coupled with improved GPS navigation promise to remove these restrictions. Sustainable funding and deployment opportunities are another challenge. ❑
Dr Isabelle Ansorge is a senior lecturer in the Oceanography Department at the University of Cape Town. She is an observational oceanographer and spends many weeks at sea in the Southern Ocean. Her research interests are in the Subantarctic Belt and in particular the impact that changes in ocean circulation have on the ecosystem of the Prince Edward Islands. Thomas Mtsonti networks with key oceanographic and climate scientists in order to facilitate the integration of marine sciences into school sciences. He has a BSc (Education) from the University of the Western Cape and has worked with people from all sectors of our community. His experience includes teaching high school science and later establishing and managing schools’ outreach programmes.
Where can I find ARGO data? Argo portal: http://www.argo.net General information: http://www.argo.ucsd.edu Coriolis Global Data Centre: http://www.coriolis.eu.org/cdc/argo_rfc.htm US Global Data Centre: http://www.usgodae.org/argo/argo.html
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An ocean of eddies.
Image: National Science Foundation
A swirly world ... measuring ocean currents from the new SA Agulhas II Understanding ocean currents is essential to understanding the ocean itself – the physical and the living components. By Tammy Morris, Isabelle Ansorge and Patrick Vianello.
T
his breathtaking image shows a perspective you may not have seen before: you are looking at the South Pole, and seeing the bottom edges of South America, Africa, and Australia. The red band encircling Antarctica is aptly named the Antarctic Circumpolar Current. This mighty current is the only ocean current that completely encircles the globe. Colours show current speed, with blue for slowmoving water and dark red indicating speeds above 1.5 km per hour. The pale blue halo around Antarctica shows sea ice, which in winter grows to cover an area equal to the size of the Antarctic continent.
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Physical oceanography Physical oceanography is a fascinating earth science discipline that aims to unravel the mysteries of how the physical parameters of the ocean behave – temperature changes over space and time, the saltiness of the ocean, how waves (both small waves and the larger more devastating tsunamis) affect coastlines, and of course where all the water comes from and where it goes. Understanding ocean currents and their dynamics is key to improving our knowledge of the pathways of ocean flow. A simplified illustration of current dynamics was shown in the movie Finding Nemo, where the gregarious sea turtles hop on and off the East Australian
Current or rather ‘the E-A-C dude’ to get around. Many biological organisms take advantage of ocean currents to aid them in their migrations to and from feeding grounds and spawning areas. Ocean currents are not only important for the transport of marine organisms, but they also influence climate change, local climate and weather patterns and the exchange of heat and salt around the globe using what marine scientists call the ‘conveyor belt’ (Figure 1). Our ocean currents South Africa is unique in that it is bordered by three oceans – acting as a gateway to the point at which three oceans meet. The energetic Agulhas
Q Physical oceanography
Figure 1: A diagram showing the global conveyor belt of the world’s ocean pathways. Throughout the Atlantic Ocean, the circulation carries warm waters (red arrows) northward near the surface and cold deep waters (blue arrows) southward. Image: NASA/JPL-Caltech
Figure 3: An example of two acoustic Doppler current profilers that are used to measure ocean currents from a ship. These instruments are mounted to the hull of the ship and can collect data (ocean currents – speed and direction) as the ship is underway. Image: Isabelle Ansorge
Measuring ocean currents How do we measure these ocean currents? In years gone by, surface currents were recorded and plotted using ships’ drift measurements. These observations are charted back to the early days of merchant and naval maritime navigation and in many instances hold true to current knowledge. However, deeper currents remained a mystery for a very long time. A number of experiments, including temperature measurements as a tracer for deep current flow, became the rudimentary beginnings of the ‘global conveyor belt’ theory (Figure 1). The Swallow float, named after the English oceanographer John C Swallow (1923 1994) was a simple device made from neutrally buoyant aluminium, which was deployed at a particular depth and followed using sounders from the vessel at 10 Hz. The return signal received on the hydrophones deployed over the side of the vessel helped to triangulate where the float was in relation to the vessel, and from subsequent measurements the speed and direction of the current could be determined.
Figure 2a and b: Diagrams showing the fronts and currents of the Benguela Current in the south-east Atlantic and the Agulhas Current in the Indian Ocean. Ocean currents such as the Benguela and Agulhas Current and associated Agulhas rings are shown by solid arrows. The bathymetry is shown as blue lines in contours of 1 000 m. The Agulhas Current with its warm subtropical water (red) sheds Agulhas rings at the Agulhas retroflection, which then move north-westwards into the South Atlantic Ocean. They are interspersed by cold clockwise eddies. The wind-driven upwelling along the west coast is shown. South Africa is also a gateway to the Southern Ocean which lies south of the Subtropical Convergence (dashed blue line).
In the last 20 - 30 years, measurement techniques have undergone a quantum leap in sophistication. First, a rotor type current meter deployed at a particular depth was developed – but this provided only single point measurements and was spatially limiting. Following on from this an advanced acoustic measurement-based instrument, using the Doppler shift technique, was designed and high resolution current velocity and direction could finally be accurately and effectively mapped in the top 500 m. This instrument is called an acoustic Doppler current profiler (ADCP) (Figure 3). ▲ ▲
Current, a western boundary ocean current lies off the east coast of South Africa and transports warm, salty water from the subtropical southern Mozambique Channel southwards. South of Africa the current turns back on itself, or retroflects, and recirculates along a curvaceous trajectory eastwards as the Agulhas Return Current. On the west coast of South Africa the colder, more sluggish, Benguela Current carries cold water from the south Atlantic up along the west coast and into Namibian waters. This current is rich in nutrients and highly productive, giving rise to South Africa’s fisheries. The Southern Ocean is host to the eastward flowing Antarctic Circumpolar Current which, as its name suggests, circulates from west to east around the continent of Antarctica. This current is made up of numerous fronts – areas of interaction between warmer and colder water masses – which are known to be rich in productivity and biodiversity. Figures 2a and b show a broad overview of these currents and how they tend to interact with one another.
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Figure 4: A diagram showing how pulses sent from an ADCP travel back and forth through the upper ocean measuring ocean current speed and direction.
Figure 6: ADCP data for 50 m showing the anti-clockwise direction of an Agulhas ring crossed by the SA Agulhas II in July 2012. The Agulhas ring showed velocities exceeding 1.5 metres per second!
How does an ADCP work? Sound waves are transmitted through the water column from a transducer head, which is mounted on the underside of any research vessel. These sound waves are reflected back towards the transducer after ‘bouncing’ off particles within the water column (Figure 4). A lower return frequency indicates that particles are moving away from the vessel, while a higher frequency indicates that particles are moving towards the vessel, thus providing current direction. This return frequency is then analysed extensively to determine the exact trajectory and speed of the current, and also at which depth the return signal was received. Depending on the initial frequency of the sound wave transmitted through the water column, the ADCP will determine the depth that the sound wave is capable of penetrating and thus just how deeply the currents extend through the water
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Figure 5: Temperature and velocity snapshot (5-day average centred at 15-JUN-2006) from a high-resolution nested model, INALT01, developed by Jonathan Durgadoo, a former UCT Oceanography student now studying for a PhD at GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany. The figure shows the movement and pathway of large, anticlockwise Agulhas rings carrying subtropical Indian Ocean water into the South Atlantic.
column. Onboard the SA Agulhas II, with a 75 kHz Teledyne RD Instruments Ocean Surveyor installed, depths of up to 700 m are possible. This is considerably deeper and certainly more accurate than either drift experiments or Swallow floats deployed over 50 years ago. During the maiden scientific voyage onboard the SA Agulhas II, a number of interesting features were crossed while steaming southwards towards the ice edge. One of these was a large anti-cyclonic eddy that had been spawned from the Agulhas Current at the retroflection (Figure 2) – known oceanographically as an Agulhas ring. These perturbations are formed at the Agulhas retroflection and travel northwestwards across the Atlantic Ocean (Figure 5). Anti-cyclonic eddies circulate in an anti-clockwise direction in the Southern Hemisphere and have at their centre a warm body of water. Figure 6 shows a horizontal plot of velocity vectors at 50 m as the SA Agulhas II travelled from north to south through this feature. The transect shows, in the north, strong westerly currents, which gradually veer southwards as the centre of the ring is reached and the currents become almost nonexistent. As the vessel crosses through this Agulhas ring southwards and away from the centre, the currents increase in strength while shifting their flow back towards the east. This shows an anti-clockwise rotation in the current flow, as indicated by the guiding circle and black arrows superimposed over the ring. In Figure 7, the magnitude (speed) and direction of the currents are plotted as vertical sections to show the anticyclonic nature of the Agulhas ring in the top 500 m surface layers. The data was plotted as the SA Agulhas II steamed from north to south (x-axis) with depth plotted against the y-axis. The plots highlight the same anti-
clockwise currents observed in Figure 6, but over a depth of 500 m. Strong currents (1.2 m/s) are noticeable north of 35˚S, gradually weakening (0.3 m/s) as the middle of the ring is encountered and strengthening again towards the southern end of the transect. The vertical section plot of direction shows categorically the anti-cyclonic ring with westward flow right through the water column to the north and eastward flow to the south of the ring, with a directional change through 180 degrees (south) in the middle of the transect. What this data suggests is that the ring surveyed on this scientific inaugural voyage of the SA Agulhas II had a strong surface signature but that this weakened with depth, indicating that this ring is beginning to lose its strength and will eventual dissipate into the surrounding waters. How do we work this out? Satellite technology has become increasingly sophisticated over time and sensors have been developed that calculate the sea surface height anomalies of the ocean surface – basically the hills and valleys of these mesoscale eddies, Agulhas rings and other turbulent features form on the sea surface. These are not visible to the naked eye, but can be determined remotely by satellites. The energetic variability in the Southern Ocean can thus be monitored weekly to track where interesting features, such as mid-ocean eddies and Agulhas rings originally come from and where they go. Such a study was carried out on the same transect in 2008, when an anticyclonic ring was surveyed (Figure 8) and its lifetime monitored. Scientists were able to show that the ring was formed at the Agulhas retroflection and remained in the area for over five months, before moving westwards into the South Atlantic. Figure 9 shows the route taken by an Agulhas ring from its point of origin
Figure 7: Highlighting the speed and direction of an Agulhas ring in the top 500 m as it is crossed by the SA Agulhas II on her way to 59˚S.
Figure 8: Oceanographic section (temperature and salinity) across an Agulhas ring collected from the ship-based CTD. The upper panel shows temperature and salinity all the way to the sea floor while the lower panel shows the same data but zoomed into the top 1 000 m and over the Agulhas ring region. Grey lines in the upper panel demarcate the latitudinal width associated with the lower panel. What is very clear is the presence of a warm (>14 ˚C) and salty (35.2) water just south of 43˚S – typical of an Agulhas ring that has moved southwards from the Agulhas retroflection. Sea floor is shown in the upper panel in white while white blocks in the lower panel identify gaps in the data.
(Agulhas retroflection region) in May 2007 to when the ring was crossed during the cruise 10 months later. It seems that the Agulhas ring could be tracked by satellite up until September 2008 when its surface signal weakened – suggesting that the feature lasted for over 17 months. Ocean currents and mesoscale features such as Agulhas rings are a wonderful vehicle for transporting heat, salt and biota between the Indian and Atlantic ocean basins. The oceans south of Africa can certainly be described as a swirling mass of heat and salt – physical oceanography at its most energetic. ❑ To find out more about an ADCP: http://www.whoi. edu/main/ships-technology
Figure 9: Satellite data showing snapshots of sea surface anomalies such as Agulhas rings and mid ocean eddies. These anomalies represent either cold core, cyclonic eddies (blue) or warm, anti-cyclonic eddies (red). An Agulhas ring was formed in May 2007 and followed over a 17-month period. The white dot represents the core of the ring as it moves southwestwards into the South Atlantic. The black line denotes the trajectory taken by the ring during its 17 month journey. Overlaid onto these satellite maps is the cruise track occupied in March 2008.
Tammy Morris is Projects and Research Coordinator for the Operational Oceanography section of Bayworld Centre for Research and Education (BCRE) based in Cape Town. She has completed her Master’s of Technology at Cape Peninsula University of Technology and is working towards a PhD in Oceanography. Her main areas of interest are mesoscale eddy dynamics in the Mozambique Channel, but she has worked on numerous oceanographic projects all around the South African coast and up into East Africa looking at physical oceanography and the instrumentation used, along with capacity building initiatives to train young scientists and technicians developing their skill in the field. Isabelle Ansorge is a senior lecturer in the Oceanography Department at the University of Cape Town. She is an observational oceanographer and spends many weeks at sea in the Southern Ocean. Her research interests are in the Subantarctic Belt and in particular the impact that changes in ocean circulation have on the ecosystem of the Prince Edward Islands. Patrick Vianello is a UCT PhD student studying the ocean circulation in the Indian Ocean. His Masters degree (graduated in 2010) focused on the pathway of Agulhas rings into the South Atlantic Ocean. The results from this MSc study are shown in Figures 8 and 9.
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Gliders in the ocean Africa’s first ocean gliders navigate the turbulent and remote Antarctic waters. By Seb Swart.
The path that the SA Agulhas II cut through sea ice near Antarctica during December 2012.
Image: CSIR
The CSIR’s Dr Seb Swart (in front) and the marine engineers from Sea Technology Services’ Derek Needham (left) and Andre Hoek, with one of Africa’s first long-range ocean gliders. Relatively inexpensive platforms compared to ships, these gliders sample the upper 1 000 m of the ocean for periods of up to six months. They relay data ashore within hours of collection and can be controlled globally via the satellite to Internet relays. Image: CSIR
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I
t has been a remarkable start to the newly launched glider programme in South Africa. Right now, five state-of-the-art, autonomous ocean gliders – a first for Africa – are navigating their way in the remote Southern Ocean thousands of miles south of South Africa. As they move through the depths the gliders are collecting data to 1 000 m below the surface and sending it back to climate scientists and oceanographers in real time. The gliders represent one of the most novel technologies available to oceanographers and marine biologists today. Funded by the Department of Science and Technology (DST), the gliders form part of a larger programme – the Southern Ocean Carbon and Climate Observatory (SOCCO) – to build South Africa’s capacity in providing high-quality, precise data and research related to carbon-climate interactions in the Southern Ocean. In addition, the gliders spur innovation in engineering research and scientific sensor development within the marine research community.
A diagram showing an example of a glider sampling path
A glider is deployed from the stern of the SA Agulhas II in December 2012 on the way to Antarctica. Image: Dave Scott
The sensor configuration of South Africa’s gliders includes a conductivity-temperature sail to measure salinity and temperature, a dissolved oxygen and light (PAR) sensor. A chlorophyll sensor sits below the glider (not indicated). An antenna at the back of the glider is used to communicate with satellites to get GPS locations and send data to researchers on land. Image: CSIR
Researchers and technicians were trained to operate and pilot gliders by US engineers in Cape Town. Image: iRobot
sawtooth-like profile between the surface and 1 000 m depth, providing data on temporal and spatial scales unavailable to other sampling platforms. In order to navigate properly and make adjustments to heading and dive behaviour, the glider makes surface GPS fixes, and recieves pressure sensor, tilt sensor, and magnetic compass information. Vehicle pitch is controlled by movable internal battery packs and steering is accomplished by tilting the battery packs to control roll. A standard dive from the surface to 1 000 m and back to the surface again takes approximately five hours to complete. As soon as the glider
Seaglider ‘Brain’ is carefully deployed into the sharky waters of False Bay for pilot training – the first glider deployed into African waters. Image: Sarah Nicolson
surfaces it ‘calls’ researchers back in the laboratory via iridium satellites and downloads all its valuable data. Glider pilots are also able to send commands to the glider in order to change a huge range of parameters, such as way points, sensor sampling rates and dive speeds. The South African gliders are fitted with a relatively heavy load of
▲ ▲
How they work The underwater glider uses small changes in its buoyancy in conjunction with wings to convert vertical movements to horizontal motion and so propel itself forward with very low power consumption. The gliders use buoyancy-based propulsion by moving oil in and out of an external bladder and have no moving parts (like a propeller or rudder). This means that they can cover a significant range over a long period of time without using much energy. This extends ocean sampling missions to times of many months and to ranges of thousands of kilometers. Gliders follow an up-and-down,
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Left: A map showing the deployment locations of SOCCO’s gliders in the remote Southern Ocean as part of Southern Ocean Seasonal Cycle Experiment (SOSCEx)
A conductivity-temperature-depth carousel is deployed through the moon-pool of the ship to collect additional data, capture water samples and to calibrate the sensors on the gliders. Image: Dave Scott
instruments – four sensor packs that collect data about the temperature, salinity, dissolved oxygen, light and chlorophyll in the water. South Africa’s Seagliders are the first in the world to be fitted and tested with light sensors that measure the amount of sunlight that is available to microscopic plant cells – phytoplankton – that use light to photosynthesise and grow.
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The road to deployment It all began in September 2011, when the first two Seagliders, made by iRobot Corporation in the USA, arrived in South Africa – the first of their kind on the continent. Affectionately christened Brain and Vader, the two bright yellow gliders were immediately put to test and placed in the sharky waters of False Bay near Cape Town with the help of the Institute of Maritime Technology’s resources. After five days of packed lectures and sleepless nights, while continually monitoring the glider’s movements and health, 11 South African researchers, engineers and technicians from six different institutes (CSIR, UCT, DEA, DAFF, IMT, BCRE) were officially awarded glider pilot status, meaning that they could independently navigate and understand gliders in the ocean. The first long-range and longduration mission began in February 2012, when ‘Brain’ was deployed offshore St Helena Bay in the Southern Benguela Upwelling Region of South Africa. For 32 days the lonesome glider managed to accurately follow a predetermined sampling grid that covered an area of approximately 10 000 km2. The data is already helping oceanographers to understand how the Benguela region works in terms of coastal upwelling and the impacts the ocean has on the dynamics of local ecosystems, where species such as the West Coast Rock Lobster thrive. Glider missions don’t always go as smoothly as planned. At the end of
this particular West Coast deployment it became obvious that the glider was having trouble contacting us via the satellite to tell us how it was doing and where it was. This led to an emergency recovery of the glider – a navy boat was scrambled and deployed in the Benguela within four hours. By the end of the same day the glider was fortunately found by engineer Andre Hoek, floating near its last GPS location. After the hours of panic and recovering the glider safely, we discovered that the CSIR digital phone line software patches had been updated and this interfered with the phone calls coming in from the glider. Our final glider mission, before taking on the Southern Ocean, took place on the new South African polar ship – the SA Agulhas II. In June 2012, for 47 days, CSIR deployed one of the gliders from the stern of the 130 m vessel a few kilometers off the coast of Hout Bay, Cape Town. The glider was used to sample the dynamic region of the shelf break and what is known as the Good Hope Jet, a sharp, narrow current, which has previously been poorly studied. The new glider data should give researchers information about the jet’s dynamics, variability and strength, which are known to play a crucial role in transporting commercial fish larvae between the east and west coasts of South Africa. Their destiny lies in the Antarctic seas The gliders’ true purpose was always to complete gruelling missions in the frigid, remote and challenging Southern Ocean. The deployments form a crucial part of SOCCO’s Southern Ocean Seasonal Cycle Experiment (SOSCEx) from austral spring 2012 to autumn 2013, which combines measurements taken from ships, gliders and floats. The experiment includes participation by international partners from the United States, Norway and France. The research work aims to improve the global understanding of the link between the carbon cycle and climate in the Southern Ocean. The vast Southern Ocean is one of the most important carbon-climate systems on Earth, with recent estimates suggesting that 40% of all CO2 emitted is stored in the Southern Ocean. On 20 September 2012, in persistent
Engineering student interns, Ashley Botha, Sinekhaya Bilana and Jean-Pierre Smit assess a Rutgers University Slocum glider in the newly launched Southern Ocean Engineering, Research and Development Centre. Image: CSIR
Ice bergs and sea ice are a constant hazard that need to be avoided when working in the Southern Ocean. Image: Dave Scott
Salinity data from the surface to 1 000 m from one of the gliders in the Southern Ocean.
winter conditions and an 8 m swell near Gough Island, the first two glider deployments from the SA Agulhas II marked the start of SOSCEx. They were deployed into the heart of the world’s largest ocean current, the Antarctic Circumpolar Current – the first time that gliders were deployed into this region of the Southern Ocean – currently the most under-sampled ocean in the world. Two months later, during the annual South African voyage to Antarctica, another three gliders were deployed two thousand kilometers downstream from the first two in order to continue the duration of the experiment. Back home, glider pilots were left with the arduous task of navigating five gliders through the turbid Southern Ocean, where strong ocean currents and eddies make the gliders steer off course. Fortunately, the extensive sea trials done in South African waters had adequately prepared the glider pilots for the long hours and precise navigating skills required to see the experiment through the entire Antarctic summer. Until now, the five gliders have
managed to dive to 1 000 m depth and back to the surface again over 2 200 times, while travelling a total horizontal distance of 6 000 km – equivalent to the distance between Cape Town and Rio de Janeiro, Brazil. They have been collecting exceptionally goodquality data at unprecedented spatial and temporal scales. For the first time, researchers will be able to understand the role the upper ocean plays in the behaviour, health and distribution of phytoplankton over their whole summer growing season. Understanding what makes these phytoplankton tick is crucial since they form the basis of the food chain and take up vast amounts of CO2 from the atmosphere during photosynthesis. Previously, oceanographers have been reliant on ships to collect most of their data. Using a ship is extremely expensive – just one day on the SA Agulhas II costs R300 000 in fuel and the crew’s salaries. With robots, like gliders, researchers can collect data for many months at a time without having to use the ship continually – saving a lot of money. The gliders are also helping
to feed South Africa’s need for marine engineers and technicians. Late in 2012 a new facility opened in Cape Town – the Southern Ocean Engineering, Research and Development Centre, which was formed to maintain ocean-going platforms, such as diving and surfacewave gliders, and to stimulate new developments and improvements around ocean instrumentation and sensors. In January 2013, three new mechanical and electrical engineering students began their internship at the facility. They will be exposed to world-class experts in the field of marine technology and operational support and add to the pool of seagoing engineering staff. It is clear that robotic gliders are poised to play an important role in unlocking the many secrets of the ocean and the impact it has on our climate. In doing so, they also provide a platform for the next generation of students and researchers to be inspired by and educated about marine and climate sciences. The continued experience researchers and engineers gain using autonomous platforms will help place South African marine research firmly in the international spotlight for years to come. The path of all the gliders can be followed using this link: http://access. oceansafrica.org. ❑ Dr Seb Swart is a senior researcher at the Ocean Systems and Climate group within CSIR. He is an observational oceanographer and spends time at sea in the Southern Ocean deploying instruments and collecting water samples for analysis in the lab. His current focus is leading the newly established glider facility in South Africa. His core research activities involve understanding the dynamics of the upper ocean and its impact on climate and ecosystems.
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A photo of a benthic worm in a petri dish. These benthic worms are also planktonic organisms and feed off fish larvae. Image: Gerda du Plessis
Some members of the plankton are extremely small. Gerda du Plessis introduces microbial oceanography: an introduction to microscopic plankton.
Microbes in the ocean What is microbial oceanography? Microbial oceanography is the study of the ocean’s microscopic organisms and their environment. This subdiscipline was formed when the subjects oceanography, marine biology and microbiology were merged. It was only during the last 20 years that bacteria were counted during surveys of marine life during oceanographic
The distribution of sizes over the range of plankton species.
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voyages. Microbial oceanography then became part of research voyages and scientists could keep track of population sizes and dynamics. Initial classification was done mainly by grouping organisms into size classes. The smallest fraction was reserved for viruses, also known as femtophytoplankton (<0.2 µm), and bacterio-/or picoplankton (0.2 - 3 µm). The larger nano- to megaplankton, including organisms as big as the common bluebottle or ‘Portuguese man of war’, have been extensively studied throughout the world’s oceans. With the advent of new molecular techniques and DNA fingerprinting technologies, the classification and identification of bacterial communities became easier to track and compare. A large movement in biogeographical science focused on the distribution and evolution of geographically divided communities. Two pioneering studies, which took place in 2004 and 2007, include the global ocean sampling (GOS) expedition aboard the
Sorcerer II and Craig Venter’s DNA sequencing project of the Sargasso sea. Both laid the foundation for further biodiversity studies. Tracking biogeographical patterns and how they change with time and climate variability forms the base of microbial oceanography. The Global Ocean Sampling expedition is a dedicated scientific project that aims to sample and assess the genetic diversity of the world’s oceans. It was launched in 1998 by the Craig Venter Institute and has covered several important sailing routes.
Where do we find microorganisms in the ocean? Microorganisms can be found everywhere, from the photic zone down to the deepest trench. The photic zone is the first 100 - 200 m where sunlight penetrates the water column, allowing photosynthesis to occur.
Archaea The archaea are single-celled microorganisms that have no cell nucleus or other organelles with membranes within their cells. They are found in many different habitats and may contribute up to 20% of the Earth’s biomass. The first archaea that were discovered were called ‘extremophiles’ because they were found in extreme environments such as volcanic hot springs in temperatures above 100 °C. They are also commonly found in very cold habitats and very acidic or alkaline water. But there are also archaea that live in mild conditions.
One of the many filtration setups that can be used to filter seawater for analysis. Image: Gerda du Plessis
Archaea were first found in volcanic hot springs, such as this. Image: Wikimedia Commons
A typical consortium of bacterial colonies isolated from seawater on a nutrient agar petri dish. Image: Gerda du Plessis
particles of organic matter that are called ‘marine snow’. These particles are made up of detritus from dead plankton, zooplankton fecal pellets and other planktonic cells, which attach to form snow flake-like structures. Marine snow is mainly formed in the photic zone and sinks as it clumps together. This is also known to be the main mechanism by which carbon is transported to the seafloor. Bacterial colonies on these aggregates can reach anything between 108 – 109 cells/ml which is 102 – 103 more than the rest of the water column. Single celled cyanobacteria are also found in the photic zone.
Image: Wikimedia commons
Heterotrophic organisms live off reduced carbon and nitrogen. They cannot manufacture their own food
Heterotrophic bacteria are found throughout the various stratified depths, including the seabed where they colonise the sediment. One class of bacteria, called the SAR11 clade, has been found only in seawater samples and was originally discovered by using DNA-based methods. Similar methods have identified bacterial colonies in and on invertebrates of all sizes, including bryozoans, sponges and sharks. In some cases the microorganisms ▲ ▲
In 1998 William Whitman and his colleagues were among the first scientists to estimate the density of microorganisms in the sea, including the entire water column and the top 10 cm of sediment. This study concluded that the entire ocean contains roughly 1028 – 1029 bacteria and archaea, with an additional 1030 viruses. These communities aren’t evenly distributed in the water column. Their distribution is determined by nutrient supply. There exists a growing body of evidence that shows that their distribution is dependent on the distribution of nutrients and particulate organic matter. Bacteria colonise the
A species of cyanobacterium under the microscope.
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Bryozoans Bryozoans are aquatic marine invertebrates, also called moss animals. They are often found in colonies. Their main characteristic is a crown of tentacles lined with cilia. The organism feeds by sieving food particles out of the water through these tentacles.
A marine bryozoan colony.
Image: Wikimedia Commons
produce favourable compounds that help the animal/plant defend itself or even break down food otherwise hard to digest. Our knowledge of the oceans increases with every study and many possible sites of bacterial colonisation have yet to be explored. The Southern Ocean: a vast unknown bacterial resource The Southern Ocean links the two limbs of the overturning circulation that replenishes the Indian, Atlantic and Pacific sectors of the world’s oceans. Its uninterrupted Antarctic circumpolar current (ACC) shuttles and distributes water throughout the various oceans. The upwelling cold, nutrient- and oxygen-rich waters support a vast array of phytoplankton species, which in turn form the main food source for higher order predators. The Southern Ocean’s importance in the world food chain is therefore substantial and any modifications to its composition, whether they are seasonal or as a result of climate change, influence food chains worldwide. One example is the way that the surface waters close to the Antarctic continental shelf have become fresher – that is, less saline. This freshening has altered phytoplankton productivity, increasing bloom intensity to the south and decreasing further north. Changes such as these carry through
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(pumped into our coastal areas) has on the microbiome. Some believe that the vast tons of degraded biological effluent will cause eutrophication. The reason for this is the high nutrient levels (accompanying the biological waste) which enhance bacterial growth resulting in the extraction of large quantities of oxygen from the seawater. Above and beyond the negative impacts, we know that several new anti-cancer and antibiotic drugs have been isolated from marine microorganisms. One such example is the anti-cancer drug, Salinosporamide A, produced by the marine bacterium Salinispora tropica. It entered preclinical trials in 2006 to be used in cases of multiple melanoma. Rhodes University has generated several bioactive compounds from marine spnges, which are believed to be bacterial symbionts.
the predatory species, causing changes in feeding grounds and, in this case, penguin feeding behaviour. As yet it is impossible to predict what may happen if this freshening continues, but a hypothetical situation could be that feeding grounds change to such an extent that penguins need to swim further and stay out later to find the same amount of food. This will decrease the species’ breeding success and so their numbers. By studying changes in phytoplankton and zooplankton composition we can predict possible effects on the food chain long before they affect higher organisms. Why are microorganisms important? Marine microorganisms play an important role in the global carbon cycle. As part of the larger ecosystem, heterotrophic bacteria turn 99% of the primary carbon production back into minerals. The remaining 1% is then removed from the surface waters as marine snow, which settles to the sea floor. Studies show that the oceans have absorbed up to half of the CO2 production over the past 200 years, of which the excess (not removed by bacterial processes) is believed to have caused the global decline in ocean pH from 8.21 to 8.1. Another negative impact we have yet to fully consider is the effect that biological waste
How do biotechnologists study bacterial communities? The study of bacterial communities employs techniques from various disciplines. If the aim is to simply see what is there, we need to determine the level of research. Do we want a community ‘fingerprint’ that will merely show us a fraction of the picture? Do we want to know the species, genus, family and do we want to know the exact numbers of each genus? We can separate communities based on their DNA, total protein or lipid content. The best method, however, is to use a DNA fragment called the 16S rRNA gene. This gene encodes the small subunit of the prokaryotic ribosomal ribonucleic acid (RNA), which forms part of a complex that translates the messenger RNA template. This fragment works like a clock – it has several domains which mutate (change) at different rates and some that do not change over time (conserved regions). This allows us to estimate how two species may be different, because the fragment has changed to such an extent that the two organisms are less than 97% similar. Unfortunately culturing microbes has certain limitations, forcing scientists to look for different ways to study them. A new branch of science called metagenomics has made this possible by looking at community DNA, rather than trying to culture
The Antarctic circumpolar current The Antarctic circumpolar current is the largest current in the world and transports water clockwise from west to east around Antarctica. The current flows around the poles because there is no landmass connecting with Antarctica. This current keeps warm water away from Antarctica, which allows the continent to maintain its huge ice sheet.
Studying microbial oceanography: which subjects do I need and where can I apply? There’s no university in South Africa that offers a pure microbial oceanography major. However, at postgraduate level it is often easier to jump between disciplines. The University of Cape Town (UCT) offers undergraduate courses in oceanography as a major, which, when combined with physics courses allow you to go into a more physics-orientated study of ocean and atmosphere models. Physics and mathematics are a necessity in this line of work and are also advisable for a bachelors degree in microbiology or biotechnology. A degree in the latter is available at almost all South African universities, including University of the Western Cape, UCT and Stellenbosch University in the Western Cape. Metagenomics is a specialised field and can be studied at the Institute for Microbial Biotechnology and Metagenomics (IMBM) situated at the new Life Science building at UWC.
Antarctica and thus identifying spots of high diversity for gene ‘mining’. This also opens up a new avenue for monitoring these communities over the next few decades to identify the impact of global warming on our oceans, especially one as important as the Southern Ocean. ❑
The Antarctic circumpolar current (ACC) is the strongest current system in the world oceans, linking the Atlantic, Indian and Pacific basins. Image: Wikimedia Commons
each organism. This is done by extracting all the genomic DNA (metagenome) in a seawater sample, which allows for the identification of organisms present in the sample and what genetic capacity they have. Metagenomics is the study of genetic material recovered directly from an environmental sample, rather than from individual organisms within that sample.
All the sequence data locked in the genomes can then be used to look for novel enzymes, antibiotics, anti-cancer or anti-tumour proteins (called ‘gene mining’), which may enhance South Africa’s pharmaceutical or industrial industries. Current and future projects The global research trend may be divided into several future projects depending on the end goal. From a pharmaceutical point of view, the oceans have provided a range of new anti-cancer and anti-tumour drugs from marine symbiotic bacteria, and many species have yet to be tested. The more compounds and
biosynthesis pathways we discover, the easier it gets to design new compounds in the laboratories for treating against fast-growing antibioticresistant bacteria and cancers. Our knowledge of the viral and bacterial diversity in our coastal waters are limited by the techniques available to us, however new emerging technologies (such as 454 and Illumina sequencing) make it possible to do in-depth studies on the South African coast. There is also the possibility of monitoring harmful algal blooms, changes in community composition due to global warming and the effect of pollution on pristine ecosystems. From a biotechnological point of view, the extreme environments such as Antarctic soil/meltwater and deepsea sediments allow for the isolation of novel species and therefore novel genes. Depending on the goal (i.e. new enzymes for biofuel production) these genes can then be expressed and products used for downstream applications. One of the new projects at UCT is looking at the seasonal variation in these picophytoplankton communities between Cape Town and
Gerda du Plessis is a doctoral candidate at the University of Cape Town, currently researching bacterial biodiversity in the Southern Ocean. She received her Master’s degree in Biotechnology at the University of the Western Cape in 2011 and finished her Honours and Bachelors degrees at Stellenbosch University. Her work has taken her through many fields including aquaculture, soil metagenomics, yeast/wine biotechnology and lastly oceanography.
Suggested reading Montes-Hugo, M, Doney, S.C., Ducklow, H.W., W. Fraser, W., Martinson, D., Stammerjohn, S. E. and Schofield, O. (2009). Recent Changes in Phytoplankton Communities Associated with Rapid Regional Climate Change Along the Western Antarctic Peninsula. Science, 323:1470–1473. Munn, C. B. (2011). Microbes in the marine environment. In: Marine Microbiology: Ecology and applications. (Ed.) Munn, C. (Taylor and Francis Group). pp.1-23 Rusch, D.B., Halpern, A.L., Sutton, G., Heidelberg, K.B., Williamson, S., Yooseph, S. et al. (2007). The Sorcerer II Global Ocean Sampling expedition: northwest Atlantic through eastern tropical Pacific. PLoS Biol 3: e77. Venter, J.C., Remington, K., Heidelberg, J.F., Halpern, A.L., Rusch, D., Eisen, J.A. et al. (2004). Environmental genome shotgun sequencing of the Sargasso Sea. Science 304: 66–74. Whitman, W.B., Coleman, D.C. and Wiebe, W.J. (1998). Prokaryotes: the unseen majority. Proc. Natl. Acad. Sci. USA 95:6578–6583
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Fact File Q
Prokaryotes and eukaryotes
The cell structure of a bacterium, one of the two domains of prokaryotes. Image: Wikimedia Commons
A
ll organisms are either prokayotes or eukaryotes. This division reflects two distinct levels of cellular organisation.
Binary fission in a prokaryote. 1: The bacterium before binary fission with the DNA tightly coiled. 2: The DNA of the bacterium has replicated. 3: The DNA is pulled to the separate poles of the bacterium as it increases size to prepare for splitting. 4: The growth of a new cell wall begins to separate the bacterium. 5: The new cell wall fully develops, resulting in the complete split of the bacterium. 6: The new daughter cells have tightly coiled DNA, ribosomes, and plasmids. A typical animal cell.
Prokaryotes Prokaryotes are a group of organisms whose cells do not have a cell nucleus. These organisms also lack cell organelles such as mitochondria or any other organelles that are bound by a membrane. This means that all the internal components of the cell are found together within the organismâ&#x20AC;&#x2122;s cell membrane, rather than being separated into different cellular compartments. Most of the prokaryotes are single celled organisms. Prokaryotes include the two major classification domains â&#x20AC;&#x201C; bacteria and archaea. The genetic material in a prokaryote is kept within a DNA/protein complex in cytosol of the cell called the nucleoid. The complex contains a single, cyclic, double-stranded molecule of stable chromosomal DNA. In some prokaryotes, genes are stored in separate circular DNA structures called plasmids. The metabolic processes of prokaryotes take place across the cell membrane. Bacteria and archaea reproduce asexually, usually by binary fission. Bacteria Bacteria are very small, single celled organisms that range in size from half to five micrometres. There are many different shapes of bacterial cells, such as round and rod-shaped, spiral and filaments or thread-like.
Eukaryotes All other organisms are eukaryotes. Eukaryotes are organisms whose cells contain complex structures that are enclosed within membranes. The defining structure that sets eukaryotes apart from prokaryotes is the nucleus. All large, complex organisms are eukaryotes including animals, plants and fungi. There are also may single celled organisms in among eukaryotes. Plant and animals cells have similarities and differences but both are eukaryotic cells.
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A typical plant cell. Image: Wikimedia Commons
Image: Wikimedia Commons
Geographic Information Science
PLATO accredited course GISc is the science of capturing, processing, analysing and mapping spatial data (information about the earth). The associated technology is used to explore, visualise and analyse data. Do you enjoy Geography, Computer Science, Maths, Science, Physics and Information Technology? Do you like variety, design and working indoors, as well as outdoors? You could become a Geographic Information Systems (GIS) professional after completion of your GISc studies. A growing variety of careers are available within a very wide range of industries, including planning, engineering, land development and management, as well as mining, architecture and mapping, both in the private and public sector. Studying GISc at CPUT gives students the opportunity to specialise in either spatial analysis, remote sensing or data quality management. Both our Diploma (exclusive to CPUT) and BTech courses have been accredited by the South African Council for Professional and Technical Surveyors (PLATO).
For more information, visit: http://bit.ly/CPUT-GISc Contact: J Raubenheimer Tel: +27 21 959 6207 E-mail: RaubenheimerJ@cput.ac.za
Plankton contains a wide variety of different species. Image: Franck Prejger, Observatoire Oceanographique Villefranche-sur-Mer
New ways to study zooplankton New devices are helping scientists to study zooplankton in the Southern Ocean. By Margaux Noyon
T
he biology of the Southern Ocean has been studied since the 1870s but we still do not know all its secrets. Indeed, because of where the Southern Ocean lies and the conditions at these latitudes, there have been relatively few exploration cruises in these waters compared with other oceans. Most of the data available has been collected in spring and summer, when the weather is relatively calm. What is zooplankton and why do we need to study it in the Southern Ocean? Zooplankton is the collective term used for all the heterotrophic organisms in the ocean that drift with the currents. The zooplankton eat phytoplankton â&#x20AC;&#x201C; microscopic algae â&#x20AC;&#x201C; so they are the main link in the food
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chain between phytoplankton and the top predators. The top predators are fish, whales, seals and seabirds. Many of the fish and whales eat krill, which is a major component of the zooplankton. And krill themselves eat smaller species in the zooplankton. So zooplankton are a very important part of the ecosystem of the Southern Ocean. Heterotrophic organisms are organisms that cannot manufacture their own food. They need to eat. The phytoplankton are autotrophic organisms. They can manufacture their own food by photosynthesis.
There are various different species of organisms in the zooplankton. With the continuing rise of carbon dioxide (CO2) emissions on the
planet, it is worth remembering how important oceans are in the global carbon cycle. Oceans can absorb up to 30% of all anthropogenic (human produced) emissions. The oceans fix atmospheric carbon through two processes, called the physical and biological pumps. In the physical pump warmer water, flowing from higher latitudes, gets cooler and becomes more dense as it moves towards the poles. The denser water then sinks, transporting the dissolved CO2 into the deep ocean. This pump is important in the sequestration of carbon. Sequestration is the process of capture and longterm storage of atmospheric CO2. Colder waters can take up more dissolved carbon than warmer water, so there is more sequestration of carbon in polar regions.
B
A A: A pteropod. B: A copepod.
Image: A www.pmel.noaa.gov B Wikimedia Commons
Left: The left side of this diagram shows the biological pump in the Southern Ocean and the right side shows the simpler physical pump. Image: ©S.Chisholm, Nature 407, October 2000
Krill Krill are tiny crustaceans (order Eupausiacea). They are found in all the world’s oceans and a very important part of the ocean food chain. They are near the bottom of the food chain because they feed on plankton and smaller zooplankton species. Krill are then eaten by larger predators. There is one species of krill in the Southern Ocean – the Antarctic krill (Euphasia superba) – that has an estimated biomass of over 500 000 tonnes. Of this, over half is eaten by whales, seals, penguins, squid and fish each year. Krill migrates vertically through the ocean layers – near the surface during the night and in deeper waters during the day.
show that the Southern Ocean (south of 40°) might account for more than 40% of the total uptake of all oceanic waters. Many uncertainties remain in these calculations, however. This means that there is a real and urgent need to improve these models. Some aspects of the biological pump are still hotly debated by scientists. For instance, what motivates biologist oceanographers is that despite the high level of macronutrients in the Southern Ocean, which feed photosynthetic processes, primary production remains low. These areas are thus called ‘high nutrient – low chlorophyll’ (HNLC) areas. One of the main hypotheses is that other micronutrients, like iron, limit photosynthesis and thus primary production. The consequence ▲ ▲
The biological pump is more complex. The biological pump refers to interactions in the upper water column where light penetrates. The pump starts with the fixation of dissolved CO2 by photosynthesis in phytoplankton. As we have already learnt phytoplankton is then eaten by heterotrophic zooplankton, which is the main food source of various predators. Part of this pool of carbon is released into the atmosphere when organisms respire, while another part sinks vertically into the deep ocean. This vertical transport is made up of various types of detritus, faecal pellets, carcasses of organisms and algae skeletons. This is called ‘marine snow’. If the export of carbon into the deep ocean is more than the emission of carbon, the area can be considered as a carbon ‘sink’. Some calculations
The Antarctic krill (Euphasia superba).
A krill swarm.
Image: Wikimedia Commons
Image: Wikimedia Commons
Quest 9(1) 2013 25
What you see when you examine a sample from a plankton net.
A plankton net.
for climate is direct because less atmospheric CO2 is taken up through the biological pump processes. We know that the zooplankton are the main food source for large marine mammals, fish and seabirds. Most of these predators are migratory organisms – they travel south during the austral summer to feed and go back north to reproduce. If the Southern Ocean is a feeding ground for predators, it is logical to assume that the area should have plenty of zooplankton available. But how can zooplankton be so abundant with so little food in the water? One of our main challenges remains to obtain a better estimation of the zooplankton biomass.
Image: Margaux Noyon
Studying zooplankton using a microscope.
Image: Margaux Noyon
A diagram showing the working parts of the continuous plankton recorder (CPR). Image: Sir Alistair Hardy Foundation for Ocean Science
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New ways to study zooplankton Zooplankton and phytoplankton are not uniformly distributed in the ocean either in space (vertically and laterally) or in time. They can occur in low numbers or be present in vast aggregations. They can also ‘bloom’ at certain times of the year and then appear to be completely absent during other times. We need to know why. To understand why these massive changes take place we need to increase our sampling efforts. We need to sample more often and we need to sample at many different scales, from a few centimetres to thousands of kilometres. Satellites have been quite effective in improving our knowledge of primary producers in the surface and sub-surface waters of the ocean but as yet we have no way of using a similar instrument to study zooplankton. The traditional way of collecting zooplankton samples is to use plankton nets. These nets can collect different sizes of zooplankton depending on the mesh size and the
Image: Margaux Noyon
size of the opening of the net. But nets take samples that are snapshots in time. It is common to have up to 200% variability in catches between two nets towed together (spaced only a few centimetres apart). In addition, counting and identifying the species of each sample under a stereomicroscope is an intensive task and requires skills that are becoming more and more scarce. Early plankton counters
Driven by a need for new sampling techniques, Alister Hardy started the development of a new generation of sampling devices. On the ‘Discovery’ cruises between 1925 and 1927, he used the first prototype of his counter plankton recorder (CPR) to sample Antarctic krill. The CPR was designed to be towed behind any commercial ship at 10 m depth to collect as much data as possible. The CPR collects plankton on a long silk strip which is continuously rolled from one bobbin to another, the rate being determined by the ship’s speed. The silk is then extracted from the CPR and sent to scientists who are able to identify the organisms. The CPR has a very basic and robust design, which has not changed in over 80 years, allowing researchers to compare data over many years. It has been at the centre of numerous studies of long-term data series linked to global climate change, especially in the North Atlantic, where the first survey started in 1931. Since 1991, CPRs have been towed in the Southern Ocean (SCAR, Southern Ocean Continuous Plankton Recorder Survey, initiated by the Australian Antarctic Division). The South African Department of Environmental affairs (DEA) recently acquired a CPR which will be towed regularly by the new
A ZooScan.
Image: Carmen Garcia-Comas
SA Agulhas II in the Southern Ocean. However, one of the downsides of the CPR is that only the plankton in the sub-surface layer are described. With further technological advances in the early 20th century the first underwater low-frequency sound detector appeared. Initially used for military purposes and now extensively used by fishermen, SONAR instruments were revealed to be a powerful tool for the biological oceanographer. In contrast to the CPR, information on the vertical distribution of zooplankton could be obtained. The SONAR ‘transducer’, located on the hull of a ship, emits a low-frequency sound into the water. Each time this sound hits an object an echo is reflected back to and registered by the transducer. The acoustic signal is then analysed by researchers to determine the size of the organisms, the biomass and the depth. Although there have been promising improvements recently, small organisms are still relatively difficult to detect by acoustic means and the level of resolution is relatively low compared with net samples. It is often necessary to obtain a physical sample, by towing a net through the water, to validate the acoustic signal. The echosounder has however been widely used in the Southern Ocean for krill surveys as the krill’s acoustic signature is quite distinctive from other organisms. The next generation
The laser optical plankton counter
The LOPC is simple to understand. The instrument is towed underwater and water (with plankton) passes through a tunnel equipped with a laser reading system. Each time a particle within the range of 100 µm to <3 cm in size crosses the laser beam, its size is measured and recorded. The LOPC can be towed at up to 12 knots, which allows surveys of very large areas. Data are recorded continuously but the internal processor collates data every half second. At a 12 knot towing speed this equates to a spatial resolution of 3 m. The LOPC is compact enough to be mounted on autonomous underwater vehicles
▲ ▲
The latest generation of automated instrumentation are optical. There are two different types of optical instruments: one is laboratory based and the other is towed underwater. To overcome the difficulties of counting zooplankton net samples,
researchers and engineers invented the ZooScan. A zooplankton sample is poured into a cuvette, the organisms are roughly separated from each other within the cuvette and the sample is scanned. The digitised images are then processed automatically using image-analysis software which counts, measures and identifies the type of organism. It is rapid (about 15 - 20 min per sample), iand is not affected by operator error, which greatly improves comparison between samples but does not identify the species of zooplankton. This type of instrument is also very suitable for long-term surveys or even to re-analyse old zooplankton samples to obtain a good and thorough timeseries. Among the towed instruments, there are two noteworthy ones – the laser optical plankton counter (LOPC) and the video plankton recorder (VPR). In South Africa, we have one LOPC at the University of Cape Town, which was used for the first time on the SA Agulhas II in July 2012.
From the top: A LOPC on an autonomous underwater vehicle. Image: S. Basedow, University of Nordland and a SOLOPC An LOPC mounted on the lower part of a sounding oceanographic lagrangian observer (SOLO) float. Image: D.Checkley, L&O (2008)
Illustration of the Rolls-Royce LOPC.
Image: A. Herman, Bedford Institute of
Oceanography
Quest 9(1) 2013 27
or even on an oceanographic float, such as the sounding oceanographic lagrangian observer (SOLO), so reducing the ship time required. The disadvantage of the LOPC is that, like the echosounder, it needs plankton nets so that the particles that are counted can be identified.
the instrument can be towed at a speed of up to 12 knots and takes picture at a rate of 30 per second. At a speed of 12 knots, for example, a picture is taken every 20 cm. From each image, each object is isolated and then analysed. This instrument generates an enormous number of images, which cannot be sorted manually in a reasonable time. So scientists then use automatic image-analysis software (similar to the ZooScan) which has been extremely successful at measuring, classifying and determining the type of organisms in each picture. Researchers have been able to see details of organisms that have never been seen before. It is not always possible, however, to identify the exact species.
The video plankton recorder
The future
The VPR can be thought of as an ‘underwater microscope’ which can detect plankton from as small as 100 µm and up to few centimetres in size. The instrument is composed of two arms parallel to each other, with a camera and a strobe light mounted facing each other on each arm. The latest version of
With ever-improving technology, more automated and efficient instruments will become available to study zooplankton on the micro- to the large-scale (few centimetres to thousands of kilometres) and hopefully at a lower cost. The polar regions provide an excellent laboratory to experiment and work on
The video plankton recorder (VPR). Image: ©C. Ashjian, Woods Hole Oceanographic Institution
these instruments. The low biodiversity of these areas means that fewer species have the same optical or acoustic signal and are thus relatively easy to differentiate from each other. We urgently need to predict the impact of climate change on our planet – being able to map the zooplankton biomass in the Southern Ocean will be a great step forward. It will help us understand the ecosystem dynamics of zooplankton and thus help scientists to predict more accurately the future impact of global climate change. ❑ Margaux Noyon is from France, where she did her PhD at Villefranche-sur-Mer, focused on zooplankton in the Arctic Ocean and more precisely on the adaptation of zooplankton to high latitudes. She came to South Africa at the end of 2010, seeing an opportunity to work in the Southern Ocean. Her main scientific interest is the ecology of zooplankton in the ocean and understanding its role in pelagic ecosystem functioning. She recently started working with the LOPC and will investigate the distribution of zooplankton around the Prince Edward Islands.
WALTER SISULU UNIVERSITY Walter Sisulu University offers fully accredited diplomas, degrees and postgraduate studies in a wide range of science programmes in its Faculty of Health Sciences and Faculty of Science, Engineering and Technology: Faculty of Health Sciences: MBChB; B Cur (Basic); Bachelor of Medical Sciences (Physiology, Biochemistry or Microbiology); Bachelor of Medical Clinical Practice; Bachelor of Social Work; Bachelor of Science in Health Promotion. Faculty of Science, Engineering and Technology: National Diplomas, degrees and postgraduate studies in Chemistry & Chemical Technology, Environmental Sciences, Physics, Biological Sciences (Pest Management), Botany, Zoology, Information Technology & Computer Science, Engineering Civil, Electrical, Mechanical, Construction Management & Quantity Surveying, Applied Mathematics and Statistics, Food & Consumer Science as well as technological programmes in Fashion and Art. For affordable, fully accredited, quality higher education contact us today and apply before 31 October. Faculty of Health Sciences: Tel: 047 502 2111/2844 (Mthatha) Faculty of Science, Engineering and Technology: Mrs GK Lindani-Skiti, Tel: 043 702 9257, Fax: 043 702 9275, E-mail: glindani@ wsu.ac.za Offered at Buffalo City (East London), Butterworth and Mthatha Campuses.
www.wsu.ac.za 28 Quest 9(1) 2013
IDC – financing South African innovation The IDC’s Venture Capital Strategic Business Unit (SBU) manages a R750 million fund providing equity funding to start-up companies for the development of globally unique South African Intellectual Property (IP) – this being the key criteria for any application.
Funding is provided in the form of ordinary shares and shareholder loans. There is no stipulated investment period, but the SBU’s objective is to achieve an exit opportunity within a reasonable time frame.
The funding provided by the SBU facilitates completion of the development, followed by the commercialisation of technology-rich products. These innovations and inventions most often stem from academic researchers who have developed their work to a point where they have a desire to become entrepreneurs; and innovators or inventors who want to move from tinkering with their ideas and prototypes in their backyards to fully commercialised businesses.
Through its investments, the Venture Capital SBU plays a proactive role in driving industrial development in South Africa, having a meaningful impact through the development of new entrepreneurs and shifting the focus from large companies to SMEs. This is achieved through sustainable development of more knowledge-intensive industries for long-term growth and job creation as prioritised in the Government’s New Growth Path (NGP). The unit continues to be a proactive, value-adding partner to its clients, capable of producing huge development returns to the benefit of South Africa’s economy and citizens.
The critical investment criterion for all Venture Capital projects is that the IP must be owned by the company and if not patentable, the product needs to provide a sustainable competitive advantage. The unit’s mandate allows for investment in projects across all industries, leading to sectoral growth and job creation. Recent South African inventions and innovations in the electronics, ICT, medical device and biotechnology sectors have proven particularly successful.
Chillibush7428IDC
Funding for a project can reach a maximum of R40 million over several years, with the initial investment limited to R15 million. The IDC takes a minority shareholding of between 25% and 50% depending on the SBU’s valuation of the business and the amount of funding required. The start-ups stand to benefit from the further strategic support, guidance and advice provided through a partnership relationship with the IDC.
Telephone: 086 069 3888 Email: callcentre@idc.co.za To apply online for funding of R1 million or more go to www.idc.co.za
Invasive aliens in Antarctica Right: General map of Antarctica showing the Antarctic Continent and Peninsula, the sub-Antarctic islands and the Southern Ocean. Image: courtesy of the Australian Antarctic Data Centre: http://data.aad.gov.au
A tagged invasive house mouse (Mus musculus) on Marion Island. Tags are used for mark and recapture studies, which allow scientists to collect data on the population sizes of these small invasive mammals. Mice are having significant impacts on the ecosystems of many sub-Antarctic islands. Image: Anne Treasure
Even the remote Antarctic continent, the sub-Antarctic islands and surrounding seas are troubled by invasive alien species. By Anne M Treasure
T
he introduction of invasive alien species has been recognised as a major threat to biodiversity and ecosystems and the resulting effects have been recorded around the world. In fact the Global Invasive Species Programme (http://www.gisp.org) has identified that the spread of invasive alien species is one of the most significant ecological and economic threats to the planet. Humans have served as both accidental and deliberate dispersal agents of invasive alien species and the frequency and extent of introductions worldwide are alarming.
Definitions Endemic species: A species that is only found in a particular geographic location and nowhere else in the world. Indigenous/native species: A species that occurs naturally in an area, without human intervention. Not all indigenous species are endemic species, as an indigenous species can naturally occur in more than one area. Alien species: A species of plant, animal or any other type of organism found in an area where it did not naturally occur in the past. Its presence in this area is due to deliberate or unintentional human involvement. Naturalised or established species: An alien species that has maintained a reproductive population for at least 10 years without direct intervention by people. Invasive species: An alien species that manages to maintain a large reproducing population with the potential to spread over large areas.
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What are invasive alien species and why are they a problem? Alien species (also called introduced, exotic, non-native, or non-indigenous species) are those plants, animals or any other types of organism, that are found in areas where they did not occur naturally in the past. These species were introduced through the accidental or deliberate actions of humans. An alien species that manages to maintain a large reproducing population with the potential to spread over large areas is known as an invasive species. Invasive species can cause a number of problems costing millions of rands of damage every year by, for example, being agricultural pests or vectors of disease. Invasive species that spread can outcompete and exclude indigenous species that occur in the area naturally. In this way, natural species interactions are disrupted, changing ecosystems and the services they deliver. Invasive species can also lead to the extinction of indigenous species. Invasive species are found in every taxonomic group, from viruses, fungi and plants to invertebrates, birds and mammals. These species have had substantial impacts in virtually every region and habitat on earth. Despite its remoteness, Antarctica is no exception.
Invasions in the Antarctic The Antarctic region includes the Antarctic Continent and Peninsula, sub-Antarctic islands and the Southern Ocean. Alien microbes, fungi, plants and animals occur on most sub-Antarctic islands and some parts of the Antarctic continent and ocean. The consequences of invasive species in Antarctica are widely reported, and impacts on indigenous species and communities have been recorded. There has therefore been much interest in the region, particularly as it is of considerable conservation importance due to the large number of indigenous and endemic species found there. In the past, rats and mice were inadvertently introduced from visiting ships to many sub-Antarctic islands. Islands have also seen the intentional introduction of species such as rabbits (on Kerguelen and Macquarie) and reindeer (on South Georgia and Kerguelen) for food, or cats on Marion and Macquarie islands. Once feral, these animals started causing widespread environmental damage. For example, introduced cats on Marion and Macquarie islands substantially reduced seabird populations before they were finally
Q Antarctic biology
The invasive springtail Pogonognathellus flavescens coated with fluorescent powder, on Marion Island. Using a black-light-blue bulb that picks up the fluorescence at night, it is possible for scientists to track the movements of such invertebrates. Such studies provide vital information about the patterns and speed at which invasive species spread. Image: Anne Treasure
(33 824) (available on http://iaato. org). Furthermore, government operators now employ around 5 000 scientists and support staff, who visit the region for short or long time periods, and there are over 65 yearround and summer-only research stations in Antarctica. Each of these stations has to be resupplied at least once a year with personnel, food, cargo and building materials. The number of ships as well as aircraft entering the region has increased, meaning that there are many more opportunities for alien species to be introduced. In addition, many tourist and research vessels go from place to place covering a number of different Antarctic and sub-Antarctic locations. Therefore, species that are already pre-adapted to cold conditions in their native region may be transported to other regions within Antarctica where they do not occur naturally. Although many countries now have stricter controls to prevent introductions than were in place in the past, terrestrial alien species are still brought into Antarctica in cargo and attached to clothing, and marine species are introduced by hull fouling, the intake and subsequent discharge of ballast water, scientific equipment or they can be transported on floating man-made debris. Marine introductions are of a particular concern as most visitors and cargo are transported to the Antarctic in ships. However, much less is known about marine invasions than about terrestrial invasions. This is in part due to poor knowledge of the diversity of many near-shore environments in Antarctica, which makes it difficult to identify
Scientists collecting data on invasive invertebrates and plants on sub-Antarctic Marion Island. Furthering scientific understanding of invasive species helps to reduce the rates and impacts of biological invasions. Image: Anne Treasure
whether invasive species have been introduced. The first alien marine species to be recorded in Antarctic seas was the North Atlantic spider crab (Hyas araneus). Both a male and a female of this shelf species, native to the North Atlantic and Arctic Oceans, were found on the Antarctic Peninsula in 2004. It is suspected that this species entered Antarctic waters either on shipsâ&#x20AC;&#x2122; sea-chests or through ballast water. The invasive green alga Enteromorpha intestinalis is also thought to have been introduced via the hulls of visiting ships and now grows in dense mats on intertidal rocks on the South Shetland Islands. These pathways for marine invasions are a significant threat. A study on the highly invasive Mediterranean mussel (Mytilus galloprovincialis) showed this species to predominate in the sea chests of the South African polar vessel the SA Agulhas and that at least some of these individuals survived multiple voyages to the Antarctic region. The survival of this species in Antarctic conditions demonstrated that the mussels are capable of surviving polar conditions, at least in the short â&#x2013;˛ â&#x2013;˛
eradicated by the early 1990s on Marion and by 2000 on Macquarie. Rabbits and reindeer cause severe damage to native vegetation. Invasive mice have been introduced to numerous islands such as Marion, Macquarie, South Georgia, Crozet and Kerguelen where they are having severe impacts on indigenous invertebrates and plants. Mice and rats also pose a serious threat to seabirds on which they are known to prey. The Kerguelen archipelago is the island group with the highest number of invasive mammals and is suffering large consequences due to seven invasive mammal species now present on the islands: mice, rats, rabbits, sheep, reindeer, mouflon and cats. Invasive plants and invertebrates (mostly introduced unintentionally through, for example, animal fodder, cargo (including food supplies) or attached to clothing, are widespread on most islands and have also been found on the Antarctic Peninsula. These introductions have had considerable impacts, which include direct reductions in population sizes of indigenous species, as well as changes in food webs and the functioning of ecosystems. The introduction of fungi, microorganisms and diseases have also been linked to human activities. These threats are set to continue as the Antarctic is facing an increase in the rate of introduction of invasive species. This is mostly because the routes for colonisation have increased substantially due to increased human traffic to Antarctica. Tourist numbers have increased three-fold from 1998/1999 (10 013) to 2010/2011
Quest 9(1) 2013 31
Invasive eradication: Dr Jenniffer Lee What is your current job and what does it entail? I work as the Environment Officer for the Government of South Georgia and the South Sandwich Islands. I am responsible for all matters related to managing the terrestrial environment, including biosecurity and habitat restoration. Lots of my work is about policy and ensuring that the government meets its obligations to international agreements such as the Agreement on the Conservation of Albatross and Petrels. About half of my time is spent in the office planning and writing policy documents and the other half is spent in the field overseeing various environmental management projects.
Dr Jeniffer Lee.
What invasive problems do you face on the islands and what impacts are these invasions having? Although there are now strict measures in place to prevent the introduction of alien species, early whaling and sealing expeditions introduced a number of non-indigenous species to South Georgia. Some species such as rats and dandelions were introduced accidentally, whereas others such as reindeer were deliberately introduced as a source of food. At the time, nobody knew what impact these species would have, but in the absence of natural predators or disease populations have grown
32 Quest 9(1) 2013
What skills and aptitudes do you need to do a job like this? To work as an environment officer you need to be able to think on your feet and face up to a challenge. The daily workload is incredibly varied and can involve anything from issuing permits so scientists can collect samples for their research to planning how to herd reindeer across a rugged mountain pass. One of the big attractions of the job is being able to spend time on South Georgia. However, when in the field the hours are long and the accommodation is basic (usually a tent!). It is important to be able to work independently, be physically fit and able to look after yourself and those around you in a remote environment.
of organisms found on the bottom of a barge taken from Hobart, Australia, to Macquarie Island for this purpose (including algae, barnacles, numerous crustaceans, starfish, mussels, and crabs) highlighted this risk. Attempts to introduce salmonid fish have been made at a number of islands, including the Falklands, Kerguelen, Possession, Crozet, South Georgia and Marion. These fish only flourished on Kerguelen, which has relatively large rivers. Once introduced to a few rivers, the fish were able to expand their territory to neighbouring rivers by short sea migrations. Implications of climate change The low temperatures in Antarctica represent a significant challenge to survival for alien species. However, the Antarctic is facing rapid climate change, which is predicted to facilitate the introduction of invasive species. Interactions between climate change and invasive species are poorly understood, but evidence for such interactions is accumulating. For example, warming
conditions can facilitate colonisation success and give invasive species a physiological advantage over indigenous species. Warming conditions can also facilitate easier dispersal of invasive species. This is already well documented on sub-Antarctic islands for invasive plants and invertebrates. Warming waters would also favour increased transport, establishment and spread of marine alien species. Increasing temperatures can also enable species to expand their ranges into new areas faster than would occur naturally, which can have serious consequences for native species that have not evolved defences against such intrusions. For example, warming of the Western Antarctic Peninsula shelf waters appears to be facilitating the movement of the cold-intolerant king crab (Neolithodes yaldwyni) into this area. This crushing predator is having devastating ecological effects on the shelf, where they voraciously prey on echinoderms (the group of animals that includes the starfish and sea urchins). Antarctic marine invertebrates are inherently weakly calcified, making them
â&#x2013;˛ â&#x2013;˛
The highly invasive Mediterranean mussel (Mytilus galloprovincialis) was found to predominate in the sea chests of the South African polar vessel the S.A. Agulhas. Some of these individuals survived multiple voyages to the Antarctic region. Image: Photo courtesy of Dr Jenniffer Lee who carried out this study.
How are you controlling these? Currently there are programmes in place to eradicate both rats and reindeer from the island. Rats will be eradicated by dropping poison bait from helicopters. This is the largest rat eradication programme that has ever been attempted. Reindeer will be controlled by herding them from outlying areas to a central point where they will be killed under veterinary supervision. Controlling invasive species is very costly. The rat and reindeer eradication projects will cost millions of pounds. There are also environmental impacts of eradication attempts. When poison bait is dropped to kill the rats, it will probably also be eaten by some of the native birds such as pintails and sheathbills. When these birds and the rats die, larger birds will eat the carcasses, causing the poison to build up in the food chain. However, even though it is expected that some birds will die, it is likely that populations will recover rapidly once the rats have been removed. What is your background and what previous work have you done on invasions? I did my PhD and post-doctoral research at the Centre for Invasion Biology at Stellenbosch University. I worked closely with the South African National Antarctic Programme to look at how invasive species moved into and around the Antarctic region. I was lucky enough to be able to work on both marine and terrestrial systems and looking at what sort of alien species were being transported inside ships going to the Antarctic and what was being carried underneath them on their hulls.
Image:Jeniffer Lee
term. This study also highlighted the limited effectiveness of antifouling technology employed by such vessels. Another potential source of marine introductions is transport used on re-supply expeditions for ship to shore transfers. The presence of large numbers
rapidly and there are severe impacts on the islandâ&#x20AC;&#x2122;s native flora and fauna. In particular rats and reindeer both have severe impacts on the islands burrowing bird species. Rats eat chicks and eggs and reindeer graze vegetation above the burrows, causing the ground to dry out and the burrows collapse. Reindeer also facilitate the spread of non-native plant species like the annual blue grass, which thrives in the disturbed ground.
Marion Islandâ&#x20AC;&#x2122;s pristine and breathtaking landscape.
Image: Anne Treasure
particularly susceptible to the crabs. The crabs are also modifying the physical environment and altering other animalsâ&#x20AC;&#x2122; habitat by disturbing sediment on the seafloor when they dig for worms and other creatures. Intrusion of subAntarctic waters into Antarctica has also resulted in alien species, most probably of South American origin, being found off King George Island. Control and the future Eradicating an alien marine or terrestrial species once it has become invasive is difficult and costly, and most times impossible. In fact, there are no reports of successful removal of a marine invasive species from the sea once they have invaded. Therefore, the best way to combat the problem is to prevent alien species from reaching Antarctica in the first place. Awareness of the risks that visitors may pose to ecosystems in Antarctica and the sub-Antarctic through the introduction of alien species has increased in recent years. Because of this, some national and tourism operators have implemented quarantine procedures such as boot washing and educational programmes. Various types of inspection, washing and extraction procedures can be done to minimise terrestrial introductions. Cargo should be cleaned properly and fumigated if necessary. Prevention should focus on pre-departure measures first, but biosecurity officers with biological backgrounds should also accompany all voyages to the region to undertake supervision of clothing and equipment cleaning en route. Good examples of further policies are ones that South
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Africa has in place for Marion and Prince Edward Islands such as banning the importation of fresh produce (which could contain invasive insect pests or fungi) and chicken on the bone (which could introduce bird diseases), and irradiating fresh chicken eggs (also to prevent bird diseases). Modern shipping can quickly move species thousands of kilometres against natural barriers to migration such as currents. Measures can be taken to prevent marine invasions such as painting the hulls of ships with anti-fouling paints to prevent marine organisms from attaching to the boats. Guidelines are also in place for the management of ballast water in Antarctica (see http://www.ats. aq/documents/recatt/Att345_e.pdf). Awareness of the potential risks are crucial, and simple changes to operating procedures may reduce the chance of introductions in the future. For example, changing the length of time that ships stay in port before visiting Antarctica thereby reducing the opportunity for invasive species to establish on hulls. If limiting or reducing the number of visitors to the region is not possible, then education to increase awareness for all involved in activities in the region is key, including managers of national programmes, visitors (tourists and scientists), crew of boats (tourist, scientific and fishing), tour operators and cargo facility staff. Various resources are available for this, including documentation (see for example pamphlets on: http://iaato. org/dont-pack-a-pest, http://iaato.org/ decontamination-guidelines, http://
www.asoc.org/storage/documents/ tourism/ASOC_Know_Before_You_ Go_tourist_pamphlet_2009_editionv2. pdf) and videos (for example instructional video on cleaning (Aliens in Antarctica Project, 2010: http:// academic.sun.ac.za/cib/video/Aliens_ cleaning_video%202010.wmv)). If prevention has not been possible, then early detection and quick response is vital. Having good baseline data on indigenous species is important and regular monitoring of sites (particularly high risk sites such as around research stations or tourist visitation sites) is essential. If an invasive species is detected, an eradication programme should be implemented as soon as possible to prevent the species from spreading and to make the eradication more cost effective. The quicker the response, the more effective the eradication will be. Follow-up surveys should be conducted to ensure that the eradication was successful. If eradication is not possible, regulation and control of the invasive populations should be explored. Much research is being conducted on invasive species in Antarctica and the impacts they have on indigenous species and ecosystems (see for example www.sun.ac.za/cib). Findings from this research inform policy and international collaborative programmes to combat the problems. An inter-disciplinary committee called the Scientific Committee for Antarctic Research (SCAR: www.scar.org) is charged with initiating, developing and coordinating high-quality international scientific research in the region. SCAR also provides scientific advice to Antarctic Treaty Consultative Meetings and makes recommendations that influence policy and international agreements, which provide protection for the ecology and environment of the Antarctic. Working in this field is very rewarding as one can make a real difference to the conservation of this unique and beautiful part of the world. â?&#x2018; Dr Anne Treasure is a postdoctoral research fellow in the Oceanography Department at the University of Cape Town. Her research focuses on ecosystem responses to climate change-driven shifts of the sub-Antarctic front in the vicinity of the Prince Edward Islands. She completed her PhD on the impacts of invasive species and climate change on Marion and Prince Edward Islands.
Subantarctic fur seals torpedoing off the coast of Marion Island.Image: Nico de Bruyn
The Marion Island seal populations have been studied for the last 30 years. Cheryl Tosh and MarthĂĄn Bester describe their field research.
High in the food chain â&#x20AC;&#x201C; seals in the Southern Ocean D
eep in the Southern Ocean, Marion Island is a platform for breeding seals and seabirds such as penguins and albatrosses, with killer whales patrolling the inshore waters. Because many species have their young on land there is always life in some form at Marion Island
throughout the year. The seal species at Marion Island have their young on land and forage at sea. There are three seal species: the southern elephant seal (Mirounga leonina), the Antarctic fur seal (Arctocephalus gazella) and the Subantarctic fur seal (Arctocephalus tropicalis).
Studying Marion Island seals Southern elephant seals have been intensively studied at Marion Island for the last 30 years, under the leadership of Prof. MarthĂĄn Bester. Intensive markrecapture studies follow the comings and goings of elephant seals on the island. As a result of these studies scientists are starting to understand the survival rates of different age and sex classes of the population and the importance of migration and immigration in controlling the population size. These processes are affected by changes in food resources, which can either be shown by changes in body condition or changes in behaviour. The behavioural responses of southern elephant seals are studied using state-of-the-art satellite relay data loggers that are attached to the animals. The devices are linked with satellites, and send data about the position of the animal, the water temperature and salinity, and the diving behaviour of the animal, which provides scientists with valuable information about the habitats that these seals are using and how their behaviour changes over time. Southern elephant seals
A southern elephant seal bull, Mirounga leonina, with a salinity, temperature, depth recorder attached to its head. This device will communicate with a satellite and will tell us where this seal foraged and will provide researchers with information about the characteristics of the water column. Image: Nico de Bruyn
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Southern elephant seal behaviour shows an enormous amount of individual variation. Some individuals
Antarctic furseals (Arctocephalus gazella) playing in the water.
Fur seals While the southern elephant seals represent the heavyweights of Marion Island, the fur seal species, the Antarctic and Sub-antarctic fur seals,
Image: Nico de Bruyn
represent strength in numbers. Fur seal populations at Marion Island have exploded in the last couple of years, contrary to predictions about climate change affecting food resources ▲ ▲
concentrate on feeding in highly productive and stable areas where different marine currents meet – called marine frontal structures. Others feed in short-lasting mesoscale eddies – the unstable areas of the ocean currents that surround the island. Some individuals concentrate on foraging in areas of the ocean that have a particular temperature or current or are at a specific depth. The way that this population spreads its feeding efforts in different parts of the same environment may well be the key to its long-term success. Because different individuals can use a variety of habitats they may not compete directly with each other for the same resources. This variation in foraging behaviour will also help the population to withstand changes in their environment. Recently, researchers at Marion Island have also started to measure changes in body condition of these seals using novel photogrammetrical methods. Dr Nico de Bruyn has developed a protocol using photographs taken with calibrated cameras to build a three-dimensional model that shows the volume of elephant seals. Elephant seals are loyal to their birth and breeding sites, so the same animals can be photographed repeatedly in order to build up a time series of three-dimensional models, which may eventually be used to describe body mass changes in response to environmental conditions and behaviour. Researchers have already established that the larger southern elephant seal cows are less likely to breed every year at Marion Island, but in spite of this these cows probably produce more pups than smaller cows over a breeding lifetime.
The Prince Edward Islands The Prince Edward Islands are two small sub-Antarctic islands that are part of South Africa – Prince Edward Island and Marion Island. The island group is about 955 nautical miles (1 769 km) south-east of Port Elizabeth on mainland South Africa. Marion Island (46°54’45”S 37°44’37”E), the larger of the two, is 25.03 km long and 16.65 km wide, with an area of 290 km2 and a coastline of some 72 km, most of which is high cliffs. The highest point on Marion Island is Mascarin Peak, reaching 1 230 m above sea level. Boot Rock is about 150 m off the northern coast. Occurring at the juncture between the African Continental Plate and the Antarctic Plate, Marion Island has been volcanically active for 18 000 years. The first historical eruption was recorded in November 1980 when researchers recorded two new volcanic hills and three lava flows. Researchers observed another small eruption in 2004. Besides volcanic cones, Marion Island is home to Marion Base, part of the South African National Antarctic Programme. Focusing on biological, environmental, and meteorological research, the base is situated on the island’s north-eastern coast. A dusting of ice graced the summit of Marion Island in early May 2009 as waves breaking against the island’s shore formed a broken perimeter of white. Like its smaller neighbour, Prince Edward Island, Marion Island is volcanic, rising above the waves of the Indian Ocean off the southern coast of Africa. Prince Edward and Marion are part of South Africa’s Western Cape Province. The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite acquired this natural-colour image on May 5, 2009. Sunlight illuminates the northern slopes of the volcanic island, leaving southern slopes in shadow. More than 100 small, reddish volcanic cones dot the island, some of the most conspicuous in the north and east. The island reaches its highest elevation, 1 230 m, near the centre. Vegetation is generally sparse on Marion Island. Lichens live near the summit, and mosses and ferns grow elsewhere on the boggy surface, but trees don’t grow on the island. Image: NASA
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Seal researchers at Marion Island spend a lot of time in the field and become well acquainted with the rough terrain of the island. Image: Nico de Bruyn
Researchers attaching a satellite relay data logger to a fur seal female restrained in a hoop net. The devices are attached to the outer fur with epoxy resin and are removed when the seal returns to Marion Island by catching the seal in the hoop net and gently shaving away the outer guard hairs that are attached to the epoxy. Image: Nico de Bruyn
they have been eating by analysing fish ear bones (called otoliths), squid (cephalopod) beaks and other remains sampled from droppings (scats) collected on the beaches. The otoliths and cephalopod beaks are specific to different species. Orcas – mammalian predators in the sea
A southern elephant seal cow and newborn pup. Researchers maintain a respectful distance while watching the cow bond with her pup. An Antarctic skua (Stercorarius antarcticus) looks on – ready to pounce if the opportunity arises.
negatively. These agile swimmers are often seen torpedoing along the Marion Island coastline until they haul out at their beach of choice. Large colonies of seals form during the breeding season, when males aggressively protect small harems of four or five females. Some beaches are densely packed with harems and males are not able to cross another male’s territory once it is established. Any male crossing a territory is seen as a challenger and will be viciously attacked. Such attacks can be fatal. The high drama of the breeding season abates as soon as most of the females have pupped or been mated. After the harems break up the females that have suckled their pups for a few days will
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leave to forage. The little pups then have a long wait until their mothers return, during which time they have to fend for themselves. The length of these foraging trips can be an indication of the mother’s foraging success – those that return earlier have found the food they need faster than those who are away for longer. Researchers at Marion Island regularly weigh fur seal pups throughout their suckling period. This growth monitoring, combined with oceanographic indicators, may shed some light into why these animals are so successful at Marion Island. Researchers are able to monitor where these animals are foraging by means of satellite relay data technology. We can determine what
While the seals of Marion Island rely on food from the sea, they form an important link in the food chain for yet another large mammalian predator being studied at Marion Island. Marion Island’s killer whale (Orcinus orca) population feeds on a wide range of prey species that haul out on the island to have their young. The killer whales have been seen hunting penguins, fur seals and even elephant seals. These versatile predators are capable of adapting their hunting strategies to the available prey. They may ambush penguins by hiding out of sight while a lone killer whale chases the penguins in the direction of the waiting pod. They also lay siege to seal colony beaches, waiting for elephant and fur seals to leave their beaches. These abundant food resources mean that killer whales are always around Marion Island in the summer. Individuals and family groups have been identified over years of research and intensive observations. It appears that the same individuals are present at Marion Island for large parts of the year. During winter the
A group of fur seals.
Image: Nico de Bruyn
Killer whales often come close to the Marion Island coastline and are readily seen by researchers in the field. They circle the island hunting seals and penguins. Image: Nico de Bruyn
whales leave the island, and satellite telemetry is used to determine where these animals go during the winter months. Field research Every year, as part of the annual overwintering team, a team of biologists braves gale force winds, ice pellet storms and torrential rains to monitor, weigh and observe southern elephant seals, fur seals and killer whales. A typical day for a seal researcher includes waking up as the sun rises, looking out of the window to check the weather, having breakfast, looking out of the window to check the weather, packing a backpack, pulling on gumboots and looking out of the window to check the weather. Eventually it is time to step out of the door – whatever the weather. On most days, researchers will walk along the Marion Island coastline checking every beach for southern elephant seals. Every elephant seal is then checked for a flipper tag and the colour and number are noted to identify individuals. This often involves traversing rocky beaches in bad weather, using rope ladders to climb down cliffs and wading through penguin colonies splattered with droppings in order to get to elephant seals. Once a month, seal researchers brave needle-sharp fur seal teeth while weighing 100 fur seal pups. The first weighing just after the pups are born is easy, with most pups weighing in at around 3 kg. Towards the end of the suckling period, the healthy, agile survivors weigh in at between 10 and 15 kg. As if sprinting over treacherous terrain in gumboots to catch pups is not
enough, researchers will have weighed over a ton of fur seal pups by the end of the day. Some researchers have also received nips from concerned fur seal mothers in recognition of their efforts on the beaches. Some southern elephant seals and fur seals have satellite transmitters fitted. But researchers have to wait for good weather before they can do this – something that does not happen very often. Satellite transmitters can only be deployed when the seals’ skins are dry. Southern elephant seals are immobilised using specialised drugs, which means that all researchers have to do a wildlife immobilisation course before going to the island. The drugs are given by means of a spinal needle, a length of drip tubing and a syringe. Only when the seal is immobilised does the deployment team approach the animal with the device and the epoxy resin. They then stick the device onto the seal while monitoring its breathing. They wait until the seal has recovered fully and is able to move independently. Catching a fur seal in a hoop net requires stealth and finesse. The scientist spots a fur seal mother from a distance while she is basking in the sun, goes into stealth mode, holding the hoop net at the ready for last 10 m of the ambush. The fur seal mother looks up, sees the scientist and runs away… attempt aborted! All the fur seals on the beach are now alerted to the intruder and some flee to the sea. The scientist now has to try at another beach. Eventually, after perhaps three or four attempts, the scientist manages to catch a fur seal mother unawares, deploys a transmitter, weighs her and releases her – and there are still five more transmitters that have
Researchers at Marion Island are often subjected to harsh environmental conditions, but the beauty of Marion Island remains constant and is appreciated by everyone who visits there. Image: Nico de Bruyn
to be deployed… The Marine Mammal Research Programme at Marion Island would not be in existence without the dedication and determination of researchers prepared to leave their families and homes in order to conduct research for 13 months on a remote island in the middle of the Southern Ocean. These dedicated scientists are responsible for collecting data that provide valuable insights in the biology of seals and killer whales in the Southern Ocean. Seal research on Marion Island is not for the faint hearted, but every scientist who has had the privilege to be involved with the programme will tell you that the rewards are endless – a real lifechanging experience. A beautiful sunset, an elephant seal giving birth, a fur seal porpoising through the water or watching killer whales resting for two hours almost within touching distance make it all worthwhile. ❑ Cheryl Tosh currently studies the foraging behaviour of Marion Island’s southern elephant seals. She spent 13 months on Marion Island as a seal researcher and is a post-doctoral fellow at the University of Pretoria. Prof. Marthán Bester heads up the Marion Island Marine Mammal Programme. His research is focused on the biology of marine mammals at Marion and Gough Islands.
Quest 9(1) 2013 39
The class of 2003 on board the old SA Agulhas with Isabelle Ansorg. A decade later UCT Oceanography honours students are still experiencing life at sea as part of their honours training. Image: UCT Oceanography
You can see the speed of the ship in this photograph – underway measurements. Image: UCT Oceanography
Life at sea Life at sea is very different from life on land... or is it? It may be hard to imagine spending weeks or even months at sea, but for many oceanography and marine biology researchers and students, living and working at sea is an important part of their careers. By Christopher Jacobs, Jennifer Butler, Mokete Kaogo, Alistair Blair and Marcel du Plessis.
M
The moon pool through which the CTD is lowered. Image: UCT Oceanography
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any students who start studying oceanography don’t quite know what they are signing up for. Oceanography is a multi-disciplinary and exciting science – an oceanographer can be a biologist, chemist, physicist, geologist, engineer, mathematician, computer scientist or a meteorologist. As a relatively new science, oceanography is a wonderfully challenging and exciting field of study providing many career opportunities. As part of the 2012 Oceanography Honours class at the University of Cape Town we were extremely fortunate to participate on the SA Agulhas II’s inaugural scientific voyage to the edge of the sea ice at 60˚S. At this latitude the new ship’s capabilities and facilities would be put to the test for the first time. The SA Agulhas II is currently the most advanced Southern Ocean research vessel in the world and it was a privilege to be on board her. The aim of our participation was to gain invaluable
hands-on experience in working with oceanographic instruments, understanding how data is analysed and interpreted, and most importantly getting a feel of what life as a seagoing oceanographer would be like. Why is ocean research important south of Africa? The oceans are linked to our survival on Earth and oceanographers work side by side with policy makers, social scientists, educators and businesses to develop effective ways of managing and maintaining our ocean resources. Our dependence on the global ocean will increase as we look to the ocean to sustain our expanding population’s needs such as food and water. Through continued research and new technology, we are learning how the oceans affect life and the future of our planet. To do this successfully, repeat monitoring lines need to be undertaken across all ocean basins. The GoodHope transect between Cape Town and Antarctica is one such line.
Q Careers
The CTD as it is lowered through the moon pool. Image: UCT Oceanography
Laboratory work can be repetitive, but is vital to certain types of research.
underway measurements (expendable bathythermographs (XBT) and underway conductivity, temperature, depth profilers (UCTD) were carried out when the ship was steaming, often at over 13 knots (24 km/h). The UCTD required three of us to stand outside on the back deck and drop a temperature and salinity probe over the side to a depth of 400 m and then winch it back. This often took about 20 minutes and in the big seas, especially at night, this often involved some heart-stopping moments leaning over the side of the ship with 8 m swells rocking the stern like a cradle. Other work that we had to do in our watch was to help with the running of the conductivity, temperature and depth profiler (CTD), which collects sea water at various sample depths. It was always exciting to see the CTD deployed through the ship’s moon pool. The moon pool looks like a chimney hole extending through the ship to the water. When it is opened the water rushes in and the CTD is lowered through it at 1 ms-1. It takes about 90 minutes for the CTD to be lowered to 2 000 m and then brought back up to the ship. Once the CTD is back on deck everyone rushes in to collect water samples for their research, which can be on the dissolved oxygen, nutrient, carbon dioxide or zooplankton concentrations in the top 2 000 m. The number of samples collected also provides us with an ideal opportunity to give a helping hand to the many scientists on board who need help with sampling, filtering and measuring water samples. A helping hand at sea is always appreciated, especially when the work starts to become repetitive. This kind of training allowed us to experience the vast array of science that occurs on the ship. ▲ ▲
The GoodHope programme was started in 2004 by the scientific community to answer the need for regular closely spaced oceanographic observations between Cape Town and Antarctica. The Southern Ocean plays a major role in the global ocean circulation and has a significant impact on present-day climate. However, our understanding of its complex three-dimensional dynamics and the impact of its variability on the climate system and affect of seasonality remain to this day rudimentary. GoodHope is an internationally recognised research line aimed at studying the impact that climate change is having on the oceans south of South Africa – changes in ocean temperatures, salinity, nutrients, dissolved oxygen and carbon dioxide concentrations are all being studied by scientists on board the SA Agulhas II. Achieving these lines allows the scientific community to gain a better understanding of the changes going on in the Southern Ocean and allows us the opportunity to compare summer and winter trends. The scientific aim of the cruise was to collect oceanographic and biological data in the Southern Ocean in winter. The oceans are very much like trees in that there is a difference in their biological productivity between seasons. Trees grow leaves in summer and lose their leaves in winter and so it is with the oceans. Productivity changes, but by how much? Combined with the need to test the new ice vessel in Southern Ocean conditions, the cruise presented a golden opportunity to extend the GoodHope line seasonally. To achieve the scientific aims, we had to complete a large number of underway and stationary deployments in each watch. The
Image: UCT Oceanography
The reality of working in an 8 m swell.
The ice at night.
Image: UCT Oceanography
Image: UCT Oceanography
There is always some time off.
Image: UCT Oceanography
Quest 9(1) 2013 41
At the ice!
The dining room and the bar.
Image: UCT Oceanography
Marcel and Christopher jamming with Luke Gregor. Image: UCT Oceanography
Life onboard What is life like on board the SA Agulhas II? One major difference between life on land and life at sea is that the ship is constantly moving, with water sloshing over the back decks in the large swells. In rough seas, we walked around like drunken sailors, holding onto every hand rail that we could find. This makes living and everyday actions extremely difficult – even frustrating! Everything has to be
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Image: UCT Oceanography
secured to stop it from flying around as the ship rolls. Chairs are often lashed to the desks, computers are tied down and special rubber mats have to be used on all the tables. Another difference is that the ship generally works 24/7 with everyone having to work a 12 hour shift, either during the day or at night. Scientists need to be awake at odd hours to deploy oceanographic instruments, collect samples and process them in the laboratory. Living on the SA Agulhas II, we simultaneously operate along two timelines. The first is the normal one. The days on the calendar change, the sun rises and sets, we eat meals at regular times and during the day the ship is a buzz of activity. Then there is the work timeline, the ship’s timeline, which is not defined by the changing of days but by the changing of watches and the time it takes to complete either a stationary CTD or UCTD. The boundaries between the days become meaningless and getting into the swing of life at sea takes time. At the start of the cruise, most of us needed time to adjust to the pitching and rolling of the ship and the queasiness that quickly crept in as soon as the ship left the harbour. Once the sea sickness subsides you start getting into the lifestyle at sea – and so work begins. Being part of the night shift (midnight to midday) involves changing your sleeping pattern, which can be a challenge for the first few days, but over time your body adjusts and you find yourself wide awake at 3 am. In between shifts and stations there was always time to read, play table tennis or watch a movie.
Getting hungry during your shift can become a bit of a problem if you are working at night. Meals are at set times on the ship and only leftovers, bread and cereals are available in the early hours. Having our honours course convenor Dr Isabelle Ansorge on board meant that we had an endless supply of chocolate and popcorn for many hungry evenings and early mornings. Food on board was excellent and there is plenty of it to go around. Meat seems to be the staple diet at sea. Every day we’d get the menu and plan our day around what meals we wanted to eat. The cold weather conditions, constant moving of the ship and long working hours means that you are always hungry and luckily with two options available for every meal no one is ever disappointed. There is also the added bonus of not having to do any dishes for the entire trip or paying for any meal – an ideal situation for any student. For those who are scared of putting on the kilograms, there is a gym on Deck 4. The ship is not all about work – outside of your watch you have 12 hours of free time. Normally you are exhausted from working in the cold or collecting and filtering water samples so you tend to go straight to bed for a few hours. Feeling awake? There is always someone looking for company. Playing the guitar and learning new songs was a popular source of entertainment, with some of the musicians (who are also scientists) often spending nights jamming together. There were also some very knowledgeable bird watchers on
Iceberg and through the ice.
Image: UCT Oceanography
board so it was always easy to grab a pair of binoculars and watch the beautiful albatrosses as they glided past the ship or even followed us along our voyage. Still bored? You can always disappear to the library or the Business Centre to check your emails and of course update your Facebook page. The ship is so modern and comfortable it feels like a real home away from home and you often forget you are in the wilds of the Southern Ocean. Best experience Getting to the ice edge and seeing how the ice changed from floating slush to pancake size and finally to ice floes was incredible. One of the main aims of this cruise was to test how the new ship would perform in the ice and also to see how fast she could break through it – according to Captain Gavin Syndercombe the SA Agulhas II managed to reach speeds of 13 knots. A highlight for everyone on the ship was seeing the different types of ice and icebergs. Although it was very cold (about -10 °C), we braved the weather and managed to capture a few pictures, even though we stood on an ice-covered deck in the freezing wind. The thrill of seeing an iceberg is completely unexplainable. Its size, colour and shape are absolutely beautiful and the sight of it is a once in a lifetime experience. Most people have to pay tourist companies US$1000s to experience such incredible scenery but as oceanography students we were getting this experience as part of our course.
On the return leg, we had time to work on our research projects but more importantly we had time to relax after 10 days of hard work. Going to sea is a great opportunity to explore places few people have visited. Having to travel through three different time zones in less than a month can be confusing and you can easily miss meals and be late or early for your watch. For most of us it was the first time we had been to sea and certainly the first time we had travelled as far south as 60°S. Life at sea is a big change from normal day life but it is part of a learning curve that improves and tests your independence as an individual. The work that we do may be tedious at times but it’s a fascinating work place. Everybody on board is united by a common purpose and it is that purpose that keeps us working, enables us to survive the discomforts and length of time away, and most importantly helps us all get along with each other so well. You learn a lot from all the different scientists on the ship and you get a good idea of the different types of opportunities in the oceanographic world. This was definitely an unforgettable experience, which all of us would happily recommend to learners eager to work in the marine sciences. Our time at sea and experience at the sea ice has contributed to one of the best learning experiences of our life. ❑ Christopher Jacobs, Jennifer Butler, Mokete Kaogo, Alistair Blair and Marcel du Plessis are all honours students in the Department of Oceanography at the University of Cape Town.
Definitions CTD: A CTD – an acronym for conductivity, temperature and depth – is the primary tool for determining the essential physical properties of sea water. It gives scientists a precise and comprehensive charting of the distribution and variation of water temperature, salinity, and density that helps us to understand how the oceans affect life. The CTD is made up of a set of small probes attached to a large metal rosette wheel. The rosette is lowered on a cable down to the seafloor and scientists observe the water properties in real time via a conducting cable connecting the CTD to a computer on the ship. A remotely operated device allows the water bottles to be closed selectively as the instrument ascends. A standard CTD cast, depending on water depth, requires two to five hours to collect a complete set of data. Water sampling is often done at specific depths so scientists can learn what the physical properties of the water column are at that particular place and time. A UCTD is a smaller version of a CTD but one that can be towed behind the ship at speeds up to 13 knots. XBT: XBTs – an acronym for expendable bathythermograph – have been used by oceanographers for many years to obtain information on the temperature structure of the upper layer (1 000 m) of the ocean. An XBT is a probe which is dropped from a ship and measures the temperature as it falls through the water. Two very small wires transmit the temperature data to the ship, where it is recorded in real time. The probe is designed to fall at a known rate, so that the depth of the probe can be inferred from the time since it was launched. By plotting temperature as a function of depth, the scientists can get a picture of the temperature profile of the water. An advantage of XBT deployments over CTD operations is that vessels do not need to slow down or stop, saving on ships’ time and cost. Container ships are now being used to deploy XBT probes along regular shipping routes, enabling scientists to not only collect data across wide ocean basins but to measure seasonal differences in the oceans’ top 1 000 m.
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On board the inaugural scientific voyage Dr Isabelle Ansorge found time to interview the Master of the SA Agulhas II, Captain Gavin Syndercombe about his life as a sea-farer.
The ship’s captain F
rom cruise liners to container vessels, all sea-going ships sail under the command of a captain, and perhaps the one person to aspire to is the current Master of the SA Agulhas II – 45-year-old Captain Gavin Syndercombe. The son of a Rear Admiral in the South African Navy, it is no surprise that he has chosen this career path given his distinguished family background. Where did you grow up? I grew up in Pretoria and Durban. At the time my father was in the navy and so we moved to Durban, where he was in command of the Strike Craft Squadron and then on to Pretoria, when he was promoted within the Defence Force. After matriculating in 1984, I went straight into National Service. Wanting to live at the coast I asked to be transferred to the navy and moved between Saldanha for basic training and Gordons Bay and Simons Town for my officer’s course. I ended up in Durban between 1985 and 1989. Coming from a seafaring background, with Rear Admiral Syndercombe as my father, it only seemed natural for me to follow in some of his footsteps. What are your main responsibilities as captain of a ship? My main responsibility as Master of the SA Agulhas II is to make sure that the ship and all the operations on board run safely and efficiently. My duties concern the stability of the
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ship, safe navigation, in particular through the sea ice and at all times when icebergs and growlers are present, loading and unloading both passengers and cargo, as well as ensuring that the ship’s personnel carry out their jobs. The SA Agulhas II is a brand-new vessel with stateof-the-art navigational instruments onboard. Making sure everyone understands how each system works and especially when the communications failure has been a challenge – a PhD in IT would certainly help! The key to doing my job successfully is excellent communications between the current Chief Mate Knowledge Bengu, Chief Engineer Alan Paterson, Bosun Lionel Alexander, Chief Purser Bernie Taillard, the Departmental Co-ordinating Officer Adriaan Dreyer and the ship-based Chief Scientist. With their help, I try to make sure that each science and logistics voyage is successful. A personal aspect to my job that I find extremely rewarding is helping the crew and young cadets advance in their careers to positions of greater responsibility on board. What skills are required? It is crucial that every captain has excellent communication, customer service, administrative and problemsolving skills. You must have the ability to deal with challenging conditions and be quick thinking to respond effectively to emergency situations at any time, day or night. Unlike deck officers, as the Captain I do not attend a watch system but I am on call 24 hours a day.
What are the differences between working for a commercial ship and a research vessel? The SA Agulhas II is an oceanographic research platform, so much of my time is spent working with scientists, planning their stations and advising them of changing conditions. On every cruise I meet a wide variety of interesting people from many institutes and universities. Being at sea on a research vessel allows you to observe marine life hands on, understand better the impact climate change is having on our oceans and to attend a wide variety of science lectures covering everything from ocean processes to invasive species inhabiting sub-Antarctic islands – an experience that would not happen on a commercial vessel. What events are the most challenging and what has been the most exciting experience? There have been times when weather conditions or equipment malfunction have resulted in research or logistic plans being cancelled or modified. This is frustrating for everyone on board, especially the scientists who have put years of work into their projects. Those are probably the most disappointing times – when we are unable to complete or have to shortcut our various missions. I have two most memorable occasions. One was the first time I saw the southern lights or Aurora Australis. We were just leaving the
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German Antarctic research base ‘Neumayer’ in March 2004, when suddenly eerie flickers of green and purple light flashed across the sky – the lights looked like ribbons dancing in the night sky – a surreal experience. It was the first time that I saw the Aurora Australis and I will never forget it. But the other experience that stands out the most for me was in 2007 when I was on board the SA Agulhas I as the second mate. A small yacht, the Cowrie Dancer, had capsized at 40˚S on her way to Australia. One of the sailors was missing and another had smashed his pelvis. As the only ship in close proximity we stopped all operations and headed to her rescue. Having spent years working on sailing vessels I was the most experienced person to go on board the Cowrie Dancer. Being dropped by helicopter into the ocean, swimming to the yacht to rescue the stricken crew and prepare the boat for scuppering was a daunting experience that I will never forget. It was a real macho-man moment and it has taught me to always respect the ocean.
Where did you study?
spent many years sailing and delivering yachts around the world – which, with my navy background, helped enormously in getting through my tickets quickly. Contact details for more information can be found through the South African Maritime Safety Authority (SAMSA) www.samsa.org.za
The most important foundation that you can give yourself is a proper schooling with a solid grounding in maths and physics. Maths and science is critical if you are to become competent in the general running of the ship – navigation skills certainly cannot be acquired without a good background in arithmetic. There are a number of tertiary institutes in South Africa, such as the Cape Peninsula University of Technology for Maritime Studies and Mechanical Engineering or the Durban Institute of Research and Technology, where you can study for a number of seagoing tickets such as Navigating or Engineering Officer. Once registered, aspiring cadets must complete a range of certificates and oral examinations in Maritime Studies which, with sea time, will take between five and seven years to complete for the position of Chief Deck or Engineering Officer. A further year of theory as well as ship’s time will allow you to qualify either as Master or Chief Engineer. I started my career with Smit Amandla in 2002 and joined the SA Agulhas as third mate in 2003. I had
What advice would you give to the next generation? Many students have a romantic view of life at sea, but days can be long and the work often hard and repetitive. Having said that, a seafarer’s life allows you to travel the world, meet interesting people and allows you to have a life outside of the standard 9 - 5 office rut. If you could change your career what else would you become? I have always wanted to work with the sea – so it would be natural for me to also have studied marine biology – despite spending half of my year in the Southern Ocean I like nothing more than relaxing under a palm tree anywhere in the tropics! ❑
A cadet on SA Agulhas II Cadet Mogamet Waleed ‘Wally’ Sedick talked to Gerda du Plessis, currently Chief Scientist on board Voyage 5 SA Agulhas II.
A
s part of Smit Amandla’s dedication to education they take on cadets to train and help them achieve their required ships time. One of these enthusiastic cadets is Mogamet Waly Sedick, a 23-year old from Grassy Park, Cape Town. He agreed to give us an insight into a cadet’s life and history. Tell us a bit about yourself and where you come from
What made you want to become a seaman and how did you get exposure to the field of maritime studies? I’ve always wanted to be at sea and originally wanted to sign up for the South African Navy. Then one day I went to a careers open day in Bellville as part of a school excursion. I ended up walking past a maritime studies expo. I watched the videos and the pictures of ships and wild oceans really impressed me and I thought ‘Aha, I can study seamanship it looks so exciting’. It was exactly what I had hoped to get involved in and from that day on I was hooked! I then signed up at the Cape Peninsula University of Technology (CPUT) and that was it. Obviously you can do the course work at the Durban Institute of Research and Technology but I wanted to stay close to my family and
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My name is Mogamet Waleed Sedick, but everyone calls me Wally. I grew up in Cape Town, and when I was
five or six we moved to Grassy Park, where I have lived ever since.
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friends and CPUT is the only technical university that allows you to register in Maritime Studies in the Western Cape. Are bursaries available and where would one apply? There are some bursaries available from CPUT, which are based on performance and merit – so you have to study hard and do well in your coursework! You definitely need to be good at maths and physics – the minimum grade to register is a C. What were the difficulties and successes you encountered in your studies and also in your career path? The travel from home to varsity is quite tiring and the exams are hard but the worst is having to complete our logbooks. We have a cadet training book with a set of tasks and duties, which we need to complete by the end of the cadetship. The cadetship ship’s time is 12 to 18 months, depending on who you train with and you have to complete all the tasks during that period. These tasks can range from course plotting, to watch duties, to cleaning the ship. After completing all these tasks you have an oral exam that determines if you get your class 3 ticket of competency or not. If I pass then I can sign up as class 3 deck officer.
What are your responsibilities and how much leave do you get? It depends on the company you work for. Deck officers normally spend four months at sea and then have one month off. As a cadet you are assigned to a chief navigation officer and you then spend the voyage under their wing. The hours are four on watch and then eight hours off every night and day – although you are never actually off, as quite often we have other duties that need to be completed within the eight hours.
bound. I also enjoy the ease of life at sea – not having to worry about cooking, paying for food, washing up – and I really can’t imagine doing anything else. Also once you qualify the money is good and as a deck officer you earn quite a big salary. But it is not the money that is important. If you were to change your career path what would you do instead? Do I have to? Probably an airline pilot if I had the money to train.
What are you likes and dislikes?
Advice for the next generation
A big dislike for me is the length of time away from home. Currently I am at sea for 76 days and as I’m a family man these long periods are hard for me. I am missing family, friends and birthdays. Another aspect is your position on board – I like to be in charge but when you are a cadet you effectively start at the bottom of the ladder, which you have to work yourself up. At this stage in my career I have no authority and have to do everything that the deck officer or captain tells me. So it takes a lot of discipline to get things right and keep everyone happy. But it’s worth it! I love being at sea and right now we are in the Antarctic and seeing the most beautiful sights – something that would never happen if I was desk
We are lucky because we have it easier than the previous generation of deck officers. In those days it was harder and there were fewer opportunities to get sea experience or bursaries to support your studies. With the new SA Agulhas II we can gain experience with the state-of-theart technology and because she is a research vessel we also experience working with marine scientists, which will really help me towards achieving my ticket. I believe that you must persevere with some area of study that you love and I couldn’t wish for a better career path. Contact details for more information can be found through the South African Maritime Safety Authority (SAMSA) www.samsa.org.za. ❑
The ship’s electrical engineer Albert Chipps is a 58-year-old electrical engineer working aboard the SA Agulhas II and was fortunate enough to spend the first three-month Antarctic voyage upon the vessel. We met up with him to pick his thoughts regarding the experience and what made him choose this extraordinary career path. Tell us a bit about yourself My name is Albert and I am the current ship’s electrical engineer. I grew up all over the place because my father was an electrician moving from job to job. We lived in Rhodesia which is now Zimbabwe, but also moved to Swaziland and then later I went to school in the Eastern Cape. I did my apprenticeship as an electrician straight after school and then went to
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sea. My first ship experience was on board the SA Van Der Stel, which I joined in November 1976. What made you interested in becoming a seaman? I’d always lived inland and my first experience of a ship was in Port Elizabeth when I was invited to have a look around an old British cargo vessel. It just gripped me from the moment I
saw it! I went on board and just knew I wanted to go to sea. I found out about Safmarine (South African Marine corporation) and I phoned them up, and as I had just qualified as an electrician it was easy to get a job. The rest is history and I am still here over 30 years later. How did you get information on your chosen career? My father was an electrician and after
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standard 8 (grade 10) he got me a job as an apprentice electrician, which I am extremely thankful for because that got me where I am today. What were your steps on your career path? I started off in the Safmarine fleet, moving from bulk carriers to general cargo vessels and I even worked on a ship carrying sugar from South Africa to Japan. For a number of years I was the chief electrician on a vessel carrying aluminium oxide from Australia to Durban before joining the large salvage tug vessels in 1981 – the one that everyone knows is the John Ross. I spent over 20 years working on salvage tugs sailing around the world doing long-distance towing and salvage operations. In 2001 I joined the French cable laying ship, the Chameral, which was responsible for maintaining the internet and telephone cables along the southern African coast. I spent 10 years on board her but unfortunately last year the ship caught fire off the Namibian coastline and we had to abandon ship. That’s how I ended up on the SA Agulhas II. Where did you study? I did my apprenticeship and started off in the coalmines in the Highveld and after I went to sea got a diploma in electrical engineering in 1979. This was at the old College for Advanced Technical Education in Port Elizabeth. But nowadays any good technikon such as CPUT will offer courses that will train you as an electrical engineer. How long did you study and what subjects did you need? A good grounding in both maths and science is very important and if you are good in those fields then understanding the technical aspects of my work are relatively easy. My apprenticeship took five years and my diploma another three years during my leave off the ship. What were the difficulties and successes through your career? I think the most difficult thing is to find a working environment that suits you. I resigned from my sea-going life in 1989 in order to spend more
time at home but it was only after I got back to working on ships that I realised how much I’d missed life at sea – a difficult realisation. What are your responsibilities and how much leave do you get? This is a unique voyage because it’s a brand-new ship that’s still on warranty, so we are trying to test as many things as possible before the warranty runs out. So a normal working day starts at 07:00 and stops around 17:00 but electrical problems happen all the time – so I am pretty much on call 24/7. What are your likes and dislikes One thing I just love doing is travelling and this lifestyle and job have afforded me the time to do just that. Who would have thought a year ago that I would be in Antarctic today? It’s given me the opportunity to travel the world – something I would not necessarily have been able to do in another career. I’ve also been fortunate to work on very specialised vessels like salvage tugs and now the SA Agulhas II, which is a research vessel. Different ships pose different electrical problems and so aspects of my job vary from ship to ship. I enjoy being part of the team and life at sea is easy. Of course you need to be a good team member and be able to work together easily. A 76-day voyage can get long and tiring and you need to be able to pull together as friends when problems occur.
If you were to change your career what would you do instead? The most important thing that’s happened to me is becoming a Christian 13 years ago and while I never really cared before, God opened my eyes to the plight of our Western Cape communities in particular and I have been very much involved in the lives of a group of disabled people in Bellville and 27 sexually abused and abandoned children in Khayalitsha, all of whom have become like family to me, so if I were to leave the sea I would probably get more involved in being part of a solution to many to the troubles I see in our communities. What is your advice for the next generation? That’s a crucial question because the problems facing the upcoming generation are way more difficult than during my time. I think what the next generation lacks more than anything are strong role models to guide them. They need people from my generation to start being much more open and transparent about what we believe and start working together and standing up for what we believe in. So thats what I want to do, to be a role model, like a huge signboard pointing them in the right direction. I would say to the next generation – listen to your conscience and never give up hope. In spite of what you might have been told or how you might have been treated in the past, every single one of you is unique and precious and have a crucial role to play in all of our lives that no one else in the world can do. ❑
Quest 9(1) 2013 47
At the ice.
Image: Joanna Thirsk
Dr Joanna Thirsk is a ship’s doctor and was on board the inaugural scientific voyage to the Southern Ocean. Joanna is currently working in Scotland – but yearns to go back to sea – maybe on the next voyage in April 2013.
The ship’s doctor What is your background? I’m 30 years old and grew up in Johannesburg, where I attended St. Mary’s School for Girls. I matriculated in 1999, after which I started studying at the University of Cape Town where I obtained my Bachelor of Medicine and Bachelor of Surgery degree (MBChB) in 2005. What made you interested in becoming a ship’s doctor? I have always loved to travel, which is the result of being the daughter of an airline pilot. In 2008 I became involved with the South African National Antarctic Programme (SANAP) when I was part of the 48th South African National Antarctic Expedition as the overwintering team doctor. This involved being ship’s doctor on the SA Agulhas on the way to Antarctica as well as on my return to South Africa more than a year later. I developed a passion for the ocean and life at sea and since then have had the privilege of being the doctor on board the SA Agulhas as well as her replacement, the SA Agulhas II, on many occasions. I am very lucky to have a job that I can use to explore the world.
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Can you give us some information on your career? My mother is a nursing sister so I had some exposure to the medical profession through her. I’m sure watching television medical programmes like ER and House has also had some influence! During my final year at school I would spend Friday evenings in the emergency unit of a busy hospital in Johannesburg to gain experience in the profession. I was also lucky to be at a school where they offered career advice and links to work-shadowing medical doctors. It is fairly easy to get information about a career as a doctor and most doctors are happy for interested school students to watch them and learn. Steps to your career path Apart from work-shadow experience, information about the medical degree programme is readily obtained from any university with a medical school. The application and selection process can be a bit more involved than it is for other degrees, requiring more evidence of commitment to a medical career, e.g. work experience, character references. Medical school is hard
work but very rewarding, especially once you start seeing patients and being allowed to carry out hands-on clinical work. After medical school you undertake two years of internship, during which you rotate through various specialties in designated hospitals. After internship you are required to do a year of community service. Both interns and community service officers are paid adequately and, contrary to popular belief, do have a choice as to where they work. Once those compulsory years are complete you can work independently in either the public or private sector and it is at this point that you can apply for specialist training in a field of your choice. To be a ship’s doctor you are not required to be a specialist but are required to do various courses so that you are able to handle emergencies in a ship-based environment where timely medical evacuation may be impossible and specialist treatment is not readily available. Keeping up to date with current medical practice is vital when on shore. Where do you study in South Africa? There are eight medical schools in
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the country associated with major universities such as Stellenbosch, University of Cape Town. During your years of study you will spend time both on the health sciences campus as well as in hospitals affiliated to the health sciences faculty where you are studying. Elective placements, rural work and community aid are also encouraged and provided for during your time at medical school. Can you get good bursaries? Bursaries are offered either by the university or other parties. Provincial health departments are the largest sources of funding for medical bursaries. If you show commitment to medicine and are getting good marks you are likely to receive funding for at least part of your degree, especially as you progress to the later years. Many universities offer funding based on matriculation results to attract good students. There is also a strong drive to help those from disadvantaged backgrounds succeed in their medical studies by offering funding. The university’s finance department will advise on what is available. How much time do you need to become a doctor and what subjects are crucial? Mathematics and science should be chosen as subjects at school and involvement in extra-curricular school activities will also increase your chances of being selected to medical school. Time spent as a student is usually 5 - 6 years. There are also post-graduate programmes available for those who have a degree, which then shortens the length of study time. Once you leave medical school you can be called a doctor although to practise independently one has to work in designated centres in the initial years. Difficulties and successes in study and career I have found medicine to be a very rewarding career choice. During the past seven years I have used my degree to travel and see the world and I have also obtained experience in many different fields which will stand me in good stead for the specialisation in emergency medicine which I intend
to make my career. I am currently doing an MSc in paediatric emergency medicine and also recently completed a year-long fellowship in intensive care research in the United Kingdom. Medical school was difficult because of the length of time spent studying without an income. Your university holiday time is also shorter than in other subjects, which is depressing but you get used to it. Being a doctor can be emotionally taxing at times and is very different to the glamour one gets exposed to on television. Daily responsibilities As a junior doctor you will work the hardest in your team and will have to cover nights and weekend shifts. There are so many branches of medicine that you can eventually choose to have a 9 - 5 lifestyle if you wish. Many specialties, however, require cover at all times and until you have finished your specialist training you will provide this cover after hours with consultant advice from home. As a woman with children one can apply to complete specialist training over a longer period. Leave will usually be about 20 - 30 working days a year as a junior doctor in the public sector, with an increased amount as a consultant depending on years spent in service. Being a ship’s doctor Crossing-the-line ceremonies happen on board vessels when newcomers cross the great lines of latitude for the first time such as the Equator or the Antarctic Circle. Nothing beats the feeling of crossing the Antarctic Circle and getting initiated by being repeatedly plunged into a bath of water that’s below freezing. What an invigorating experience but I now have a certificate to prove that I have crossed the line, so hopefully I will never have to be part of the ceremony again! I love being at sea – it’s a very special place and looking out of my window in the surgery while sailing past icebergs or seeing wandering albatrosses fly past is special … but then someone walks in with toothache and you have to all of a sudden be a dentist because you are thousands of miles from one. I have even had to stitch my own knee up after slipping on ice in Antarctica.
On board the SA Agulhas II.
Image: Joanna Thirsk
Likes and dislikes of working as a ships doctor Remote, wild places excite me. I like having the freedom to explore such regions. I like having a job where things are changing and dynamic – meeting new people and a life of constant learning. The SA Agulhas I and II have allowed me to interact with a wide range of scientists interested in the oceans, from mice on Marion Island to alien species surviving in Antarctica. If you could change your career path what would you become? I love animals so an easy step would be to become a veterinarian. Best advice you can give the next generation I would encourage women to enter into the field of science and scienceassociated careers. South Africa needs more women in these fields. Medicine is a fusion of science with the humanities so it is a great choice and if you ever have a chance to board a vessel – go for it! You will never regret that day. ❑
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The ship’s ocean technician Tammy Morris is the SA Agulhas II’s ocean technician. She tells us what this is all about.
Tell us a bit about yourself My name is Tammy Morris and I am going to tell you all a bit more about being an ocean technician. I was born in Benoni in 1980, but my family moved down to Cape Town when I was still very young. I grew up in Melkbosstand, along the West Coast, and always had a keen love for the ocean, spending many days on the rocks and the beach close to our home. I attended Van Riebeekstrand Primary School in Melkbosstrand and later Table View High School. I was always interested in biological and physical sciences and realising this from an early age, ensured that my subjects in matric (now Grade 12) included maths, science and biology so that I could study further in this career direction. Sadly, my subject levels in my final year at school did not allow me to obtain a matric exemption, and so academic universities were not an option for study. Initially I was keen to do analytical chemistry or biomedical technology at what was then known as the Cape Technikon, until the oceanography course caught my eye and I knew this was what I wanted to do. The Cape Technikon has been renamed the Cape Peninsula University of Technology (CPUT) and the course is currently being restructured and will be renamed Marine Science to fully incorporate all marine science disciplines. The entrance requirements for this course still are Grade 12 maths and physical science, with biology a recommendation.
provide students with a wide knowledge of marine science before specialising in the field they prefer. For me, that was physical oceanography. This revelation arrived one Saturday night when I found myself kneedeep in sardine and anchovy during a pelagic cruise in my experiential learning year. Fish, for me, smell and are not fun to work with! Instruments measuring the dynamics of the ocean environment were. The Marine Science course has a two-year theory section and a one-year practical, which requires the students to gain experience in the field in the disciplines they are keen on and write projects based on their work. If a student is industrious enough, they are normally able to take part in a few research cruises looking at different disciplines around the coast and getting involved in interesting things such as seal pup tagging and squid biology research. The first three courses earn you a degree in Marine Science. Thereafter the option is to continue on to do your BTech year, an equivalent Honours year of study where you will do coursework on more applied subjects such as Research Methodology, Applied Physical Oceanography, etc. You will also be expected to complete a thesis on a research topic and this is possibly the hardest year of all. The intensity of the work and assignments, along with a final thesis keeps you on your toes throughout the year. But it can be very rewarding. The bonus of taking a technical route in this field of work as opposed a strictly academic study, is that during your year of experiential learning of your first degree, you could land up in an internship or junior technician post which may lead to full-time employment later on. This is not always the case, but many technicians I have trained with in all types of disciplines (eco-toxicology, mariculture, etc.) have found full time employment quite early on their studies and thus can concentrate their BTech thesis on work taking place within their own teams. CPUT have gone on to offer an MTech degree in this field – a full dissertation style research project much the same as a Master’s degree.
What does the course entail? Where do you work? The course itself goes into first-year physics, chemistry and mathematics, all of which will have a distinct marine application – the basis of understanding for oceanographic principles taught at higher levels. The course allows the student to develop skills in physical and chemical oceanography, marine biology, eco-toxicology, marine ecology, marine law, instrumentation and technology and finally fisheries management. The aim is to
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I am employed by Bayworld Centre for Research and Education (BCRE), a section-21 non-profit research group established in 2004. Our team, based within the offices of the Department of Environmental Affairs, concentrates almost exclusively on Operational Oceanography and applying this knowledge to larger systems such as climate change and understanding
oceanographic processes. Our team deploy and maintain monitoring and specialised buoy systems to collect data on ocean currents, waves, temperature, etc. We also carry out surveys on board dedicated science cruises to investigate oceanographic features such as the mesoscale eddy field in the Mozambique Channel or the upwelling in Sodwana Bay and the implications to corals and the coelacanth. We also do physical oceanography support work for dedicated biological studies, such as the behaviour of squid during spawning seasons and the sardine run along the east coast of South Africa. A lot of work is ship based, but some takes place at field stations where we dive in our instruments using SCUBA and service them periodically. What are your responsibilities? I am the research and training coordinator for the team and as such I ensure that the team and students are able to get out there and do their work as easily as possible – responsibilities include financial administration and research funding proposal submissions. But my primary training was on the CTD systems and underway ADCP and I have used this and knowledge gained from mooring instrumentation and technology, to extend my own professional horizons to run my own research projects within the team. The experiences I have had over the last 12 years of being in the field and at sea, the places I have been to, the projects I have been involved with, have truly enriched my life. The hard part of this type of career is the time spent away from home and your social life can slow to a crawl. But the adventures and the experiences make up 100-fold and I would never choose a different path. It is certainly not easy, but the rewards are immense. My suggestion to anyone keen to take up this sort of career is to get involved with marine projects – start SCUBA diving, get involved with beach clean-ups and volunteer work to rehabilitate sick sea animals or at the aquarium, etc., do career shadowing at institutions or universities where marine science is offered and explore your options. Bursaries are available if you look hard enough and have good marks in high school, particularly in maths and physical science. With the development of new technologies in oceanographic instrumentation and satellite remote sensing and the increased public awareness of the oceans and climate change, physical oceanography and its investigators – both technical and academic – will become more in demand. ❑
Fo
c i d e M c i s n e r
who are you?
o F s t i W t a y g o l o h t a P & e n i c i d e Fo r e n s i c M The Division of Forensic Medicine and Pathology forms part of the School of Pathology in the Faculty of Health Sciences, University of the Witwatersrand. Forensic pathologists, forensic scientists and lab technologists make up the staff working in the Division of Forensic Medicine. The Division has responsibilities to perform autopsies as well as train medical students, paramedics and the police to name a few. Forensic Pathologist vs Forensic Scientist – what’s the difference? A “natural” death is defined as a death that results from natural disease processes and does not include trauma related deaths or deaths that have resulted from a hospital procedure. Forensic pathologists carry out autopsies on these cases of unnatural deaths. Forensic scientists perform a supportive role in the death investigation process. How do I become a forensic pathologist or a forensic scientist? To become a Forensic Pathologist, you must study medicine first. This 6 year long degree is followed by two years internship and then one years’ community service. You will then “specialise” in forensic medicine and pathology for a further five years and then become a “Specialist Forensic Pathologist”. A Forensic Scientist studies a Bachelor of Science OR Bachelor of Health Science degree at the undergraduate level. This is then followed by an Honours degree (one year), then a Masters (MSc) degree (two years) and then Doctoral (Ph.D) degree (3 years). Forensic Science Studies at Wits Forensic Science studies have not been possible in the past and the University of the Witwatersrand is the first University to introduce “forensic science” studies. The Division of Forensic Medicine and Pathology now offers a new one-year postgraduate Honours degree titled “Forensic Science”.
Upon successful completion of this Honours course, a “Bachelor of Health Sciences Honours (Forensic Science)” degree will be awarded. Students will then have the option to continue with further postgraduate studies in the Division of Forensic Medicine and Pathology, with Masters and PhD studies. The Honours course in “Forensic Science” aims to be a broadly based forensic sciences degree, where students will be exposed to different fields of forensic science and learn how they operate. Topics to be covered in the degree include: • Forensic Anthropology • Forensic Entomology • Investigative Psychology and Analysis • DNA and Molecular Techniques • Forensic Pathology (Brief overview) In addition to the above topics, a research methodology course will also be offered, so as to support students in their research-related activities. The Division is aspiring to stimulate and encourage research in the rapidly advancing fields of the forensic sciences and in doing so, is striving to become a research-active entity within the Faculty of Health Sciences. For more information contact the Student Enrolment Centre (SEnC) on (011) 717 1030 or admission.senc@wits.ac.za
www.wits.ac.za
Books Q Early astronomy Nicolas-Louis De La Caille – Astronomer and Geodesist. By IS Glass. (Oxford. Oxford University Press. 2013.) Nicolas-Louis De La Caille first set foot in Cape Town on 20 April 1751. He was one of the greatest astronomers of the 18th century. At the time, he was Professor of Mathematics at the Collège Mazarin in Paris and a member of the Royal Academy of Sciences. His aim was to measure the positions of objects in the southern sky. South Africa has a long history of astronomy and has the highest number of astronomers per head of population of any other country – quite an achievement for the southern tip of Africa. It is partly the actions of people like De La Caille that has placed astronomy on the map in this way. The significance of De La Caille’s aims in coming to Cape Town was that, more than any other astronomer of the time, he showed the value of making accurate observations. He was one of the first French ‘apostles’ of Newton – who was facing scepticism and hostility towards his theory of gravity – and had been for the past 50 years. De La Caille intended to provide scientific evidence to show that the movements of planets, moons and comets could only be interpreted in Newtonian terms. According to this excellent and comprehensive biography, De La Caille and his fellow mathematicians in Paris were the true successors of Newton when it came to the development of celestial mechanics and physics as a whole. Ian Glass is an astronomer at the South African Astronomical Observatory and Adjunct Professor at James Cook University. He has written not only an excellent scholarly account of De La Caille’s life, but an interesting and readable one. The book is one that can be read through in one sitting or picked up for interest over a period of time. He takes us through De La Caille’s introduction to Cape Town using the notes that the astronomer himself made about his journey. So the book not only provides interesting insights into how De La Caille made his observations and calculations, but also about life in the Cape in the mid 1700s. The approach to De La Caille’s life makes what could have been a dry account of a long-dead scientist into an exciting look at the way that scientific thought and theory were developing in the early days of mathematics, physics and astronomy. It also provides yet another fascinating glimpse of life in the Cape in the early days of colonisation. Tracking through Africa A Field Guide to the Tracks and Signs of Southern, Central and East Africa Wildlife (4th ed.). By Chris and Mathilde Swart. (Cape Town. Struik Nature. 2013.) Chris and Mathilde Swart are founders of the African-Arabian Wildlife Research Centre and have spent most of their adult lives working in biodiversity, surveying and research, as well as photography and film making. They are well known as African mammal authorities. The fourth edition of this field guide provides detailed coverage
52 Quest 9(1) 2013
of tracks, droppings, bird pellets, nests and shelters and feeding signs. Mammals are not the only group covered. The book provides information on birds, reptiles, insects and other inverebrates. It is known as the standard reference to the subject in the region. The fourth edition has beautiful full-colour photographs, along with examples of tracks and signs. Central Africa is fully covered, which was not the case in earlier editions of the book. One of the best features is a quick reference guide on the inside front and back covers, allowing the reader to skip quickly to sections on paws, hands and feet and mud nests, as examples. An indispensible companion for any naturalist or field biologist. Twitching Checklist of Birds in Southern Africa. By BirdLife South Africa and Sasol. (Cape Town. Struik Nature. 2013.) This little checklist is to be used in conjunction with Sasol Birds of Southern Africa (4th edition). It is a pocket-sized volume that provides a handy way of recording where or when you have seen bird species. There are six columns for multiple recording at six different locations. The list contains the latest names of all southern African birds and each species has its endemic and threat status listed. Essential for all twitchers. Tales in verse A Scarlet Tail. By Susan Long. Illustrated by Claire Norden. (Cape Town. Struik Nature. 2012.) This lovely children’s book is one of the series An Original African Tale and has stickers included at the back – an interactive book! Written in verse, the story is about an African Grey Parrot called Nebuchadnessar the Third and his playmate, Belinda the bee. These two friend travel through the rich jungles of Africa, happily practising acrobatics while watched by solemn and senior owls. The colourful stickers can be used in the book or could be used in a separate book as a way to help children write their own stories. The illustrations are lovely – and will appeal to children of all ages – as will the fresh approach to story telling. Wonderful bedtime reading!
Research that can change the world
Impact is at the core of the CSIR's mandate. In improving its research focus and ensuring that it achieves maximum impact in industry and society, the organisation has identified six research impact areas: Energy - with the focus on alternative and renewable energy. Health - with the aim of improving health care delivery and addressing the burden of disease. Natural Environment - with an emphasis on protecting our environment and natural resources. Built Environment - with a focus on improved infrastructure and creation of sustainable human settlements. • Defence and security - contributing to national efforts to build a safer country. • Industry - in support of an efficient, competitive and responsive economic infrastructure. • • • •
www.csir.co.za
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54 Quest 9(1) 2013
SCIENCE IS THE GLUE
e
THAT HOLDS EVERYTHING TOGETHER verywhere you look, you’ll see science hard at work, making society a better place in which to live. From the food you eat to the clothes you wear; from the battery in your cell phone to the mp3 files in your music player, it’s all about the science. South Africa needs more scientists if it is to compete on a global scale; people who are enthusiastic about finding solutions to today’s challenges and pushing the frontiers of the future. If you want to make a real difference, consider a career in science.
Bringing
science
and
learners
together
to
build
the
f u t u r e.
w w w. s a a s t a . a c . z a
Q Back page science
The Kraken supercomputer.
Image: NSF
The speedy Kraken The Kraken supercomputer at the University of Tennessee (UT) in the US, is one of the fastest in the world. In 2009, Kraken – the result of a $65 million grant to UT from the National Science Foundation – became only the fourth computer in history to perform more than 1 000 trillion calculations per second, known as a petaflop – so this is the only ‘flop’ around this computer – it’s no flop when it comes to making speedy calculations.
in the Department of Anatomical Sciences at SUNY Stony Brook, and his research team, while on a National Science Foundation (NSF)supported expedition to Madagascar. While on the expedition, Krause also found a group of fossil mammals known as gondwanatheres that have only been found elsewhere in South America and India. Based on this finding, Krause and colleagues came up with new theories about the plate tectonic history of the super-continent Gondwana, which comprised South America, Africa, Antarctica, India, and Australia, and Madagascar). Another of their findings is that dinosaurs could have been cannibals. Source: National Science Foundation
Flux ropes on the Sun
Source: National Science Foundation
Meet Madagascar's Majungasaurus The picture shows the reconstructed head of Majungasaurus crenatissimus, a 70-million-yearold meat-eating theropod dinosaur from the Late Cretaceous period that lived on the island of Madagascar. The skull is one of the best preserved and most complete dinosaur skulls ever found.
This is an image of magnetic loops on the sun, captured by NASA's Solar Dynamics Observatory (SDO). It has been processed to highlight the edges of each loop to make the structure clearer.
Institute for Telecommunications, Heinrich Hertz Institute (HHI) in Berlin are working on. ‘We are combining the new LTE mobile communication standard with the HEVC video compression standard, taking the best parts from both technologies,’ says Dr. Thomas Schierl, group manager at the HHI. Cell phone calls, websites and videos are currently transmitted using the UMTS standard. However, LTE, which stands for long-term evolution, is now replacing UMTS. Initially, LTE achieves speeds of 100 megabits a second. Future rollouts will see speeds rise all the way up to 300 megabits a second. By comparison, the maximum UMTS speed is 28 megabits a second. Not only do LTE networks transfer videos and other volumes of data faster, they also have shorter time lags. This is particularly important for video conferencing, where participants do not want to sit waiting for the response of their dialogue partner to be transmitted. To deliver videos to mobile devices at even greater speed, researchers are integrating LTE technology, which is fast in its own right, with the High Efficiency Video Coding (HEVC) video compression standard. Researchers at the HHI have developed important technologies for HEVC together with well-known electronics manufacturers. The advantage of HEVC is that the standard requires only half the bandwidth for high-quality video transmission, which means it can serve twice the number of devices as the previous H.264/MPEG-4 AVC standard. Source: Fraunhofer Gesellschaft
Image: NASA/Goddard Space Flight Centre/SDO
A series of loops such as this is known as a flux rope, and these lie at the heart of eruptions on the sun known as coronal mass ejections (CMEs.) This is the first time scientists were able to discern the timing of a flux rope's formation. Source: NASA
Faster video streaming The skeleton of Majungasaurus.
Image: Department of
Anatomical Sciences, Stony Brook University
The fossil skeleton of Majungasaurus was discovered in 1996 by David Krause, a professor
In the smartphones and tablet era, new types of data transfer are needed if networks are going to be able to cope with the onslaught of larger files, videos and so on. And this is exactly what researchers at the Fraunhofer
Combined with LTE functionalities HEVC enables faster video streaming. Image: Fraunhofer HHI.
MIND-BOGGLING MATHS PUZZLE FOR Q uest READERS Q uest Maths Puzzle no. 24
Win a prize!
Arrange twenty cubes in four piles using these clues: all piles contain an even number of cubes; there are twice as many cubes in the first pile as in the second pile; the largest number of cubes is in the first pile; all piles have a different number of cubes; each pile has at least one cube. How many cubes would be in Pile 1? Pile 2? Pile 3? Pile 4?
Send us your answer (fax, e-mail or snail-mail) together with your name and contact details by 15:00 on Friday, 7 June 2013. The first correct entry that we open will be the lucky winner. We’ll send you a cool Truly Scientific calculator! Mark your answer ‘Quest Maths Puzzle no. 23’ and send it to: Quest Maths Puzzle, Living Maths, P.O. Box 195, Bergvliet, 7864, Cape Town, South Africa. Fax: 0866 710 953. E-mail: livmath@iafrica.com. For more on Living Maths, phone (083) 308 3883 and visit www.livingmaths.com.
Answer to Maths Puzzle no. 23: Solution
Quest 9(1) 2013 57
UNIVERSITY OF THE WESTERN CAPE
Ever wanted to be a Forensic Scientist? A Dentist? A Pharmacist? A Psychologist? A Chartered Accountant? Or even a High Court Judge? However you see your future, if you’ve got ambition, ability and drive UWC is the place to be! UWC is home to 7 faculties: • • • • • • •
Economic and Management Sciences Dentistry Natural Sciences Law Community and Health Sciences Arts Education
Postgraduate research opportunities include but are not limited to: Pharmacology, Pharmaceutical Chemistry, Biotechnology, Bio-Informatics, Advanced Materials Chemistry, Nanotechnology, Ground Water Resource Development, Integrated Water Resource Management, Public Health, Museum and Heritage Studies, International Trade Law, Transnational Criminal Law, Orthodontics, Periodontics, Restorative Dentistry and Science & Mathematics Education.
All photographs are taken on campus with actual UWC students in their field.
SUBMIT YOUR APPLICATION FOR 2013 NOW! Online applications are available at www.uwc.ac.za For more information call us on 021 959 2451/3920, visit us at www.uwc.ac.za or connect with us on the Division for postgraduate studies via facebook at ‘DFPS UWC’