Green Space Our Place OUR VOLUNTEERS VOICE
Green Space Our Place
ISSUE 35 JUNE 2022
FRONT PAGE: Little Taccas volunteers (in red shirts from left) Bridget, Rosemarie and Jeannette.
BACK PAGE: You will find some interesting plants in the Botanic Gardens Conservatory including various Nepenthes.
C O N T E N T S
• From the Editor Page 2 • Little Taccas - Page 3 • Volunteer activities pictorial - Pages 4-9 • Beware the Stinging Tree - Pages 10-11 • Sculpture Botanica Cairns returns - Pages 12-13 • Catching up with Friends - Page 13 • Sugarworld Fruit Trees - Page 14 • Bird Tours need guides - Page 14 • Gardeneers raising funds for 30 years Page 15 • Tales from Mt Whitfield - Pages 16-17 • Introduced featheries Part 1 - Pages 18-19 • Feathered Friends Page 19 • Crane Flies - Page 20 • Did you know? - Page 20 • Cattana Capers - to weed or not to weed? Page 21 • The world beneath our feet - Part 8 Mites Page 22 • Striped Worms - Page 23
From the Editor Welcome
We have a jam-packed issue for you with seven pages of photos featuring our volunteers engaged in and enjoying the planned activities. We begin (next page) with a feature on the Little Taccas Children’s Nature Activities Program. Bridget, Rosemarie, Jeannette and Charles have been wonderful at supporting the delivery of our only kids activity in this program. It doesn’t take much to engage children in nature, but it does take time to prepare - a big thanks to our volunteers. I’d also like to thank our regular contributors (pictured right) to this publication and weekly email news. They volunteer their time behind the scenes to contribute over 750 hours per year, researching, writing and taking photos to support their articles an incredible effort!
Jennifer H Muir
And a thank you to those who assisted Sarah to promote the program at the EcoFiesta (see below two of the six who helped out).
The Friends of the Cairns Botanic Gardens have exciting news with the Sculpture Botanica being revived later this year (see pages 11-12). This event epitomises everything about the precinct, combining nature and artistic talents and attracting people from all walks of life to the Gardens including those who may not have visited before. Great work Friends!
Barry Muir
Janice Pichon
Louisa
Editor - Volunteers Supervisor, Louisa Grandy Proof readers - Michelle Walkden Volunteers Jennifer H. Muir, Sandy Long
Tom Collis
Contributors: Tom Collis, Janice Pichon, Dr David Rentz AM, Jennifer H. Muir, John Peter, Val Schier, Fran Lindsay, Geoff McClure, Barry Muir and Annabelle Symes. 2
Mary
Rosemarie
David Rentz
LITTLE TACCAS
Children’s Nature Activities Program
Bridget talking about butterflies.
Exploring the Botanic Gardens.
Rosemarie pointing out the pond critters.
Our award-winning Little Taccas program is about engaging children five and under in nature activities. With the support of volunteers, our Little Taccas program was created in 2014 to connect children and parents in nature activities and to promote the Botanic Gardens precinct. The program is simple but engaging with low-cost craft ideas such as creating a flower arrangement with floral foam, or making a caterpillar out of an egg carton. This is followed by nature exploration in the Botanic Gardens Conservatory or creek and storytime on the lawn (see front page) and always a little bit of natural play on a grassy slope.
Nature craft
Natural play
Little Taccas are always drawn to the pond and butterflies in the 3 Conservatory.
VOLUNTEER ACTIVITIES
Pat and Wendy
Una
Bernie
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Brigette
Maureen and Suellen
Down ‘n’ Dirty
Down ‘n’ Dirty volunteers have been in various locations around the Cairns Botanic Gardens and Tanks Art Centre precinct this year supporting the Gardens team with plenty of gardening and planting.
Anne
Joanne and Rhonnie
Bevin
Mel Jenny
Graeme and Sandy
VOLUNTEER ACTIVITIES Jabirus
Cattana Wetlands
Jamie with Jenny, Dawn and Elaine in the background
Dawn and Jabirus weeding Nuvua Sedge.
Jabiru volunteers have been busy working in various areas in the Cattana Wetlands: removing Sensitive Weed from the recently developed Sedge Swamp; clearing monocultures of Navua Sedge that had become established around Jabiru Lake; and are now working their way on to the peninsula to remove Centro vine and Guinea grass near the viewing platform. Their continued efforts have allowed more native plants to gain a foothold as well as improving the visual amenity of the Wetlands.
Martin
Jabirus weeding alongside Jabiru Lake.
A busy morning planned ahead. From left, Dave, Frank, Elaine, Sharyn, Dawn, Lyn, Prue and Mandy.
Jabirus know how to weed! Jenny, Julia and Elaine.
Sharyn planting along the banks of Jabiru Lake. 5
VOLUNTEER ACTIVITIES Tracks ‘n’ Trails
Rob, Brett, Hiromi and Russell installing prefab steps on the Yellow Arrow track.
Hiromi, Tracks ‘n’ Trails’ little powerhouse. The Tracks ‘n’ Trails group may be small but they make a huge impact keeping the Mt Whitfield Arrow Tracks safe for the many track users. They spend each Wednesday morning repairing steps or resurfacing tracks. Since July last year, they have installed / replaced 70 steps.
Hiromi and Rob using cold mix to infill timber steps on the Red Arrow track.
Volunteers are taught various methods to upgrade the tracks. These hand-made stone steps supporting the pre-fab steps, are a great addition to the Yellow Arrow track.
John, Rob, Russell and Hiromi completing stone work to support the pre-fab steps - close up above.
Hiromi, Rob and Russell installing new timber steps on the Red Arrow track. 6
VOLUNTEER ACTIVITIES Tour Guides
Have you been on tour within the Botanic Gardens precinct?
GSOP volunteers provide Heritage Tours each Thursday morning, leaving the Visitor Centre at 10am. Learn about the original use of the ‘Tanks’ and history of the Gardens. Or take a Flecker Garden Tour with a Friends of the Gardens’ member each week day, leaving from the Friends House at 10am. On Tuesday at 8.30am , you can join in on a bird Tour.
Heritage Tour: Trevor leading a group to Tank 5.
A great turn out for the Friends’ Garden Tour with Tom (left).
Bird Tour: Visitors being led by experienced birder, Graham Snell (second from right).
Stratford Nursery
Lyn
Rosi and Stratford Nursery horticulturalist, Ryan preparing a healthy morning tea.
Leslie The Stratford Nursery provides our volunteers with plenty of nursery experience in seed propagation and growing native plants. Volunteers are also able to learn plant names as they pot up and prune the seedlings.
Rosi and Tanya pruning seedlings.
Douglas and Mandy planting Black Bean seeds.
Mandy Rob among the tree seedlings. 7
VOLUNTEER ACTIVITIES Egrets
The Egrets have taken advantage of the rain over the past couple of months and continued to revegetate the area cleared of invasive species last year. The volunteers have replaced the monoculture of Guinea grass with native trees and vines that will attract flora and fauna to the Russell Street Environmental Park. The group has enjoyed the experience of watching the area evolve and grow.
Darryl, Patrick, Nathan, Jill, Brigette and Hiromi at the Russell Street revegetation site.
The Salties have spent over five years along the base of Mt Whitfield in Aeroglen, transforming the area from a weedy fire hazard to a native forest. Since July, they have planted over 700 plants and continue to maintain their revegetation sites. Keep an eye out for them on a Friday morning as you walk or pedal along the bike path.
Salties
Chris, Rob, Brett and Sue ready for planting. Rob, Sally and Sheila planting Alexandra Palms.
Douglas
Sandpipers On a Tuesday morning you will find the Sandpipers weeding and gardening along the Esplanade. There is always a cool breeze on those hot summer days, and once winter arrives, it is one of best places to be!
Jill, Jim and Chris enjoying a chat at morning tea with a gorgeous view. 8
VOLUNTEER ACTIVITIES The Green Space
Spot the volunteers at The Green Space busily working away in the Mandala Garden. The Green Space vegetable garden is attracting new faces each week especially as we enter the growing season. Volunteers have been preparing beds, planting seedlings and sowing seed directly into the newly composted beds. Helen and Jen planting kale seedlings.
Jodee planting seedlings. Campbell weeding.
Helen and Ian planting tomatoes.
Sugarworld Friends & volunteers
Botanic Gardens Curator Charles Clarke (right) met with the Sugarworld Friends & Volunteers group in May to discuss plans ahead.
Checking plants and labels, from left, Graeme, Janice, Wendy and Fran. 9
Beware the Stinging Tree
TOM COLLIS
Stinging Trees in the Wet Tropics
Stinging Tree or Gympie-Gympie, Dendrocnide moroides Atherton Tableland Stinger, Dendrocnide cordifolia Shiny-leaf Stinging Tree, Dendrocnide photinophylla There are three species of Stinging Tree in the Wet Tropics all belonging to the genus Dendrocnide. Although called ‘trees’ they are mostly small shrubs growing to about four metres with soft, light wood. In the rainforest, they prefer sunny places along the edges of streams and tracks, or sites where large trees have fallen. When land is cleared, Stinging Trees take advantage of the extra light and spread rapidly. While Rainforest Aboriginal people know their country intimately, early European settlers had none of this knowledge. They encountered many Stinging Trees in cleared areas and along tracks, resulting in multiple stings on themselves and their horses. It was quite hazardous. Several letters appeared in the Tinaroo Regional Herald, and in March 1887 one correspondent stated that “on the Cairns Road, the packer’s horses have to push through the stinging tree and vines and several horses have died recently from the effects.” In another letter, in May 1889, Mr John Irvine offered to clear Stinging Tree from roads near present day Yungaburra “owing to horses getting killed”. Whether the horses died solely from the sting is not clear, and since the effects of severe stings can last for weeks and even months, the animals would have suffered badly, rendering them useless to the owners, who may have euthanised them. Most people in North Queensland are aware of the very painful sting that results from a casual brush against any part of a stinging plant. While undertaking research on Stinging Tree on the Atherton Tableland, botanist Dr Marina Hurley described the sting as “the worst pain you can imagine, like being burnt with hot acid and electrocuted at the same time.” As well as an initial painful sting the pain can persist for months and recur on contact with hot or cold water. 10
Stinging Trees inflict their excruciating pain through fine silica-tipped hairs that cover most parts of the plant including the large heart-shaped leaves and stems. The needle-like hairs are hollow and contain a neurotoxin that is injected into the skin on contact with the plant. The fine hairs can remain under the skin for months resulting in ongoing pain and discomfort. Even dead leaves are capable of stinging as the neurotoxin is very stable and long lasting. Botanists have reported stings from decades-old pressed herbarium samples. A method of treatment used by medical professionals involves using ‘Elastoplast’ or ‘Waxeeze’ to remove the fine hairs, application of very dilute hydrochloric acid, and painkillers. Indigenous people in the rainforest treated the sting with crushed green tree ants that contain formic acid. The acid may break down the silica-tipped hairs and/or the toxin. Sap from the Cunjevoi plant was also used to relieve pain. Amazingly, there are several creatures in the rainforest that eat the leaves of Stinging Trees. Green Ringtail Possums have been recorded feeding on new leaves of plants towards the end of the dry season (Alan Gillanders pers. comm.). Red-legged Pademelon have also been observed consuming whole leaves of young plants. Despite the stinging hairs most leaves show evidence of insect activity, with large sections eaten out. The beautiful White Nymph Butterfly lays eggs on the underside of the leaves and the emerging caterpillars greedily chew their way through the leaves. While many insects eat the leaves others suck on the sap of the plant. The Stinging Tree, Dendrocnide moroides has redcoloured fruits that look like a wild raspberry. The fruit is edible, but eating it is a risky venture as the tiny stem has needles on it, and occasionally some stinging spines are found on the fruit itself. Definitely not recommended!
Green Ringtail Possum
Red-legged Pademelon
Close-up of the fine hairs on the stem of a Stinging Plant
Atherton Tableland Stinger, Dendrocnide cordifolia 11
Sculpture Botanica Cairns returns Sculpture Botanica Cairns will return to the Botanic Gardens this year. Building on the two events held in 2016 and 2018, the Friends of the Cairns Botanic Gardens will again partner with Saltwater Creek Basketry Group to work towards an exhibition in October. Ten commissioned artists, and participants from five workshops, will produce sculptural works made of predominantly natural materials. These will be displayed in various parts of the Gardens and form an art trail to be discovered by visitors. This is an exciting project with lots of collaboration and learning of new skills and creative ways to use the natural materials found in backyards and in the Gardens. The exhibition will surprise and delight visitors and encourage them to explore areas of the Gardens with which they may not be familiar. The first workshop, run by Wendy Sheils, will be held at the Botanic Gardens Visitor Centre on 25 June and bookings can be made through Trybooking.com. Further workshops will be held on 9 July, 20 August, 10 September and 24 September to coincide with the Basketry Group meetings. A photographic competition, also funded by the Friends, will be held in conjunction with the exhibition. 12
Catching up with Friends Val Schier
Annual General Meeting The AGM saw two new members elected to the committee: Friend’s member Annabelle Symes who volunteers her time with the Gardeneers, in the shop and providing garden tours; and a new member, William Martin, who will be the new publicity officer which has been so capably filled by Lorraine Smith for many years. A big thank you to Lorraine and also to Barry Muir who did not stand for re-election. William van Bakel has come back on board as Treasurer. Continuing in their roles are Megan Lilly, Jeannette Wehrle, Michael Hyde, Sue McCulloch, Jenn Muir and Peerapan Maslen (assistant to the Treasurer). Elaine Harrison has taken over Del van Mierlo’s position as vicepresident and David Rentz continues as patron. History of the Gardens talk at AGM There was much interest in the talk that President Val Schier delivered at the AGM in March. Most people do not realise that from the time it was first proposed in the 1880s, the Botanic Gardens precinct has supported many different activities such as a market garden, a zoo, aviaries, a railway line running through the eastern section, a cremation ground for Sikhs, a Herbarium, curators living on site in Friends’ House, a commercial nursery, World War 2 fuel storage tanks and the Council depot operating rubbish collection from where the nursery is now. Accessions register AGM meeting attendees were able to view an Accessions Register which was retrieved by a former curator when he believed it was in danger of being thrown out. It has come back into the possession of Council after nearly 40 years. Friends have funded the conservation of the register which has hand-written lists of seeds and plants collected and distributed commencing in 1888 when Fitzalan was operating his nursery and opening the area up to the general public. A facsimile will be made so that it can be handled by the general public and the precious old book will go on display once a suitable case has been acquired. Easter plant sale Seems that Cairns residents never tire of buying plants and the Easter sale went very well with many new residents coming for the first time along with our regulars. The next sale will be at Carnival on Collins on the first Sunday in September, followed by the third big sale of the year, the Christmas Plant Sale, planned for the first Sunday in December. The trolley sales are held each week on Wednesday mornings between 8.30 and 11am if you are looking for particular plants.
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Sugarword Fruit Trees Fran LinDSaY
Anacardiaceae Spondias cytherea Hog Plum
These beautiful trees at Sugarworld Gardens will bring some memories for those who are familiar with deciduous trees. They are planted in a group and provide a spectacular display. During the summer months they provide good shade along the pathway and food for the Sulphur Crested Cockatoo; do they really eat it or just nibble and discard? Some of our local young people are familiar with the fruit and eat it too. During winter months, the trees lose their leaves. There are two varieties at Sugarworld. The one pictured is the Spondias cythera and can grow up to 25m. The smaller variety, near the Council work shed, is the Spondias dulcis. This smaller tree is in fruit at the moment. When green the fruit is crisp and sub-acid. As the fruit ripens to a yellow colour, the flesh softens and the flavour changes. The fruit have a sweet to acid flavour and can be made into jams. The young leaves can be steamed and eaten as a vegetable.
Botanic Gardens Friends’ bird tours need guides Are you a resident birder who knows the local birds, and would like to be part of a relief team to take visitors on guided bird walks in the Cairns Botanic Gardens? The weekly Tuesday morning Guided Bird Walk has been part of Cairns Botanic Gardens Friends’ program for the past 17 years, and is popular with locals, and interstate and international visitors. Since the retirement of its two primary guides, this walk is in jeopardy. The current guide, Shane Kennedy, and the Cairns Botanic Gardens Friends, are concerned that the tours could eventually stop if it is left dependent on Shane’s availability alone. Can you help? We need volunteers with local bird knowledge. If you are interested, you will be provided with training to assist when Shane is not available. If you’re interested, please email: cairnsbirders@yahoo.com.au
BirD PhoToS: JenniFer h MUir 14
FRAN LINDSAY
Gardeneers, from left, Daniel Agar, Del Van Mierlo, James Sing, Annabelle Symes, Rod Garrett and Val Auld. Absent members: Norma Wright and Rae Garrett.
Gardeneers raising funds for over 30 years
AnnaBelle SYMeS
The Gardeneers is a small group of Friends of the Cairns Botanic Gardens that meets on a Wednesday morning to propagate plants for the weekly trolley sales and the three annual major plant sales. All plant material is sourced from the Botanic Gardens. The Gardeneers commenced in 1991 and over the years have raised many thousands of dollars. The last sale alone raised over $8000. The main priority for the raised funds is to buy plants for the Gardens, but funding is also spent on projects that enhance the Gardens. The choice and actual buying of the plants is done by the Gardens curator. Rare and exotic plants are very expensive but important for the plant collection. The sales are a highlight for many keen gardeners in Cairns and the surrounding communities. There are regular trolley sale customers who arrive early to see what is available each Wednesday and new customers who are excited to be able to buy plants that they’ve admired as they strolled through the gardens. At the three major plant sales people queue well before opening time just to be able to buy a special plant. The Gardeneers currently consist of eight Friends’ members and remains small due to the area made available in the propagating shed. Although a small group, the Gardeneers are big in their endeavours to raise money for the Gardens and attracting community members into the precinct.
Friends plant sales are always popular with locals and visitors.
Come along and see Del (back left) or Rae (front) at the Wednesday trolley sales.
Daniel selling Medinillas at the Easter Plant Sale. 15
Tales from Mount Whitfield - Part 2 Since the settlement of Cairns in 1876, Mount Whitfield has not always been the Instagrammable backdrop it is today. Decades of extractive and agricultural pursuits along with urban development are not the only human activities that have marked its mountainscape.
Bushfire menace
Burning hillsides on Mount Whitfield was a regular occurrence in the first half of the twentieth century. Often beginning on the Aeroglen side, they raced across the ridges and down the hillslopes, at times towards the Botanic Gardens, threatening the original nursery and caretaker’s house, as well as homes and crops on the foreslopes. These bushfires destroyed virgin forest as they travelled across the mountain, leaving barren patches. Repeated fires in the same area stalled revegetation and facilitated further fire incursion into the forest. In 1944 the North Queensland Naturalists’ Club worried that the loss of forest over the previous 20 years on Mount Whitfield would soon see it become the “Castle Hill” of Cairns! After fires, the wooded habitat was replaced by grass and low scrub. Guinea grass, introduced in Cairns in the 1930s, is a prolific grower and added to the fuel load for fires. Burnt areas also facilitated soil erosion and the invasion of nuisance species like Lantana. This invasive plant was already a concern in Edge Hill in the early decades of the 20th century because of its tendency to form dense thickets smothering the native vegetation. Bushfires became less of a problem in the second half of the 20th century when fire management practices were implemented. Faced with barren areas on Mount Whitfield, the public became increasingly aware of the need to halt the devasting impact of fire on their scenic hillslopes.
Tourism drawcard
The founding fathers of Cairns were quick to seize on the development potential of Mount Whitfield, not only for elevated residences, but as a tourism drawcard. Visitors were already coming to Cairns at the beginning of the 20th century to holiday in the area.
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Janice Pichon
Watching over Cairns
World War II saw an increase of activity on Mount Whitfield. It became the bodyguard for a naval fuel storage facility which was excavated into the southern hillside. Mount Whitfield offers commanding views of the city centre, airport and Coral Sea and was a perfect site for defending the port of Cairns when it became a frontline navy base for the Pacific fleet. An area above the Tanks was requisitioned to establish communication and observation posts. Communication lines were run to all the anti-aircraft positions in the surrounding hills and ridges. Lookout posts were established and manned by the Volunteer Defence Corps. Headquarters were set up at a hillside private home and servicemen lived in tents on the property. Today, a stone wall and footings on the Red Arrow trail are remnants of the World War II lookout site.
No country for cassowaries
The Whitfield area was once home to the Southern Cassowary. As the suburbs around Mount Whitfield developed, particularly on its lower slopes, life became fraught for this iconic big bird. Degradation and loss of natural habitat created food shortages, and attacks by domestic and feral animals saw population numbers dwindle. As Mount Whitfield became popular as a recreational walking site, encounters with cassowaries increased and the birds were often fed. In the 1990s, there were several reports in the local paper of frightening encounters with aggressive cassowaries on the Arrow trails. The rumour also circulated that running could be banned on the Red Arrow because the thumping noise of a runner’s footsteps mimicked the stamping feet of a rival. However, contrary to popular belief, jogging does not incite cassowaries to attack; rather being fed changes their behaviour and then they boldly solicit food from people. Rangers estimated in the mid-1990s that only three to seven adult birds remained on Mount Whitfield. The last cassowary known as “Blue Arrow” was killed by wandering dogs at the end of 1996.
As early as the 1920s, some pioneering Edge Hill residents were making walking tracks to the top of the ridges above Collins Avenue. Together with the Edge Hill Progress Association, civic leaders explored the tracks in the early 1930s with a view to creating a lookout for tourists. Fanciful ideas such as a road to the top, with a rest house at the bottom and a summit kiosk were entertained but never advanced.
Evidence of the cassowary’s rainforest gardening role can be drawn from the presence of mango trees on the upper slopes of Mount Whitfield. This species was introduced into Cairns in its early days as a food crop and would not have been planted so inaccessibly high. These trees are thought to have grown from seeds defaecated by cassowaries which can walk many kilometres in the time it takes for the intestinal transit of digested fruit.
Nonetheless, over the subsequent decades, the proximity of this rainforest to the city had turned it into a popular tourist stop for visitors, as well as picnicking locals. Today, the walking tracks have been formalised into the Arrow trails. Hundreds of people frequent the Red Arrow each day and it is considered by some as a rite of passage when arriving in Cairns.
Back to green
Times have changed on Mount Whitfield. With its cassowary population now extinct, you are more likely to be surprised by wild pigs on the Arrow trails. The farmers, quarriers and soldiers have long gone, replaced by walkers and runners who crowd the trails in peak recreational hours.
The discontinuation of activities which had disfigured the mountain, together with the protection conferred by its conservation park status have allowed the return of native vegetation. This recovery to a more natural state is also facilitated by proactive fire and trail management, and projects to revegetate and remove invasive species. Of course, in the future, it will always be vulnerable to natural events. These days, the interplay of nature and nurture has seen the forest recarpet the lower slopes of Edge Hill, Whitfield and Aeroglen, cradling the more elevated residences. Its green cloak is a reminder of why the early Cairns citizens thought of Mount Whitfield as “Cairns’ roof garden” and “the lungs of the city”! Acknowledgement: Thanks to Beryl and Alan Stanton for their input.
Wartime lookout atop Mount Whitfield. Australian War Memorial
Scorched face of south-eastern Mount Whitfield in 1991. www.qimagery.com.au © The State of Queensland 2012
Above: Mount Whitfield seen from the airport 1944; and Below: today. Australian War Memorial
Recovery on south-eastern face of Mount Whitfield in 2005. www.qimagery.com.au © The State of Queensland 2013 17
INTRODUCED FEATHERIES: Part 1
After Europeans settled in Australia, many wanted to make their new home as much like their ‘old’ home as possible. They hoped this would help them feel more comfortable in a country that was so different from the one they had left behind. Thus, over the years, many exotic plants and animals were introduced, that subsequently spread. Many introduced plants and animals thrived in their new habitat because there was less competition for them than in their original environment. The environment into which they were introduced, and spread, changed as a result and the introductions often outcompeted the existing species. Exotic doves and pigeons (doves are generally smaller than pigeons) were introduced for their familiar call and appearance; chickens, ducks and geese for food. Later, Laughing Kookaburras and Rainbow Lorikeets, native to eastern Australia, were introduced into Western Australia (WA) for their familiar call and/or appearance, but they have had a negative impact on WA’s native fauna. In Tropical North Queensland, several exotic birds have been introduced, or have spread here from introductions further south. They include Rock Dove; Spotted Dove; House Sparrow; Scaly-breasted Munia (aka Nutmeg Mannikin or Spice Finch); and Common Myna. Common Starling may be getting closer, and there are many introduced bird species in southern Australia that may spread further over time. Rock Dove, also known as Feral Pigeon, Homing Pigeon, Racing Pigeon and Rock Pigeon are all the same species: Columba livia. The genus name ‘Columba’ is Latin for pigeon or dove, and the species name ‘livia’ is from the Latin ‘livens’ meaning ‘bluish, ashen’, which refers to the basic blue-grey plumage of the body. Pictured (top right) is a typical, basic plumage Feral Pigeon that I photographed in Kalgoorlie WA (thus the reddish soil). Note the typical blue-grey plumage, glossy purple and green sheen on the neck, two black bars on the wings, and pink feet and toes. Rock Doves/Feral Pigeons are attractive birds that can also be in a variety of colours including browns, white, pied or reddish. Pictured (bottom right) is one of the brownish ones – ‘on the fence’ and on a mission at the Cairns foreshore 18
JENNIFER H MUIR
They originate from the wild rock pigeons of Europe, Middle East, North Africa and South Asia, where they prefer open agricultural areas. They spread because of their association with humans: in North Africa, the Egyptians domesticated the birds over 5,000 years ago. Today Rock Dove/Feral Pigeon populations are still closely associated with human settlement in many countries in the world. They’re commonly kept for racing or food, but are also feral (wild) and widespread across Australia except in the most arid country. They prefer urban and rural parks and buildings, crops along roads and railways, and coastal cliffs. Since they were first released in Australia in the 1870s, flocks of Rock Dove/Feral Pigeons have been a regular sight. Like their ancestors, today’s Rock Doves prefer nesting on cliffs and ledges, and have adapted well to ledges on the artificial cliff faces of buildings. They nest in large colonies when possible, and unfortunately their acidic corrosive droppings quickly deface building surfaces, roof spaces in which they breed, and other public places. The necessary resulting cleaning is expensive. Although mainly seed eaters, in urban areas they also feed on fallen fruits, and food scraps dumped by humans in streets and parks, and on food put out for poultry and other domestic animals. Feral Pigeon flocks are regularly added to by homing pigeons that get lost and join the wild flocks. These flocks dominate the urban landscape, agriculture and country towns due to the availability of food, fresh water and safe breeding sites. Outside major cities, the largest populations are probably in rural areas, especially wheat-growing areas of eastern and south-western Australia. The many barns and sheds in those regions provide nesting sites Rock Doves/Feral Pigeons live for three to four years in the wild and up to 16 years in captivity. They breed all year, with peak times July to February, and male courtship display is often seen. A mating pair will have three to four broods per year of one to two eggs each, which hatch in 18 days. The young leave the nest within 35 days. This is quite a high reproductive rate meaning they are an ‘R-selected’ species (like the House Mouse), ie a Rapid Breeding Species.
Why is their reproductive rate so high? First, their natural lifespan (in the wild) is short: limited lifespan means limited breeding time, so they breed rapidly. Second, such a short natural lifespan could suggest a high mortality rate in the wild: as they usually live in flocks, disease may spread through the flock quite quickly and kill many individuals.
Feathered Friends JOHN PETER BirdLife Australia
Rock Doves/Feral Pigeons are also common prey for predators including falcons (especially super-fast Peregrine Falcons that feed on them almost exclusively). The golden rule is safety in numbers and fast flight for escape: Rock Doves are usually in fairly large, fastflying flocks, rarely in small numbers unless the flock is new. Further, larger numbers of birds in close-flying flocks can be confusing for predators, making it difficult for them to catch one bird to eat, out of a mass of fast-flying birds. European Starlings (introduced into southern Australia) are well-known for this. In tight flocks, the birds fly fast and change direction rapidly in a large mass, thereby protecting most birds within that mass. Rock Doves/Feral Pigeons are known to carry diseases which can be passed on in droppings, or by contact with the birds. Diseases such as Psittacosis and Salmonella, as well as Aspergillus and Histoplasmosis (both of which can be fatal) can be transmitted to humans, and between feral, domestic and seabird populations. They introduce weeds from seeds in their droppings, and attract ticks, mites, cockroaches, mice and rats, some of which also carry diseases. People who keep Rock Doves/ Feral Pigeons, especially in large numbers, put themselves and their neighbours at risk from such diseases and vermin. Many of these kept birds are released daily, and spend the day loafing and trying to mate on building roofs.
ANDREW SILCOCKS
Striated Heron The intertidal mudflats at the Esplanade are famous the world over for the variety of migratory shorebirds they support. But lurking in the background, preferring to shun the limelight, is another of Cairns’ ‘birds of the mud’. It’s the humble Striated Heron, also known as the Mangrove Heron. With their drab plumage blending in with their muddy surrounds, and their habit of quietly skulking about at the edges of the mudflats and among the mangroves, Striated Herons are seldom noticed — yet they’re a constant presence. Fish and crabs are their main sources of food. This prey is located by carefully creeping across the mud or through the shallows, before being speared with a quick lunge of the bird’s dagger-like bill. But some Striated Herons have developed an ingenious method of catching fish — casting a piece of bread or other food into the water as a bait to attract small fish to within reach of its darting beak. And although they regularly forage during the day, they often don’t stop when the sun goes down! Because they’re seldom seen far from mangroves, it’s unsurprising that they build their nests among the branches of mangroves, well concealed and out of reach of the rising tides. Each nest, a loose platform of mangrove sticks, becomes home to three or four lightblue eggs in August or September. After the chicks hatch, they sometimes adopt a ‘bittern attitude’, pointing their bills skywards while stretching their necks upwards, at the slightest hint of danger. 19
Crane Flies
DR DAVID RENTZ AM
Nearly everyone has seen crane flies from time to time, in the house or out in the garden. They look like giant mosquitoes. Craneflies are members of the family Tipulidae, the most diverse family of flies in Australia. They range in size from small midge-like flies to some real giants with a wing span of 75mm. They prefer moist habitats and so are well represented in the northern tropics. The larvae live in damp soils often along water courses. Adults are often found along creeks dangling from perches during the day. Some are attracted to lights. A few species cause economic damage to crops like wheat because the larvae feed on the roots of the plants. Craneflies are an example of a generalised fly. On larger specimens you can easily see the modified hind pair of wings, called halteres. These are associated with balance. Remove one haltere and the cranefly cannot fly properly and will fall to the ground. Halteres are one of the defining characteristics of flies. Although craneflies have prominent mouthparts, some species may not feed at all, others may feed on nectar or pollen. Adults live for only a few days, relying on stored nutrients garnered when they were in the larval stage. Craneflies are nothing to fear. In some places in the US they are called “Mosquito hawks” because they appear as giant mozzies but, of course, they cannot bite.
White-footed Craneflies, probably the genus Trentepohlia, are common in rainforests and in the Cairns Botanic Gardens. In dim light, the flicking white legs are just about all you can see.
Craneflies are often found dangling, often utilising a single leg for this behaviour, minimising the amount of the insect on the surface area of a leaf or branch, therefore reducing the chance of capture by marauding predators. But one would think that dangling would expose it to bats and could easily be picked off in mid-air.
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Originally from Central and South America, Cane [Rhinella Originally from Toads Central and (previously Bufo) cane marina]toads were South America, released Qld canefields (Rhinella, intopreviously Bufo,in August fromreleased Hawaii. into marina)1935 were Queensland canefields in Authorities believed the Toads August 1935 from Hawaii. would control the Cane Beetle that Authorities believed the here toads was accidentally introduced with would theinCane that was the sugarcontrol cane, so 1937,Beetle 62,000 toadlets accidentally with sugar cane, so in were alsointroduced released into thethe wild. 1937, 62,000 toadlets were also released into the wild. But Cane Beetles live high in the sugar cane and But Cane Beetles live high in the sugar cane and cane Cane Toads aren’t good climbers. This compromised toads aren’t good climbers. This compromised their their affectiveness as a control once the Cane affectiveness as a control once the Cane Beetles were Beetles were beyond Toady reach. beyond toady reach. Toads rapidly, increasing numbersand and The The toads bredbred rapidly, increasing in in numbers progressively spreading into NSW and NT, then WA. progressively spreading into NSW and NT, then WA. 20
Holorusia conspicabilis. Note the modified second pair of wings, called halteres. The ball-like structure on the end of the stalk bears an internal gyroscope-like structure that aids in flight.
The halteres are modified hind wings and the bulbous tips carry internal balancing ‘organs’ associated with flight.
JENNIFER H. MUIR They ‘mushroomed’ into a large, invasive population reducing amphibian, and population mammal They ‘mushroomed’ intoreptile, a large,bird invasive numbers by feeding on reptile, them, or poisoning that reducing amphibian, bird andthose mammal tried to eat the Toads. Cane Toads’ shoulder glands numbers by feeding on them, or poisoning those that contain potent toxin- cane that can rapidly predators tried to eat the them toads have kill a potent toxin inthat theirtryshoulder glands. to eat the Toads. AllAlllife their eggs eggs(laid (laidinin lifestages stagesare are toxic, toxic, including including their strands and shiny shinyblack blacktadpoles tadpoles strandsrather ratherthan thanclumps) clumps)and (live (liveiningroups groupsrather ratherthan thanindependently). independently). Adults predators that that Adults are are powerful, powerful, effective predators negatively animal species species and and negatively impact impact on on many many animal much ort, has been been put putinto into mucheff eff ort,including including voluntary, voluntary, has removing removingthe thetoads Toadsfrom fromAustralia’s Australia’s environments. environments. Adult ed by by large large Adult cane Cane toads Toads are are easily easily identifi identified shoulder each eye. eye. shoulderglands glandsand andaabony bony ridge ridge above each
Cattana Capers: to weed or not to weed?
Geoff McClure
Weeds are the bane of gardeners and habitat regeneration projects. But there are subtle differences in their management depending on legislation and desired outcomes.
(Centrosema molle, origin: central America) and Sensitive weed (Mimosa pudica, origin: tropical America). None of these species are listed in the Biosecurity Act or CRC documents noted earlier.
In Queensland the Biosecurity Act 2014 may categorise weeds to protect our environment or agriculture, and states that managers have a general biosecurity obligation to ensure that ‘restricted invasive’ weeds do not spread. To complement the Act Cairns Regional Council has produced two documents relevant to weed management at Cattana – the Cattana Wetlands Management Plan 2016 and CRC’s Biosecurity Plan 2019-2024.
Para and Centro were deliberately intoduced to benefit the pastoral industry. Navua and Para are particularly invasive at Cattana and may dominate or smother native grasses and sedges, eventually forming monocultures which support lower diversity of flora and fauna and restrict natural regeneration. Their management is exacerbated in wetland environments because of restrictions on the use of chemicals, and by further introduction during floods.
There are two guiding principles of weed management – firstly, their removal should consider follow-up management (eg by mulching, revegetation) because after removal they will probably be replaced by other plants, and usually by weeds. This is because many weeds are expert ‘invaders’ of natural ecosystems, and many have seed-banks that are viable for several years. For example, the Biosecurity Act categorises Sicklepod (Senna spp.) and Hymenachne (Hymenachne amplexicaulis) as invasive, with seed-banks remaining viable for up to 10 and 8 years respectively. Both occur occasionaly at Cattana, but after removal the site needs monitoring for the duration of the seed bank. This can be a very expensive exercise.
Some species have a low priority for removal by their impact and legislation. For example, Guinea Grass (Megathyrsus maximus), introduced from Africa in the early 1900s for livestock, is not a prohibited or restricted invasive plant under the Biosecurity Act. It is considered as beneficial to birds and insects at Cattana, restricts the spread of weeds mentioned above, and is often left in situ unless it proliferates.
Unlike domestic gardens, it is not possible to remove all weeds in regeneration projects, so a second principle is to prioritise species for removal according to their impact. At Cattana the most invasive species are Navua sedge (Cyperus aromaticus, origin: tropical Africa, first recorded in Cairns and Atherton in 1979), Para grass, (Urochloa mutica, origin: tropical Africa), Centro vine
Another example is Praxelis (Praxelis clematidea, origin: South America), first recorded near Tully in 1993. Praxelis is not a restricted invasive plant, and is not perceived as a threat at Cattana. In some repects it is beneficial - note two photos below by Andew Krumins of the native Speckled Line-blue (Catopyrops florinda estrella) and Swamp Tiger (Danaus affinus) butterflies feeding on nectar at Cattana Wetlands. Other insects either feed or pollinate Praxelis, and in this context it is considered beneficial to birds. Many other weeds perform similar functions (eg Blue snakeweed (Stachytarpheta urticifolia). So the question of whether to weed or not to weed involves lots of issues. Speckled Line-blue butterfly
Swamp Tiger, Danaus affinus
Andrew Krumins
Andrew Krumins 21
THE WORLD BENEATH OUR FEET: Part 8 - Mites Mites are tiny, almost invisible, and apart from those that are of economic concern to humans, little studied. The majority are beneficial, living in the soil, leaf-litter and mulch and assisting in the decay of organic material by consuming bacteria, fungi, plant or animal matter.
BARRY MUIR
A typical Oribatid mite with a few water drops on its back. From “All about Mites - a Chaos of Delight”.
Some species live in water, others live on plants, others in hot springs or caves, while others again are predators or parasites, such as Varroa, a parasite of honey bees, and the scabies mite of human children and the cause of mange in dogs. House dust mites, found in warm and humid places such as beds, can cause several forms of dermatitis or asthma. It's estimated that each adult human might be supporting over a million follicle mites, with a little colony of mites able to live in the base of a single hair follicle. Mites have no anus, so instead of excreting they eventually explode and die in a tiny shower of faeces! Mites that terrorise plants include the so-called Spider Mites that can damage orchids, Velvet Mites (big mites, up to a millimetre, that live on moss), and Gall Mites that cause lumps on leaves. Nearly 50,000 species of mites have been described but there may be a million or more species still to be studied. Curiously, the tropical species Archegozetes longisetosus is one of the strongest animals in the world, relative to its mass (100 microgram): it lifts up to 1,182 times its own body weight, over five times more than would be expected of such a minute animal. This equates to a 100kg human lifting about 118 tonnes. A mite also holds the world speed record for its size. Paratarsotomus macropalpis is the fastest animal on Earth; at 0.7mm long, it can run at 322 body lengths per second, that's 0.225 metres per second. An equivalent cheetah would need to be running at 2052km/h! Mites are distantly related to spiders and most are from one-quarter of a millimetre to three-quarters of a millimetre in length, so they are easy to miss. Mites don't have heads - they have a structure called a gnathsoma which supports the mouth and feeding parts. Any brain, or eyes, if present, are in, or on, the body-like structure behind it. The sexes are separate in mites. In some species the male deposits a sperm packet which is then picked up by the female. Some mites give birth to living young, in other species eggs are laid wherever the mite happens to live. They take up to six weeks to hatch, according to species, and the first stage larvae have six legs. After three moults, the larvae become nymphs, with eight legs, and after a further three moults, they become adults. The main group of mites we are interested in here are those that live in “The World Beneath Our Feet” - the Oribatid mites - very common in leaf litter and soil and important indicators of soil health. 22
Most Oribatids have no impact on gardeners apart from
improving the soil. Potting soil mites, for example, make their home, together with many family members who don’t practice social distancing, in flower pots. These tiny creatures are about the size of a pinpoint and are very easy to miss. They may appear as little white dots walking over the surface of the soil or along the edge of a plant container. The Oribatid mite is commonly found in gardens and wooded areas and occasionally make their way to patios, decks, container plants or even inside homes. Slower moving soil mites are also found in compost. You may recognise some of these as shiny round mites that move extremely slowly and look like tiny mobile eggs. These mites generally feed on fruits and vegetables, including rotting fruit rinds. If you are concerned that these mites are competing with your compost worms (which they are not – the worms eat them), you can place a piece of watermelon rind in your compost pile and remove it in a few days, hopefully with a large number of mites attached, which you can then study. If you are dead-set on getting rid of them in your planting containers (you should ask yourself why you would want to remove these largely harmless or beneficial critters), you can simply remove your plant from the pot, soak it to remove soil and repot with new sterilized soil. In most cases, however, this is a waste of time because, if even a few mites survive, it won’t be long before nature takes its course and there is again the patter of (very) tiny feet.
A flower pot mite. Encyclopedia Brittanica
Striped worm
DR DAVID RENTZ AM
This striped worm is one of a number of Bi-coloured Flatworms. Terrestrial flatworms (also called land planaria, Phylum Platyhelminthes) live in land in damp, dark places and leave a silvery mucus trail like a snail. They hunt on wet nights for prey such as earthworms, small insects, slugs and snails. They are not regarded as a threat to humans or pets. Flatworms have an interesting way of eating. Most use a sticky trail and long body to trap prey. They then evert a feeding tube (pharynx) through the mouth, usually located half way along the body. Juices from the tube contain enzymes that break the tissues of the victim into smaller particles. Small hair-like structures in the tube then sweep the food particles into the gut of the flatworm.
Membership details email - phone 4032 3900 or email info@botanicfriendscairns.org.au After joining you can support the Friends in many ways; as a committee member, in the Friends Shop, as a tour guide or assisting with events.
Friends of Sugarworld Botanic Gardens Contact Fran Lindsay frantastic10@bigpond.com
Newsletter Contributions: Please submit articles (must be volunteer or nature based) by first week of August for the next quarterly publication in September. Email: l.grandy@cairns.qld.gov.au Please note articles are subject to editing.
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Flatworms are a very diverse group and occur in marine and freshwater environments as well as on land. The terrestrial flatworms are free living, but many flatworms, such as tapeworms, are parasitic. At least one has been used in the biological control of the Giant African Snail in the Pacific Islands.
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Terrestrial flatworms are hermaphroditic and each individual possesses both male and female reproductive organs. They are also capable of an unusual form of reproduction called fragmentation. The worm divides itself into two portions and then both parts just crawl away from each other to develop into ‘new’ worms. There is some truth to the observation that you can cut a flatworm into several pieces and almost all the bits can develop into fully functional flatworms.
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Mondays - Russell St Environmental Park Egrets 9am-noon Tuesdays - Cattana Wetlands Jabirus 9am-noon Tuesdays - City Sandpipers, Tuesdays 9am-noon Wednesdays - Botanic Gardens Down ’n’ Dirty volunteers 9am-noon Wednesdays - Tracks ‘n’ Trails 9am-noon Thursdays - Stratford Nursery 9am-noon Thursday (once a month) - Sugarworld Gardeners & Friends Fridays - Saltwater Creek ‘Salties’ 9am-noon Fortnightly Thursdays - Children’s Nature Activities Program - Little Taccas Visitor Enhancement Volunteers - rostered hours to suit individual Heritage Tour Guides - Thursday 10am
Interested in becoming involved with your local park, reserve or tracks in your community? Contact us to register as a Council volunteer and be involved in beautifying your park (enhance planting, weed management, litter clean-up), reporting on issues (graffiti and vandalism, anti-social behaviour, maintenance issues) and building community participation (networking activities) with Council support. If you are interested in supporting any of our weekly groups or volunteering in your local area contact Volunteers Supervisor Louisa Grandy 4032 6648 or email greenspaceourplace@cairns.qld.gov.au 23
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