KIMBERLEY CETACEAN SURVEY
2009 Observations on the distribution and behaviour of humpback whales and other cetaceans in Kimberley waters
KIMBERLEY WHALE WATCHING
Kimberley Whale Watching - Kimberley Cetacean Survey 2009
Kimberley Whale Watching - Kimberley Cetacean Survey 2009
Richard Costin & Annabelle Sandes KIMBERLEY WHALE WATCHING PO BOX 7139 Broome WA 6725 Kimberleywhales@bigpond.com
www.kimberleywhales.com.au
Cover: Humpback whale cow and calf, Cable Beach. Š Annabelle Sandes / Kimberley Whale Watching - August 2009
Images available from Kimberley Media website www.kimberleymedia.com.au
All images Š Annabelle Sandes and Richard Costin / Kimberley Whale Watching / Kimberley Media 2009
Kimberley Whale Watching - Kimberley Cetacean Survey 2009
The Kimberley coast is one of the most complex and mysterious marine environments in the world. This is an area of amazing diversity that is linked by the currents and tides that sweep along the coast and through the islands and reefs of the Bonaparte and Buccaneer Archipelagoes.
Kimberley Whale Watching - Kimberley Cetacean Survey 2009
Dugong Bay
There are more than 2815 charted islands and reefs, and 13,000 km of coastline that stretches from Broome in the South, to Wyndham in the North. The area has recently been recognized as one of the most significant coral reef provinces in the world. Almost every island is fringed by its own reef that is home to many undiscovered and unknown species. The Kimberley coast is a shallow marine environment that has experienced massive fluctuations in sea levels over the past 350 million years. A record of some of the earliest coral species on the planet is preserved in the Devonian reefs of the Napier and Oscar Ranges. The “modern� coral species of the Kimberley are thought to have evolved over the past
Turtle Reef
20,000,000 years. During the last ice age, between 10 and 20,000 years ago, sea levels are thought to have been 150m below their present level. Rapid melting commenced approximately 18,000 years ago with sea levels around Australia stabilizing approximately 6,500 years ago. The islands, reefs and bays were again colonized by corals , filter feeders, sponge gardens and sea grasses. This unique environment is now home to many fish species, and marine mammals, such as the Humpback Whale. The Kimberley Humpback Whales mate, rest and feed in the shallow, secluded inshore coastal waters from Broome to Kalumbaru. Nearly hunted to extinction by commercial whalers from 1806 to 1980, by 1985 the west coast
Sandbank, Willie Creek
population was estimated at no more than 500 individuals. In recent times this population of Humpbacks has experienced a remarkable recovery and is now estimated at between 16,000 and 22,000 whales. Early research in the 1990s indicated that the main concentration of whales occurred between Camden Sound in
Corals and anemones, Turtle Reef
the Buccaneer Archipelago and Pender Bay on the Dampier Peninsular. The main focus of research in the past has been limited to the Camden Sound and Pender Bay areas. This has left huge gaps in our knowledge and understanding of how the whales are using other areas along the Kimberley coast. As the population increases, their range will extend along the Kimberley coast. The expansion of the oil and gas industry on the Kimberley coast in the last few years has highlighted the need for more comprehensive studies of the Kimberley marine environment. The 2009 Kimberley Whale Watching Survey has attempted to compare the relative concentration of whales between Broome and Camden Sound. A new picture has evolved which indicates the importance of the Kimberley coast to this recovering population of Humpback Whales. The Breeding Group D population is now thought to be the largest single population of Humpbacks in the world. The whales and their habitat should be regarded as one of Austalia’s national treasures.
Their continued recovery and survival will depend on providing an adequate level of protection and management for the whales’ calving grounds in the Kimberley and their main feeding grounds in the Antarctic.
Recognised milling, resting and calving areas. Huge gaps still exist in our knowledge.
Humpbacks Worldwide Humpbacks are a cosmopolitan species found in all of the world’s oceans, with all but one population migrating between tropical waters to mate and calve, and productive colder waters to feed. There are now considered to 7 be populations south of the equator, the wintering grounds as follows:
G (southeast Pacific): Ecuador, Galpagos, Colombia, Panama and Costa Rica Humpbacks are abundant throughout the Antarctic in summer, South to the ice edge, but not within the pack ice zone. Worldwide, most populations are migratory, but there appears to be a
resident and non-migratory population in the Arabian Sea, which is genetically distinct from that in the Southern Indian Ocean. Sub-groups within a population are known as ‘stocks’, and although there does not appear to be much cross equator migration, (although Breeding Group G may venture into the Northern hemisphere in winter), matrilineal DNA suggests that at some
Breeding Group A (Southwest Atlantic): coast of Brazil B (Southeast Atlantic): the coast of West Africa from the Gulf of Guinea down to South Africa C (Southwestern Indian Ocean): coasts of eastern South Africa, Mozambique, Madagascar (Southern, western and eastern coasts), Mayotte, the Comoros and other western Indian Ocean island groups; D (Southeastern Indian Ocean): northwestern Australia E (Southwest Pacific) northeastern Australia, New Caledonia, Tonga and Fiji. F (central South Pacific): Cook Islands and French Polynesia Nine whales off Willie Creek - 30 August 2009
time in the distant past, there may have been some cross equator interbreeding. Countries with native populations, according to the IUCN Red Book are;
Spain; Sri Lanka; Taiwan, Province of China; Tanzania, United Republic of; Timor- Leste; Togo; Tonga; Trinidad and Tobago; Tunisia; Turks and Caicos Islands; Tuvalu; United Arab Emirates; United Kingdom; United States; Uruguay; Vanuatu; Venezuela; Vietnam;
Virgin Islands, British; Virgin Islands, U.S.; Wallis and Futuna; Western Sahara; Yemen
American Samoa; Angola; Anguilla; Antigua and Barbuda; Argentina; Aruba; Australia; Bahamas; Bangladesh; Barbados; Benin; Bermuda; Brazil; Cameroon; Canada; Cape Verde; Cayman Islands; Chile; Cocos (Keeling) Islands; Colombia; Comoros; Congo; Congo, The Democratic Republic of the; Cook Islands; Costa Rica; Cuba; C么te d'Ivoire; Denmark; Djibouti; Dominica; Dominican Republic; Ecuador; El Salvador; Equatorial Guinea; Falkland Islands (Malvinas); Faroe Islands; Fiji; France; French Polynesia; French Southern Territories (the); Gabon; Gambia; Ghana; Greenland; Grenada; Guadeloupe; Guam; Guatemala; Haiti; Honduras; Iceland; India; Indonesia; Iran, Islamic Republic of; Ireland; Jamaica; Japan; Kenya; Kiribati; Korea, Democratic People's Republic of; Korea, Republic of; Madagascar; Malaysia; Maldives; Marshall Islands; Martinique; Mauritania; Mauritius; Mexico; Morocco; Mozambique;
Whale breaching off Cable Beach - 30 August 2009
Kimberley Cetaceans Humpback whales (Megaptera novaeangliae) come to the tropical waters of the Kimberley to mate and give birth. Once nearly hunted to extinction with less than 600 individuals in the West Coast population at the cessation of whaling, latest IWC estimates place the Breeding Group D population at 22,000 individuals (+/- 8,000), making BGD the largest humpback population in the world. Humpbacks are rorqual whales, sifting krill and small baitfish through keratin plates called baleen. Although the bulk of their feeding takes place in the Antarctic during the Summer months, Kimberley Whale Watching has observed feeding behaviour in Kimberley waters. Dugong (Dugon dugon) are classified as vulnerable to extinction under the 2006 IUCN Red List of Threatened Species. Australia supports the largest remaining dugong population in the world. Dugong are found along the Kimberley coast, with significant pods observed at the southern end of Roebuck Bay in the seagrass meadows.
The Australian Snubfin dolphin (Orcaella heinsohni) is thought to be a resident in shallow seagrass beds in and adjacent to the North-West Marine Bioregion. Snub-fins are shy animals, and can dive for up to 12 minutes when threatened. Kimberley Whale Watching observed Snub-fins h this year in Camden Sound, Yampi Sound, the Prince Regent River and the Buccaneer Archipelago.
Kimberley Cetaceans Pygmy Killer Whales (Feresa attenuata), average size 2.1 - 2.6m are little known animals, rarely seen in the wild though widely distributed. Inhabit tropical waters 18°c or warmer, and are usually seen in pods of less than 50 individuals. Kimberley Whale Watching sighted a pod of approximately 20 Pygmy Killer Whales off Willie Creek on the 24th of July 2009.
Bottlenose Dolphins (Tursiops trucatus) vary greatly in size and colour. There appear to be two distinct varieties, inshore and offshore. The smaller inshore types are often territorial, the larger oceanic dolphins nomadic. The dolphins at right were sighted in 2006 and 2008 in Camden Sound. Often found in the company of other cetaceans; Bottlenosed Dolphins in the Kimberley have been observed with Pilot Whales and Humpback Whales. Bottlenose Dolphins are common in the Kimberley.
Long Snouted Spinner Dolphins (Stenella longirostris) are one of the most acrobatic of all cetaceans and are found in large pods of several hundred. Spinners often associate with other cetaceans. The pod of fifty, at right, was seen in Collier Bay in July 2009.
© Annabelle Sandes - Kimberley Whale Watching 2009
2009 WHALE SURVEYS 2009 has been a great year for cetaceans along the Kimberley coast. The first whales were sighted 20 nautical miles west of Broome on the 30th May, and north of Montgomery Reef on the 1st of June. The Charter boat “Matrix” recorded 4 adult whales near Hall Point in Camden Sound on the 2nd of June. Mothers with late calves were still being sighted in Camden Sound, Collier Bay and near Broome in the first week of October. Many different cetaceans have been sighted along the coast. Pilot whales, Pygmy Killer Whales, Killer Whales, Spinner Dolphins, Bottlenosed Dolphins, Dugong and Australian Snub-fin dolphins have all been recorded. One Great White Shark was seen to the west of James Price Point, and a whale shark was sighted feeding at the mouth of Barred Creek. Many larges schools of baitfish, mackeral and tuna were sighted between Broome
and the Lacepede Islands from April to the end of September. The 2009 Broome Billfish Tournament saw record fish numbers with 1136 fish raised, 782 strikes, 502 hook-ups and 335 Sailfish tagged over a six day period. 41 Marlin were raised with 37 strikes and 14 tagged. Large schools of fish were regularly noted on the sounder of MV Odyssey in Yampi Sound, Collier Bay and Camden Sound. Humpback Whales were observed feeding 10 nautical miles west of Broome, near Willie Creek, in Collier Bay, and near Hall Point in Camden Sound. Kimberley Whale Watching recorded 582 pods of Humpback Whales, representing 969 whales including 98 calves, in sightings between the 1st of July and the 19th of September. Sentosa Charters (Broome) recorded 112 whale interactions, representing 270 whale sightings, which included 41 calf sightings, between the 16th of July and 17th of
September 2009. Sentosa sighted many other whales that were not recorded. The combined data from Sentosa Charters and Kimberley Whale Watching is represented graphically on the map “2009 Whale Survey” overleaf.
Tuna leaping near Quandong Point.
Adult humpback whale pods Cows with calves Bottlenose Dolphins Australian Snubfin Dolphins Dugong
2009 Cetacean pod sightings
Surveys & Methods The Kimberley Whale Surveys consisted of 3 parts: 1. Extended boat surveys from the 10th of May until the 20th of September 2009 between Broome and the Prince Regent River on charter boat MV Odyssey. 2. An aerial survey between Broome and the Lacepede Islands on the 30th of August 2009. 3. Analysis of whale interaction data from Sentosa Charters from the 16th of July 2009, to the 17th of September 2009. The purpose of the 2009 surveys was to record the number of cetaceans along the coast between Broome and the Prince Regent River and to compare the distribution and concentration of adult Humpback whales and cows with calves between Broome and Camden Sound. Extended boat surveys on MV Odyssey were conducted as part of the extended charters along the Kimberley coast. The Wilderness Society chartered MV Odyssey to carry out a dedicated whale survey trip from Broome to Camden Sound and back to Cape Leveque. The survey track between Broome and Cape Leveque was the same on all of the
scheduled trips. There was variation in the survey track between Cape Leveque and Camden Sound throughout the year. Whale sightings were observed from the front deck of the boat, approximately 4m above the water. Whales could still be seen breaching approximately 5nautical miles from the boat. When a whale was spotted, the sighting was plotted on Odyssey’s GPS navigation chart. The compass bearing to the whale, relative to MV Odyssey’s position was recorded. The distance to the whale was then estimated and recorded. The estimated position of the whale was then plotted and recorded in degrees and decimal minutes (DDM). The estimated distance to the whale was reasonably accurate to within 1 nautical mile of the boat. That accuracy decreased as the distance to the whale sighting increased. Whale numbers were conservatively recorded and were based on surface sightings only. Cows and calves were easy to recognize and were recorded as cow/calf pairs. Any other whale sightings were recorded as adults. A hydrophone was deployed along the survey route to determine if bulls were singing in the area.
The vessel speed was consistently held at 8-10 knots. Many whales reacted to the passage of the vessel through the survey area. The whale sightings that were recorded only reflect the concentration and distribution of whales through the survey area over the time of the survey and should not be considered as the actual number of individual whales in the area. No statistical analysis of the data has been attempted to determine population numbers. Accurate population information can only be determined by individually photo identifying the whales. The 2009 sightings have been plotted on satellite images of the coast. The relative concentration and distribution of the whales between Broome and Camden Sound is graphically illustrated. The sightings reflect the number of transects through a particular area, or sighting effort. For example; very few whales were recorded between The Lacepede Islands and Cape Leveque, or around
Pender Bay, which is a well known whale resting and congregation area. Many whales have been sighted in the Pender Bay area this year from fixed observation points. Odyssey only travelled through the area in daylight hours on the 6th of September and the 7th of September 2009. The survey results and maps do not reflect the concentration and distribution of whales outside the survey tracks.
2009 Cetacean Sightings
Aerial Survey An aerial survey was conducted on the 30th August 2009 during the peak migration period to get an indication of the concentration and distribution of Humpback Whales between Gourdon Bay, to the south of Broome, and The Lacepede Islands to the north The survey was conducted in a Cessna caravan on floats., with 8 observers, 2 pilots and 2 recorders on board. The plane flew over the survey area at 750ft at a speed of 110knots. The survey track was entered into the plane’s GPS. When a whale was sighted, the GPS position was recorded, along with the compass bearing to the whales and the estimated distance. The number of whales in each pod and their surface behaviour was noted. After the flight, the approximate positions of the whales were plotted in a MapLite nav chart programme, and these were then recorded in decimal degrees and minutes (DDM). These co-ordinates were then plotted on Google Earth Pro satellite images. The estimated positions of the whales was less accurate than the boat based surveys
because two new variables came into play. The plane was traveling at 750ft above sea level and traveling at ten times the speed of the boat. No attempt was made to stream the GPS to take into account the lag between sighting the whales and recording the data. Despite these factors, the records are still a reasonably accurate indication of the concentration and distribution of the whales along the flight path.
Adults Cow/calf pair Bottlenose Dolphin
(Named by Nichola Baudin in 1802).
2009 Cetacean Sightings - Baleine Banks to Broome
Sentosa Charters Sentosa Charters conducted dedicated whale watching trips between Broome and Eco Beach between the 16th of July and the 17th of September 2009. Sentosa recorded the position of their whale interactions over that time. The position of the whales was noted in degrees and decimal minutes (DDM). They also recorded the number of adults and cow and calves. The GPS position of many other whales that were sighted during the course of their tours were not recorded. Sentosa records give an accurate indication of the whale population in the area from Broome to Eco Beach during the period from the 16th July to the 19th September 2009. See table 3.
Adult humpback whale pods Cows with calves Bottlenose Dolphins Australian Snubfin Dolphins Dugong
Sentosa Whale interactions 2009
Survey Results The results of the survey have been summarized in tables 1 to 3. Kimberley Whale Watching sighted a total of 582 pods, representing 969 whales, between the 1st of July 2009 and the 19th of September 2009. Ninety eight calves were sighted, which represents 10% of the population. The highest concentration of whales were recorded between Broome and The Lacepede Islands from the 19th of July to the 8th of August 2009. The highest concentration of whales in Camden Sound was recorded between the 14th of July and the 31st of July 2009.
Montgomery Reef at high tide (neap tides) September 2009
Collier Bay has emerged as an important resting area for cows and calves. On the 19th of September, 11 cows with calves were recorded between Collier Bay and the Horizontal Waterfalls. Two surveys tracked from Camden Sound to Cape Leveque. High concentrations of whales were recorded on the 10th of September (9.3 whales per hour of sighting eort), and on the 15th of September (8.6 whales per hour of sighting eort). Sentosa Charters recorded significant numbers of cows and calves in the Broome area. In the period between the 16th of July and the 31st of July, 4.6% of the whales recorded were
Montgomery Reef - Spring tides July 2009
calves. In the period between the 1st of September and the 17th of September, 28.5% of the population were calves.
New calf breaching off Cable Beach - August 2009
Cetacean pod sightings Collier Bay to Camden Sound Adult humpback whale pods Cows with calves Bottlenose Dolphins Australian Snubfin Dolphins Dugong
Table 1 - Cetacean Sightings 2009 Whale Survey DATE 26/07/09 14/09/09 06/09/09 14/09/09 08/09/09 09/09/09 19/09/09 27/07/09 23/06/09 - 20/09/09 05/07/09 31/07/09 6/07/09 - 20/07/09 11/08/09 - 15/08/09 07/09/09 15/09/09 10/09/09 30/08/09 01/07/09 - 6/9/09
2/7/09 -15/09/09 2/7/09 -15/09/09 2/7/09 -15/09/09 2/7/09 -15/09/09 2/7/09 -15/09/09 05/10/09
LOCATIONS Collier Bay Camden Sound Lacepede Islands to Beagle Bay Collier Bay Horizontal Waterfalls to Raft Point Collier Bay to Hall Point Collier Bay to Horizontal Waterfalls Camden Sound Incidental Camden Sound Camden Sound to Cockle Reef Camden Sound Camden Sound to Collier Bay Beagle Bay to Horizontal Waterfalls Camden Sound to Cape Leveque Camden Sound to Cape Leveque Aerial flight - Broome to Broome Broome to James Price Point
NO. PODS 8 9 9 13 15 15 15 16 21 23 24 25 26 28 62 Text 80 93 100 582
NO. WHALES 13 11 13 21 22 19 26 23 49 30 33 35 45 39 97 111 163 219 969
1 33 1 25 2 1
20 128 50 48 2 10
NO.CALVES 3 1 0 5 4 3 11 2 12 1 3 0 5 9 9 10 10 10 98
CETACEAN TYPE Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale Humpback whale
Pilot whale Pygmy Killer Whales Bottlenose dolphin Spinner dolphins Snub-fin dolphins Dugong Dugong
Table 2 - Comparison of selected survey tracks 1/7/09 - 19/9/09
Date 01/07/2009 19/07/2009 24/07/2009 02/08/1998 08/08/2009 17/08/2009 30/08/2009 06/09/2009 05/07/2009 14/07/2009 06/07/2009 27/07/2009 31/07/2009 14/09/2009 10/09/2009 15/09/2009 09/09/2009 26/07/2009 08/09/2009 14/09/2009 19/09/2009
Location Broome to Lacepede Islands Broome to Lacepede Islands Broome to Lacepede Islands Broome to Lacepede Islands Broome to Lacepede Islands Broome to Lacepede Islands Broome to Lacepede Islands Broome to Lacepede Islands Camden Sound Camden Sound Camden Sound Camden Sound Camden Sound Camden Sound Camden Sound to Cape Leveque Camden Sound to Cape Leveque Collier Bay to Hall Point Collier Bay Horizontal Waterfalls to Collier Bay Collier Bay Collier Bay to the Horizontal Waterfalls
Cetacean Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales Humpback whales
No.pods
Adult
6 17 19 15 18 11 93 12 5 18 17 16 24 9 80 62 15 8 15 9 15
13 29 43 27 27 16 143 13 4 24 24 20 27 9 91 79 11 7 14 7 4
Cow
Calf
4
4
10 2 1
10 2 1
2 3 1 10 9 2 3 4 4 11
2 3 1 10 9 2 3 4 4 11
Total whales
% calves
Observation hrs
13 29 43 27 35 16 163 17 6 24 24 24 33 11 111 97 15 13 22 15 26
0 0 0 0 11.42
3 3 4 1.5 4 1.5 2.25 4.25 1 2.25 2.5 4 6 6 12 11.25 2 3.5 5 1 5
6.1 11.76 16
8.3 9 9 9 9.2 13.3 23 18.1 26.6 42
Whales per hour sighting effort 4.3 9.6 10.7 18.0 7.8 8.7 72.4 4.0 6.0 10.6 9.6 6.0 5.5 5.5 9.3 8.6 7.5 3.7 4.4 15.0 5.2
Notes
Aerial survey
Sentosa Charters’ Whale Interactions July to September 2009
Incoming tide, Roebuck Bay - August 2009
Other Cetaceans The 2009 Cetacean survey recorded a number of exciting events. Approximately 20 Pygmy Killer Whales were observed working fish with 7 Humpback Whales near Willie Creek, just to the North of Broome in late July, and approximately 50 Spinner Dolphins were observed feeing on fish in Collier Bay. One of the highlights of the year was recording significant numbers of Snubfin Dolphins in the Prince Regent River. Previously thought to be Irradawaddy Dolphines, the Australian Snubfin Dolphin was only recognised as a seperate species in 2005. A pod of 6 Snubfin Dolphins was recorded on Hull Banks in Camden Sound. The IUCN has given the Australian Snubfin Dolphin the status of “data deficient�, but with high conservation priority. The dolphins are endemic to Australia and the Sahul Shelf in Indonesia.
Sampling bait - Prince Regent River
Australian Snubfin dolphins - Prince Regent River In July and August, most of the creeks in the Prince Regent River were full of prawns. Australian Snubfins are generalist feeders, feeding on fish, squid and crustaceans.
Moonrise Prince Regent River
Australian Snubfin Dolphin sightings
Discussion The results of the 2009 Kimberley Cetacean Survey indicate that the Kimberley coast between Gourdon Bay, to the South of Broome, and Camden Sound to the North, is an important habitat for the Breeding Group D population of Humpback Whales. Cows are calving between Broome and Camden Sound. High concentrations of whales near Broome were sighted near large shoals of baitfish, indicating that this may also be an important feeding area. Feeding behaviour was also observed in Collier Bay and near Hall Point in Camden Sound. Further studies are needed to survey the entire area between Eighty Mile Beach, Adele Island and Camden Sound, to determine, accurately, the concentration and distribution of whales along the Kimberley coast. Humpback whales are identified by the unique pattern of scalloping and black and white patterns on their tails, so a comprehensive effort needs to be made to photo identify individual whales, in order to gain a more accurate determination fo the size of the population of Humpback Whales in the Kimberley region.
Calf feeding behaviour off Willie Creek - August 2009
Complex currents mobilize sediments on the south side of Montgomery Reef with a big incoming spring tide. Image courtesy Dr Greg Jacobs 2009
Marine Protected Areas The Western Australian State Government has just announced the establishment of a whale sanctuary in Camden Sound. This should be viewed as the first step toward establishing Marine Protected Areas (MPA) along the Kimberley coast. Camden Sound has been regarded as the main maternity area for the Breeding Group D population of Humpback Whales. The results of the 2009 Kimberley Whale Watching survey indicate that Collier Bay and the area between Broome and the Lacepede Islands are also important calving grounds. A Kimberley whale sanctuary should include the whole area outlined on the map overleaf. The boundary should not be limited
to State waters, but should include Commonwealth waters outside the 3 nautical mile limit. Australia has an international obligation to protect the habitat of endangered species.
Suggested boundary for Marine Protected Area
Threats to Kimberley Cetaceans
Mangrove communities in Roebuck Bay
The Kimberley marine environment is a unique and productive ecology that has developed over the past 8-10,000 years. The productivity of the Kimberley coast is dependent on a unique set of conditions that are influenced by major ocean currents, huge tidal fluctuations and inshore currents that are constantly mobilizing and shifting sediments through the area, along with seasonal inflows of freshwater and nutrients from rivers that rise on the ranges of the Kimberley Plateau. Significant coral communities are established in fringing reefs around most of the islands. Seagrass meadows and sponge gardens support many species. Productive tidal flats are exposed at low water in many areas, and these support many resident and migratory birds. Huge mangrove communities provide the nutrients that are the start of the food chain in many areas.
Buccaneer Archipelago
The Dampier Peninsular, from Gourdon Bay near Broome, to the Lacepede Islands, has been recognized as one of the “biodiversity hotspots� of the Kimberley coast. The area is rich in marine life. The marine environment at the Baleine Banks to the west of The Lacepede Islands is connected through the tides to the rich mud flats and seagrass meadows of Roebuck Bay. Seagrass meadows in Roebuck Bay The waters of Roebuck Bay are connected to Roebuck Plains through subterranean saltwater streams that extend for miles to the east. The health of this unique marine environment depends on maintaining the health of the plains country to the east, the mangroves, and the saltwater country along the Dampier Peninsular. This area is home to many fish species, cetaceans, dugong and turtles. Many of these species are listed as vulnerable to extinction.
An incoming spring tide pushes down the coast from The Lacepede Islands through Roebuck Deeps into Roebuck Bay.
In 2007, the WA state waters from the high water mark to the 3 nautical mile limit were opened up for oil and gas exploration and development. This area includes the reefs and banks around the Lacepede Islands to the high water mark. In 2008 the West Australian Government announced the development of an industrial “precinct� at James Price Point, 60km north of Broome, to process gas from the Browse Basin. The development will be approximately 3000ha. The gas precinct will require constant dredging of shipping channels, the establishment of breakwaters and an influx of industrial shipping of approximately 3-5 shipping movements per day.
A calf breaches off Cable Beach, August 2009.
Discharges from the processing facility could threaten the health of the marine environment. Heavy metals and oil will be pumped into the ocean if the current environmental standards apply. At present the oil and gas industry is allowed to discharge 30-50mg of oil in every litre of produced formation water (water discharged from the well-head) into the marine environment. The ongoing West Atlas oil rig disaster in
The leaking West Atlas oil rig, operated by Thai company PTTEP.
the Timor Sea is a timely reminder of the threats to the marine environment posed by the environmental impacts of the oil and gas industry. The discovery of oil and gas on Roebuck Plains poses a similar risk The West Atlas oil rig in the A dead whale in the mangroves, on Thangoo Station. The visible brown lines are dead mangroves, killed by the inundation of whale oil from rendered down blubber leaching into the mangrove drainage channels.
Timor Sea has been discharging at least 500,000 litres of oil per day into the marine environment since the 21st August 2009. As at the 14th October 2009, PTTEP, the Thai operators of the West Atlas oil rig, have failed in their second attempt to stem the flow of oil by injecting heavy mud into the leak. If a comparable oil spill occurred in state waters along the Dampier Peninsular, it would wipe out the corals, seagrass meadows, sponge gardens, mangroves and benthic (sea bed) communities. In late September 2009 a dead adult Humpback Whale was washed into the mangroves at the southern end of Roebuck Bay on the King Tides. The oil from one whale has killed the mangroves along the mangrove drainage channels downstream from the whale (see image on previous page). There is an urgent need for the state and federal governments to review their development plans for the oil and gas industry in northwest waters. Royal Dutch Shell’s decision to proceed with floating LNG technology presents the best option for developing Browse gas.
Images available from Kimberley Media website www.kimberleymedia.com.au
ACKNOWLEDGEMENTS With very special thanks to the following: The owners and crew of Odyssey; Nick and Lorie Linton, Matt Dawson, Amber Thompson and Tess Harry for their help and generosity this year during our whale surveys. Carmen Griffen for patiently, and with endless good humour, typing out a LONG list of co-ordinates whilst ‘on holiday’. Horizontal Falls Adventure Tours (Rhys Thomas) for donating flight time for an aerial whale survey on the 1st of September 2009. The Wilderness Society for contributions toward a helicopter photographic expedition on the 1st of September 2009. Members of The Wilderness Society for contributing to data collection during a dedicated whale survey trip. Broome Helicopters King Leopold Air
DEC Broome Val and Cam Birch, and crew, Sentosa Charters, Broome who diligently recorded whale interactions over the 2009 whale watching season. These records are an integral part of the report. Professor Michael Williamson, Wheelock College, Boston, Mass. For his expertise and suggestions. Mark Staniforth, St Maryʼs College, Perth. Martin Pritchard (Environs Kimberley) and Piers Verstegen (Conservation Council WA) for their assistance on the Broome aerial survey.