The Australian Snubfin Dolphin - A case for legal protection
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A case for legal protection The Australian Snubfin Dolphin
A report prepared by Dr Ray Nias, TierraMar Consulting, for WWF-Australia May 2011. Written and edited by Lydia Gibson, WWF-Australia. Cover photograph: © Deb Theile. Published in Brisbane, Queensland 2011 by WWF-Australia. Any reproduction in full or in part must mention the title and credit the above-mentioned publisher as the copyright owner. © Text 2011 WWF All rights reserved WWF is one of the world’s largest and most experienced independent conservation organizations, with over 5 million supporters and a global Network active in more than 100 countries. WWF’s mission is to stop the degradation of the planet’s natural environment and to build a future in which humans live in harmony with nature, by: conserving the world’s biological diversity, ensuring that the use of renewable natural resources is sustainable, and promoting the reduction of pollution and wasteful consumption.
CONTENTS
SUMMARY
Summary 03
THE AUSTRALIAN SNUBFIN DOLPHIN
What do we know about the Australian snubfin dolphin? 04
SNUBFIN DOLPHIN RESEARCH
Snubfin dolphin research 07
ACKNOWLEDGMENTS
Acknowledgements 12
Key references 12
© GUIDO J. PARRA
© DEB THEILE
Summary
SUMMARY
Australia’s unique snubfin was only described as
a separate species in 2005 and had previously
been thought to be a population of the Irrawaddy
dolphin that is found throughout south-east
Asia. Although little is still known about snubfin
dolphins, research in the past few years has shown
that the species is vulnerable to extinction and
many sub-populations may have disappeared
before they were even recorded.
There is no total population estimate for snubfin dolphins in Australia, but all recently
published estimates number less than 100 individuals in each sub-population on the east
coast, and less than 200 individuals in Roebuck Bay, Western Australia. Extrapolating
current estimates, one calculation suggests that the total number of snubfin dolphins may
now be less than 1000 ‘mature’ individuals. Of the few sub-populations that still exist many
may not be viable in the long-term. Population modelling has shown that the loss of even one
individual from human activities in addition to the natural mortality rate may be enough to
push a local subpopulation into unrecoverable decline.
Small sub-populations of snubfins are found in the shallow bays and estuaries of northern
Australia and evidence suggest that these habitats are now much less widespread than they
once were. As sea levels have risen since the peak of the last Ice Age some 20,000 years ago
many broad river valleys and coastal deltas have been submerged, limiting the remaining
habitat, particularly in north-western Australia.
We do know that snubfin dolphins now live in isolated small groups in habitats that have
already been disturbed by human activity. In-shore fishing with gill-nets and drift nets is
highly likely to have killed many hundreds of snubfin dolphins in the past and they continue
to be killed in gill net fisheries and by shark control measures designed to protect bathers.
Scars from collisions with boats are very frequent in some locations which may indicate that
many snubfins may die from boat collision without ever being recorded. Their remaining
coastal habitat is also subject to rapid development as many of Australia’s tropical regions
undergo dramatic industrial development as ports and terminals are built to support the
boom in mineral and energy exports.
Although Australia’s unique snubfin dolphin managed to survive massive environmental
changes over the past 20,000 years it appears it may not last another three generations.
The evidence that has been gathered on snubfins in the past few years by WWF, research
scientists, indigenous people and various partner organisations shows clearly it is time to
take action to prevent their decline and ultimate extinction. There is still a considerable
amount of research that needs to be done to understand snubfin dolphins and to be able to
manage threats to their survival.
For snubfins to survive the coming decades that there must be new and legally binding
protection of the remaining sub-populations that removes completely the threats of fishing,
boat strike and loss of habitat. This protection will require the Australian snubfin dolphin to
be legally recognised as threatened by the Australian Government and by the Queensland,
Western Australia and Northern Territory governments. The habitat of the remaining snubfin
dolphins needs to be safeguarded in strict sanctuaries that do not allow gill-net fishing and
shark-control measures. The snubfin dolphin also has Indigenous cultural significance for a
number of groups in the Kimberley, Northern Territory and Queensland and with the support
of these communities, it is critical that the species is legally protected under this criteria. Our
work has clearly shown that the role of coastal indigenous people as rangers and managers
of sea country and the species is important to recognise and strengthen. Finally in all areas
where snubfin dolphins occur there needs to be adequate control over other threats such as
boat strike and pollution which come with increased development and human activity.
The Australian Snubfin Dolphin page 3
What do we know about the Australian snubfin dolphin
© GUIDO J. PARRA
WHAT DO WE
The Australian snubfin dolphin (Orcaella heinsohni)
was first described as a separates species on the basis
of scientific studies carried out by Isabel Beasley
KNOW ABOUT
from James Cook University, Dr. Peter Arnold from
the Museum of Tropical Queensland and Dr Kelly
Robertson from the Southwest Fisheries Science
THE AUSTRALIAN
Centre , published in 2005. Previously this rarely
seen dolphin was thought to be the Irrawaddy
dolphin that can be found throughout South-east
Asia. Apart from a single record from Daru in Papua
SNUBFIN DOLPHIN
New Guinea, the snubfin is thought to be restricted
to Australia. They inhabit costal, shallow bays and
estuaries of the tropical and subtropical zones of
Australia from Roebuck Bay, Western Australia;
north through the Northern Territory and Gulf of
Carpentaria and south east to the Fitzroy River-
Keppel Bay region. Vagrant records exist from the Brisbane River and at Noosa
Beach in Queensland and the Dampier Archipelago, Exmouth Gulf, and Port
Hedland Harbour in Western Australia. There is also evidence that snubfin
dolphins previously occurred around the Ellis beach region between Cairns and
Port Douglas but disappeared sometime after seven animals were drowned in local
shark protection nets in the period 1996–2001.
At around 2.5m in length, the Australian snubfin dolphin has a rounded head
with no beak and large, broad paddle-like flippers. The dorsal fin, as indicated by
their common name is small and rounded. They live in small groups of less than
20 animals, and on average in groups of five. They may live to 30 years of age and
breed from nine years old, probably producing one calf every 2–3 years. This slow
reproductive rate combined with their low numbers is one of the key reasons why
they are very susceptible to extinction. Population models for the species suggest
that the loss of even one animal per year in addition to natural mortality will result
in the decline and eventual extinction of a local sub-population.
The Australian Snubfin Dolphin page 4What do we know about the Australian snubfin dolphin
LISTING OF THE SNUBFIN AS A The Australian snubfin dolphin is threatened with
extinction. On the basis of research surveys conducted
NATIONALLY THREATENED SPECIES in the past few years WWF is convinced that the
Australian snubfin dolphin meets all the requirements
IS A CRITICAL FIRST-STEP
to be listed nationally as a threatened species under
the Commonwealth Environment Protection and
TOWARDS THEIR PROTECTION
Biodiversity Conservation Act 1999. There is enough
evidence to suspect the species has declined by more
than 30% over the last three generations and that the
causes of this decline have not ceased. This decline is
© TAMMIE MATSON
expected to continue over the next three generations.
The low number of highly fragmented sub-populations
also means that the geographic distribution of snubfin
dolphins represents a highly precarious situation as the
isolated, small populations can quickly decline and go
extinct. Listing of the snubfin as a nationally threatened
species is a critical first-step towards their protection.
TWO OF THE KEY THREATS In the Townsville area 15 snubfins were known to have
been killed in shark nets between 1968 and 1976 and 41
TO SNUBFINS INVOLVE specimens currently in museum collections were caught
the same way between 1968 and 1990. From 1995 to
ENTANGLEMENT AND
2009 a total of 257 coastal dolphins were caught in
nets and drumlines associated with the shark control
DROWNING IN GILL-NETS
program (228 caught in nets and 29 on drumlines); 17 of
which were snubfin dolphins.
AND SHARK CONTROL Gill-netting for barramundi and other coastal fish began
in the late 1960s and is also suspected of being a main
MEASURES DESIGNED TO cause of the decline of the snubfin dolphin. In Western
Australia, a commercial fishery operating in Roebuck
PROTECT BATHERS Bay sets nets perpendicular to the mangroves as the tide
comes in. This fishery is part of the Kimberley Gillnet
and Barramundi Managed Fishery which extends from
the Western Australian/Northern Territory border to
the top of Eighty Mile Beach, south of Broome. This
fishery overlaps with snubfin foraging areas and the
setting of nets is therefore of considerable concern.
Since this fishery does not export it has not been
required to undergo a sustainability assessment under
Commonwealth environment legislation.
The Australian Snubfin Dolphin page 5What do we know about the Australian snubfin dolphin
KEY POPULATIONS NEED TO BE Although it is an offence to kill any dolphin species in
Australia, it is only in the Great Barrier Reef Marine
PROTECTED IMMEDIATELY IF THE Park that snubfin dolphins are afforded some degree of
protection through management actions. However even
SNUBFIN IS TO PERSIST OVER
within the Great Barrier Reef snubfin habitats are being
lost to industrial development and dolphins are killed by
THREE GENERATIONS
shark nets and gill nets. For the rest of Australia, there is
virtually no protection of snubfin dolphins.
The key sub-populations for the Australian snubfin
dolphin that need immediate protection are:
Queensland
1 Fitzroy River – Keppel Bay region
2 Repulse Bay north to Hinchinbrook
(including Cleveland Bay)
3 Princess Charlotte Bay and surrounding areas
Northern Territory
4 Cobourg Peninsula
5 Darwin Harbour
6 Blue Mud Bay and Sir Edward Pellew Island Group
Western Australia
7 Roebuck Bay
MAP OF AUSTRALIA 8 King Sound/Buccaneer Archipelago
OUTLINING KEY SUB- 9 Deception Bay
POPULATIONS FOR THE 10 Prince Regent River
AUSTRALIAN SNUBFIN 11
12
Drysdale River/Cape Londonderry
Ord River/Cambridge Gulf
DOLPHINS THAT NEED
IMMEDIATE PROTECTION
4
10
8 11 5
9 3
7 6
12
2
1
The Australian Snubfin Dolphin page 6Snubfin dolphin research
© TANYA VERNES / WWF-AUS
SNUBFIN DOLPHIN Surveys for snubfin dolphins in
Western Australia have been conducted
RESEARCH
by marine mammal research scientist
Dr Deb Thiele since 2004 and with
funding from WWF through the
Commonwealth Government’s Caring
for Our Country Program since 2008.
Dr Thiele carried out preliminary broad-scale surveys of the north-eastern Kimberley
coast in 2004 and 2006, recording 15 groups of snubfin dolphins, with a total of 88
individuals. Opportunistic surveys of other locations in the north-west were conducted
between 2007 and 2008; followed by fine-scale studies in Buccaneer Archipelago,
Napier Broome Bay region, Dampier Peninsula and Deception Bay in collaboration
with Indigenous rangers from 2009–2010 coordinated by the Kimberley Land Council.
Population assessment, habitat mapping and photo-identification surveys have been
conducted in Roebuck Bay since 2007. In Roebuck Bay, 161 snubfin dolphins have been
individually identified, indicating that this area is one of the most important ‘hotspots’ for
snubfin dolphins in Australia. Surveys by other researchers from Murdoch University have
also been conducted of around 1500 km of the northern West Australian coastline from
Coral Bay in the south-west to One Arm Point in the Northeast with sightings recorded for
the Dampier Archipelago, Roebuck Bay, and north along Cable Beach. Snubfins may also
occur as vagrants around the North West Cape and Port Hedland Harbour.
Research and surveys of snubfin dolphins has also been supported by ING DIRECT;
including the first dolphin research of its kind in the Northern Territory. Support from
ING DIRECT has also allowed for research projects to be conducted in Western Australia
and Queensland providing additional insights into where these dolphins feed and breed. In
Queensland specifically, this research has focussed on helping us to better understand the
level of gene flow between populations at the state level and determine just how vulnerable
some sub-populations might be. Overall, this valuable information allows us to build our
understanding of the types and scale of threats to snubfins in key habitat areas, as well as
raising public awareness to help ensure it gets the protection it deserves. This research has
culminated in a submission to the Australian Government that outlines the case for the
national listing and protection of Australia’s snubfin dolphin as a threatened species.
The results of all this work indicate that snubfin dolphins are found in extremely low
numbers and the small sub-populations are extremely isolated. This combination of factors
leads to a very high probability of extinction within a short period if current threats continue.
The Australian Snubfin Dolphin page 7SNUBFIN DOLPHINS ARE UNDER THREAT Snubfin dolphins are under threat from massive industrial developments Along the northern coast of Australia. One of the most significant and growing threats to snubfin dolphins (and a number of other coastal species such as marine turtles and dugong) is coastal development. Coastal development is often associated with activities such as construction, land reclamation, dredging, seismic surveys, drilling, blasting, increased commercial shipping, resource extraction, tourism, and recreational activities. In many cases all of these factors may operate together – posing a growing and cumulative impact. As a result there can be significant changes in the composition, structure and function of the coastal estuarine habitat and increased the potential for a wide range of direct threats including: • direct removal of habitat (seagrass, mangroves) • physical disturbance • sedimentation • increased vessel traffic • noise and chemical pollution.
© DEB THEILE
Snubfin dolphin research
© DEB THEILE
AUSTRALIA HAS Two of the most important sub-populations for long
term survival of the snubfin; in the Fitzroy River–
AN INTERNATIONAL Keppel Bay region in Queensland and Roebuck Bay
in Western Australia, are known to be at immediate
RESPONSIBILITY
risk. It is the cumulative effect of all threats that
is particular cause for concern. As populations of
TO APPROPRIATELY
snubfin dolphins are small and localised, they are
particularly susceptible to habitat degradation
MANAGE AND
and displacement from coastal activities. The
size and scale of the potential impacts of coastal
CONSERVE THE
development can be seen in the example of the
Fitzroy subpopulation. In and around the area of
SNUBFIN DOLPHIN
Gladstone in Queensland there are a number of
large-scale developments likely to have a negative
impact on the local snubfin population. The
proposed Balaclava Island Coal Export Terminal
at Port Alma and a cluster of developments for
the Gladstone Liquefied Natural Gas Project will
significantly reduce the extent and quality of
suitable habitat in the area as well as increasing the
volume of shipping and other activities that affect
snubfin dolphins. Similar large-scale developments
are likely to affect snubfin sub-populations in
Townsville and Weipa in Queensland, Darwin
Harbour (Northern Territory), and near Broome and
the Dampier Peninsula in Western Australia.
The Australian Snubfin Dolphin page 10Snubfin dolphin research
WWF IS WORKING WWF has been supporting comprehensive life
history and spatial use surveys for snubfin dolphins
TO CONSERVE THE (as well as other dolphin and large marine species)
in Roebuck Bay. The data collected are the first
SNUBFIN DOLPHINS OF
baseline data for marine wildlife in Roebuck Bay and
have already produced important scientific outputs
WESTERN AUSTRALIA
critical to local and broader regional management and
conservation in Kimberley marine environments. The
work that WWF has supported has also resulted in a
greatly heightened awareness of snubfin dolphins in
Roebuck Bay and throughout the Kimberley, through
community awareness efforts, media exposure and
most importantly due to the enthusiastic uptake of the
project by Traditional Owners and Indigenous Rangers
from Broome to Cape Londonderry. Knowledge sharing
and joint surveys conducted in collaboration with the
Kimberley Land Council, indigenous communities and
Indigenous Rangers have been a core component of the
project and have contributed directly to a much greater
knowledge of the distribution and relative abundance of
all three dolphin species inhabiting near-shore waters
in the Kimberley.
EXTINCTION IS A REAL Many of the world’s coastal and river dolphins
are threatened with extinction. The Baiji (Lipotes
POSSIBILITY FOR vexillifer) that once inhabited the Yangtze River of
China appears to be extinct and other coastal and
AUSTRALIA’S UNIQUE
river dolphins in Asia and other parts of the world
are known to be critically endangered. Unfortunately,
SNUBFIN DOLPHIN
the history of coastal dolphin conservation
indicates that by the time population declines are
noticed, and action taken, they may have passed
the point where conservation remedies are simple
or inexpensive to implement. Australia has an
international responsibility to appropriately manage
and conserve the snubfin dolphin and it is clear that
unless measures are taken soon it may suffer the same
fate as the river dolphins of Asia.
The Australian Snubfin Dolphin page 11Acknowledgements
ACKNOWLEDGEMENTS A report prepared by Dr Ray Nias, TierraMar
Consulting, for WWF-Australia May 2011.
Many thanks to Dr Isabel Beasley for her work on
the WWF-Australia EPBC nomination submission
for the snubfin dolphin and all the scientists that
reviewed the nomination including Daniele Cagnazzi,
Dr Deborah Thiele, Dr Guido Parra, Professor
Helene Marsh and Simon Allen. Many thanks also
to ING DIRECT for their ongoing support to WWF-
Australia’s snubfin dolphin campaign. Many thanks
to the Kimberley Land Council and all the Indigenous
Rangers that participated in the snubfin dolphin
surveys in Western Australia.
KEY REFERENCES Beasley I., Robertson, K. M. and P. Arnold.
2005. Description of a new dolphin, the
DESCRIPTION Australian snubfin dolphin Orcaella heinsohni
sp.n. (Cetacea, Delphinidae). Marine Mammal
Science. 21(3):365–400.
DISTRIBUTION AND Freeland, W. J. and P. Bayliss. 1989. The
Irrawaddy river dolphin Orcaella brevirostris in
NUMBERS coastal waters of the Northern Territory, Australia:
distribution, abundance and seasonal changes.
Mammalia. 53:49–57.
Parra, G. J., Schick, R. and Corkeron, P. J. 2006.
Spatial distribution and environmental correlates
of Australian snubfin and Indo-Pacific humpback
dolphins. Ecography 29: 396–406.
Parra, G. J., Azuma, C., Preen, A. R., Corkeron, P.
J. and Marsh, H. 2002. Distribution of Irrawaddy
dolphins, Orcaella brevirostris, in Australian waters.
Raffles Bulletin of Zoology, Supplement 10: 141–154.
Parra, G. J., P.J. Corkeron and H. Marsh. 2006.
Population sizes, site fidelity and residence patterns
of Australian snubfin and Indo-Pacific humpback
dolphins: Implications for conservation. Biological
Conservation 129: 167–180.
Perrin, W. F., G. P. Donovan and J. Barlow. 1994.
Gillnets and cetaceans. International Whaling
Commission – Special Issue 15.
Reeves, R. R., Jefferson, T. A., Karczmarski, L.,
Laidre, K., O’Corry-Crowe, G., Rojas-Bracho, L.,
Secchi, E. R., Slooten, E., Smith, B. D., Wang, J. Y.
and Zhou, K. 2008. Orcaella heinsohni. In: IUCN
2010. IUCN Red List of Threatened Species. Version
2010.4. . Downloaded on
20 March 2011.
The Australian Snubfin Dolphin page 12Key References
CONSERVATION Elliott, W., H. Sohl, and V. Burgener, 2009. Small
cetaceans, the forgotten whales. WWF Species
Programme, Gland, Switzerland. Available online
at: http://www.worldwildlife.org/who/media/
press/2009/WWFBinaryitem12794.pdf
Gribble, N. A., G. McPherson and B. Lane. 1998.
Effect of the Queensland shark control program
on non-target species: whale, dugong, turtle
and dolphin: a review. Marine and Freshwater
Research. 49:645–651.
Hale, P. 1997. Conservation of inshore dolphins in
Australia. Asian Marine Biology 14: 83–91.
Heinsohn, G. E. 1979. Biology of small cetaceans in
North Queensland waters. The Great Barrier Reef
Marine Park Authority, Townsville, Queensland.
Jefferson, T. A. and B. E. Curry. 1994. A global review
of porpoise (Cetacean: Phocoenidae) mortality in
gillnets. Biological Conservation 67: 167–183.
Lawler, I. R., Parra, G. J. and Noad, M. 2007.
Vulnerability of marine mammals in the Great Barrier
Reef to climate change. In. Climate change and the
Great Barrier Reef: a vulnerability assessment. Eds
J. E. Johnson and P. A. Marshall, Great Barrier Reef
Marine Park Authority and Australian Greenhouse
Office, Townsville, pp 497–513.
Paterson, R.A. 1990. Effects of long-term anti-
shark measures on target and non-target species
in Queensland, Australia. Biological Conservation
52: 147–159.
Reeves, R. R., B. D. Smith., E. A. Crespo and G. di
Sciara Notarbartolo. 2003. Dolphins, whales and
porpoises: 2002-2010 Conservation Action Plan
for the World’s Cetaceans. IUCN/SSC Cetacean
Specialist Group. IUCN Gland, Switzerland and
Cambridge, UK. 139pp.
Ross, G.J.B. (2006). Review of the Conservation
Status of Australia’s Smaller Whales and Dolphins.
Page(s) 124. [Online]. Report to the Australian
Department of the Environment and Heritage,
Canberra. Available from: http://www.environment.
gov.au/coasts/publications/pubs/conservation-
smaller-whales-dolphins.pdf.
WWF - Australia. 2010. Conserving Australia’s
unique costal dolphins. http://www.wwf.org.au/
publications/snubbyoct09/
WWF - Australia. 2010. Collision course: snubfin
dolphin injuries in Roebuck Bay. A report prepared
by Dr Deborah Thiele for WWF-Australia,
July 2010. http://wwf.org.au/publications/
snubfinreportcollisioncoursejuly2010/.
The Australian Snubfin Dolphin page 13FUNDING
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BY ING DIRECT
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THE AUSTRALIAN SNUBFIN DOLPHIN 2011
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WWF continues to promote sustainable
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