This project aims to collect baseline data on the abundance, residency and genetic connectivity of Australian snubfin (Orcaella heinsohni) and Indo-Pacific humpback (Sousa chinensis) dolphins in state waters at several locations in the Kimberley region of Western Australia.
Using a combination of techniques, this study will greatly increase our understanding of inshore dolphin populations in a region coming under increasing pressure from coastal development. Our results will contribute to assessments of their conservation status and management in Western Australian waters.
This is a federally funded project through the Australian Marine Mammal Centre, with personnel including: PhD student Alex Brown (MUCRU); Chief Investigators Mr. Simon Allen, A/Prof. Lars Bejder (MUCRU) and Dr. Celine Frère (University of Queensland); and co-investigator Prof. Kenneth Pollock (MUCRU and North Carolina State University).
Little is known about the abundance and ranging of snubfin and humpback dolphins in the tropical northwest of Australia. Insufficient data exist on either of these species for the Department of Environment and Conservation (DEC) in Western Australia (WA) to assess whether they should be listed as Threatened or Specially Protected under the Wildlife Conservation Act 1950. Our knowledge of these two species in Australian waters comes from a few studies from eastern Queensland, where they are found in small, genetically discrete populations in near-shore areas (Parra 2006, 2011; Parra et al. 2002, 2004, 2006a, b; Cagnazzi et al. 2009). They are highly sensitive to habitat modification in the near-shore environment, and vulnerable to localised extinctions.
The mining and petroleum industries in north-western Australia are developing on a huge scale (Prospect 2011a, b). Through the associated creation and expansion of industrial ports and coastal processing facilities, the near-shore environment of north-western Australia is undergoing unprecedented, large-scale habitat modification. This threatens coastal habitats and the species that rely on them, such as coastal dolphins (Allen et al. accepted; Bejder et al. accepted; DEWHA 2010).
We seek to address the aforementioned data deficiencies by providing robust baseline data on snubfin and humpback dolphins at several sites in the Kimberley region of north-west Australia. We will estimate abundance, assess residency patterns and quantify genetic connectivity of these two species across the Kimberley region. This information will inform the conservation and management of snubfin and humpback dolphins in the region.
- Quantify abundance and residency patterns for Australian snubfin and Indo-Pacific humpback dolphins in state waters at several locations in the Kimberley region of north-west Australia.
- Use a landscape genetics approach to identify levels of structure and connectivity within and between dolphin populations across the Kimberley region.
At two study sites (Dampier Peninsula and Cambridge Gulf), a sampling regime of transects covering a ca. 50 km stretch of coastline out to 1-2 nautical miles will be surveyed by a small research vessel (Fig. 1). Estimates of abundance and residency patterns will be obtained using photo-identification survey techniques and capture-recapture analyses (following Pollock’s Robust Design – Pollock 1982, Pollock et al. 1990). Biopsy samples of animals will be obtained opportunistically during field work, using the Paxarms remote biopsy technique (Krützen et al. 2002), and subsequently analysed using a landscape genetics approach. Data will be collected over four seasons (two autumns and two springs) over two years, with ca. one month at a time spent at each study site.
A collaboration exists through the exchange of photo-ID images with a catalogue maintained by Dr. Deborah Thiele for Roebuck Bay. Logistical support and discounted facilities at Cygnet Bay are provided by Kimberley Marine Research Station.
- Allen et al. Accepted. Pacific Conservation Biology.
- Bejder et al. Accepted. Pacific Conservation Biology.
- Cagnazzi et al. 2011. Marine Mammal Science 27: 255-281.
- DEWHA 2010. Tropical Inshore Dolphin Workshop report. Townsville, 4-5 May 2010.
- Krützen et al. 2002. Marine Mammal Science 18: 863-878.
- Parra 2006. Journal of Animal Ecology 75: 862-874.
- Parra 2011. Unpublished Final Report to the Australian Marine Mammal Centre.
- Parra et al. 2002. Raffles Bulletin of Zoology 10: 141-154.
- Parra et al. 2004. Aquatic Mammals 30: 197-206.
- Parra et al. 2006a. Biological Conservation 129: 167-180.
- Parra et al. 2006b. Ecography 29: 396-406.
- Pollock 1982. Journal of Wildlife Management 46: 752-757.
- Pollock et al. 1990. Wildlife Monographs 107.
- Prospect 2011a. Western Australia’s International resources development magazine. April/May 2011.
- Prospect 2011b. Western Australia’s International resources development magazine. September/November 2011.