Project O.R.C.A. (Orca Research and Conservation Australia) is being undertaken by Centre for Marine Science and Technology (CMST) at Curtin University, Perth, Australia. This project adopts a multidisciplinary approach to investigate the distribution, abundance, bioacoustics and population dynamics of killer whales in Australian waters. Results from this study will provide pertinent data to address the population status of this species and deliver key scientific information for assisting management of Australian killer whales.
To date, there has been no dedicated acoustic study on the killer whale populations in Australia, and limited research has been conducted due to their transient nature and difficulty of obtaining data using conventional methods.
There is no reliable estimate of the population size of killer whales in Australian waters and population trends are unknown, with much of the information on killer whale distribution and occurrence obtained from incidental sightings.
Passive acoustic monitoring is a technique that can surmount this and allows us to obtain quantitative data, which will enhance our knowledge of this poorly known species in this region and provide the basis for future management and conservation.
This bioacoustics study provides the first quantitative assessment of the acoustic features of killer whale vocalisations in Australian waters, the sound environment they reside in, and presents an opportunity to further investigate this little-known population.
This acoustic research commenced in 2014 and has been on-going. We have already published the first paper describing the call repertoire of our Australian killer whales. Read more here.
POPULATION ABUNDANCE RESEARCH
By using methods such as mark-recapture, we can estimate the population size of certain populations in Australian waters. Using our photo-identification data taken over many years in the field, Honours student Emily Evans at CMST Curtin University is working to investigate the abundance of killer whales found in the Bremer Bay region, Western Australia. In 2017, Emily commenced an honours project under the Centre of Marine Science and Technology at Curtin University, supervised by Christine Erbe and Chandra Salgado-Kent. With the help of supervisors and Bec Wellard of Project ORCA, the team aim to quantify the first abundance estimate of killer whales in the Bremer Sub-Basin, Western Australia, using a non-invasive mark-recapture photo identification approach.
This research will provide the foundation for a long-term assessment of trends and changes in the killer whale population that is known to seasonally inhabit the Bremer Sub-Basin and assist in emphasizing the importance of conserving and managing the ecological value of the region.