Southern right whales are recovering slowly from near extinction caused by historical whaling. Due to the relatively small numbers of whales that breed off the Australian coast, the species is listed as Endangered under the Environment Protection and Biodiversity Conservation Act 1999.
The National Recovery Plan for Southern Right Whales 2023–2033 provides a framework for collaborative efforts between countries and other stakeholders to protect and rebuild populations.
For what is considered to be a western population, there is strong evidence of population growth and expanding calving and nursing habitats, but some population parameters are becoming more variable and may be changing. There is little evidence to support similar growth in what is considered to be an eastern population. The evaluation of any population growth, however, is hampered by the predominantly opportunistic nature of the available data for the eastern population.
This project will deliver priority information through four, linked avenues of research on southern right whales through:
- updating population abundance trends via aerial surveys of the western population and improving photo-identification data flow (led by Murdoch University);
- Updating the Australian Right Whale Photo-Identification Catalogue (ARWPIC) with archived photos of eastern and western populations, and collecting photos of the western population to identify biologically important reproductive areas and contribute to the estimation of population parameters (led by Edith Cowan University);
- developing ways to combine opportunistic and more formally collected observations, to expand the utility of datasets (led by CSIRO); and
- collecting movement and genetic data to assess the connectivity and population identity of whales at the boundary of the eastern and western subpopulations (led by Flinders University).
Additionally, future research needs will be identified and linked through consultation with commonwealth and state government agencies, and research agencies.
1. Population monitoring of the western population of southern right whales
Annual aerial surveys of southern right whales have been conducted from Perth (Western Australia) to Ceduna (South Australia) since 1993 as part of a long-term monitoring program. The data collected have been used to estimate relative abundance, population trends, and reproductive parameters for the western population. The surveys have been funded by the National Environmental Science Program since 2015.
This project will continue these surveys in August 2023 and 2024, with photos and associated metadata uploaded to the Australian Right Whale Photo-Identification Catalogue (ARWPIC). Population metrics for the western population will be calculated using mark-recapture information derived from photo-identified individuals, contributing to determining and updating long-term population trends.
This subcomponent will further this initial work by refining the open source algorithm used by Flukebook and developing tools to provide an interface with ARWPIC to automatically integrate images and associated image metadata into the catalogue. Existing artificial intelligence image recognition algorithms, such as used in the North Atlantic right whales platform Flukebook, will be refined to automatically integrate images and associated metadata from various sources (i.e., land-based monitoring and opportunistic datasets) into ARWPIC. This will increase efficiencies in processing photo-identification images, fast-tracking transfer of data required for estimating population parameters.
2. Southern right whale aggregation area assessment
Progress in updating the status of southern right whale aggregation areas for national recognition as Biologically Important Areas (BIAs) is variable across Australia. A collaborative approach will be taken to collate and upload archived photos from the eastern and western southern right whale sub-populations. In addition, collection, upload, and processing of existing opportunistically collected images and targeted surveys to expand photo-identification information in data-poor locations of the western-subpopulation will be undertaken, including:
- Albany to Hopetown, WA (by the community group South Coast Cetaceans);
- Ngari Capes Marine Park (by citizen science and research groups Western Whale Research and Southwest Whale Ecology Study);
- Eastern Flinders Bay (vessel-based surveys); and
- Esperance region (aerial surveys).
3. Expanding utilisation of southern right whale datasets to estimate national population parameters
Measuring and monitoring population recovery are central to measuring the success of conservation management. Many of the opportunistic observations of southern right whales, however, provide an insufficient basis for establishing the necessary biological and population parameters needed to determine the status of the population, whether the population is recovering and at what rate it is recovering. There is therefore a need to identify and develop methods that can incorporate opportunistic datasets to facilitate their use in better understanding how the population of southern right whales in Australia is faring.
Following on from previous NESP projects, statistical approaches will be developed that combine opportunistic observations and systematically collected observations to allow the estimation of population parameters for informing conservation management plans.
4: Movements, connectivity, and population identity of southern right whales at the boundary of the eastern and western subpopulations
Understanding the movements and migration pathways of individuals, and the nature and degree of difference between the two subpopulations, is a priority objective of the species’ conservation management plan. Encounter Bay, SA, is a ‘small aggregation’ area for southern right whales and is located at a midway point between the two recognised subpopulations. Research is needed to clarify the boundary between the sub-populations, and whether the Encounter Bay aggregation should be considered part of the western or eastern management group.
This work will include satellite tracking of unaccompanied adults, minimally invasive sampling of non-calf individuals for genomic analysis, and photo-identification in Encounter Bay and adjacent waters. Satellite tracking will focus on unaccompanied adults because they are expected to move more frequently along southern Australia, are more likely to be exposed to interactions with regional marine industries, and may be decreasing in numbers, according to recent aerial survey observations. The tracking data will be used to model whale movements, occupancy, and behaviour, and assess potential risks posed by human activities.
Genomic analyses will allocate individuals to subpopulations and re-assess stock structure and connectivity across Australia and with New Zealand, in collaboration with University of Auckland researchers. Movement and genomic data will complement other satellite tracking and isotopic studies in south-western Australia (Macquarie University) and New Zealand (University of Auckland) focusing on the whales’ movements to foraging grounds.
The project team will work with Indigenous groups to identify and develop appropriate ways to collaborate with and communicate the goals, findings and reciprocal benefits of this research to Indigenous people. This will include:
- presentations to the Yalata Aboriginal Community;
- knowledge sharing and identification of opportunities for capacity building through regional representative corporations in WA and SA; and
- workshops in South Australia to understand Indigenous knowledge and the cultural significance of southern right whales in the study region.
The findings of this project will advance the conservation management of Endangered southern right whales in Australia through:
- more efficient provision and processing of photo-identification images and data transfer for estimating population parameters;
- within region matching of individuals across key eastern and western aggregation areas, providing the basis for estimating minimum abundance, residency, site fidelity, and connectivity
- a national framework for expanding the datasets available for estimating population estimates, rates of change and connectivity;
- information and mapping to update the national conservation management plan, profile and threats database, BIA maps for use in marine park management, and risk assessments for marine industries and tourism; and
- expanded partnerships to help manage Sea Country, promote sustainable use and species recovery, and share Indigenous knowledge.
Southern Australian waters
Edith Cowan University
Department of Climate Change, Energy, the Environment and Water