|
|
|
 |
2006/07 Grant funded projectsDr Peter Gill and Ms Margie Morrice Using aerial surveys, small vessel tagging and behavioural studies, and satellite remote sensing this program aims to understand the population status of and habitat use by foraging and feeding blue whales in the Bonney Upwelling blue whale feeding ground and adjacent waters. This work will also increase our understanding of baseline behaviour, partly to assess effects of proposed seismic exposure experiments. This is a globally important feeding ground for this endangered species, and this work will enhance our understanding of blue whales' habitat requirements, improve our ability to monitor their status, and better allow us to assess their responses to human disturbance.
Demersal gillnet fisheries in Australia have reported a level of incidental mortality of the "Vulnerable" Australian sea lion (ASL) in Western Australia. Australian sea lions forage extensively on the benthic habitats of the continental shelf from shallow waters (<20m) to the shelf edge (~200m), overlapping with the demersal gillnet fisheries. This project will determine the foraging ranges of ASL sub-populations and how they overlap with the fishing effort as determined by logbooks and vessel monitoring systems used in the fishery to provide information for potential mitigation of bycatch through temporal/spatial management options.
This project is examining telomere dynamics in cetaceans and the potential to use them to gather demographic information for individuals (i.e. age estimates) or species (i.e. ontogenetic longevity estimates) in a minimally invasive fashion, from a small skin sample. If telomeres prove effective biomarkers for either/both of these demographic facets, they can provide a means to gather useful demographic data that otherwise can rarely be gathered from live individuals (i.e. age estimates) or as of yet do not exist (i.e. longevity information for Southern Right Whales and others), both of which are important parameters in quantifying status and assessing impacts on populations.
Traditional methods of censusing Australian sea lion populations have used visual counts of pups during the peak of the protracted pupping season to provide a point estimate that can significantly underestimate pup production. As a consequence, quality time-series data on the status of populations are essentially absent. Effective management and recovery of Australian sea lion populations will need to be underpinned by an ability to detect changes in the status of populations over the shortest possible time-periods. This proposal builds upon a project funded by NHT/MSRP in 2006 to develop new population monitoring methods for the threatened Australian sea lion.
The phenomenon of cetacean mass strandings remains poorly understood, despite the tremendous efforts often devoted to the rescue attempts during these tragic events. We propose to investigate the population structure and social dynamics of long-finned pilot whales - the primary species involved in mass strandings, by combining ecological and genetic information from more than 600 samples collected in Tasmania and New Zealand. This study is expected to provide new information on the status of pilot whale populations around Tasmania and New Zealand and advice for improved management of animal welfare in future stranding events.
Understanding the dynamics of populations and impacts of human interactions requires knowledge of individuals' ages. Few people in Australia have the expertise to prepare and analyse marine mammal teeth for age estimation. Establishing a centre for this technique and running a workshop would alleviate the difficulties and costliness of sending researchers and/or specimens overseas. The South Australian Museum is well placed to house a centre for tooth aging since it has Australia's largest and most comprehensive marine mammal collection, and an active research program. A study on bottlenose dolphins aims to relate age to toxic contaminant levels and life history data, information that does not exist for Australia and is necessary for conservation and management of inshore dolphins.
The Australian Antarctic Division is developing a small, biologically inert, blubber-implantable satellite tag to monitor the movements of baleen whales, in particular humpback, blue and southern right whales. The effective development of a capacity to determine the movements of large cetaceans will enable researchers to address major components of federal and state based conservation management plans, as well as provide data and advice to international fora. More specifically, the satellite telemetry of blue whales and southern right whales is detailed as a high priority in the respective recovery plans. The tracking of these and other whales is also noted as a priority in the Action Plan for Australian Cetaceans.
The project will complete a major existing aerial survey long-term data set from which information has been accruing annually, off southern Western Australia over 30 years, and off southern Australia (C Leeuwin WA - Ceduna SA) for the past 14 years (the latter due for completion after 15 years in 2007). It will maximise return on past research investment, and contribute towards management and conservation of right whales in Australian waters by providing:
This project will conduct the first cross-jurisdictional aerial survey of the entire coastal waters of the Gulf of Carpentaria for dugongs to provide: (1) a robust estimate of sustainable anthropogenic mortality of dugongs for the region surveyed, (2) a geo-referenced map of dugong distribution and abundance, and (3) statistical comparisons with previous surveys of parts of the region to inform: (1) the National Approach to Sustainable Harvest of Marine Turtles and Dugongs in Australia, (2) Marine Bioregional Planning in the Gulf of Carpentaria, and (3) initiatives to reduce bycatch in the Gulf's inshore gill net fisheries.
A spatial model of dugong distribution and relative density in Torres Strait will be produced from data integrated across six aerial surveys from 1987-2006. The resultant map will be provided to Islander communities and management agencies to inform negotiations about shared responsibility strategies for ensuring that the Torres Strait dugong fishery is sustainable as part of the National Approach to Sustainable Harvest of Marine Turtles and Dugongs in Australia. The spatial model will also be used to determine if nutrient density of seagrass is a major forcing factor of dugong distribution and relative abundance in Torres Strait.
This PhD project will develop methodologies to assess the reproductive state of wild dugongs via non-invasive hormonal profiles in exhaled air and faeces, and will calibrate these profiles against saliva and blood. These data will be used along with gender, body size and social association data gathered during mark-recapture studies, to determine the reproductive status of individual dugongs. Life history parameters determined during this study will be incorporated into a population study of dugongs in Moreton Bay, southern Queensland. An understanding of reproductive behaviour and biology is crucial if we are to develop useful models of population dynamics.
This project will gene-tag dugongs in Moreton, Hervey and Shoalwater Bays to obtain key information on the structure, dynamics, connectedness and stock size of these 'urban' dugong populations in southern Queensland. Microsatellite DNA from skin and faecal biopsies will be used to individually identify dugongs and sex specific primers used to determine gender. These remote sampling techniques will allow us to rapidly identify and characterise a significant proportion of each population. Population genetic analysis will be used to define regional management units for dugongs in southern Queensland, identify migration between these major populations and determine stock size(s) and composition.
The east Australian humpback whales were hunted to near-extinction in the early 1960s. Since the early 1980s land-based abundance surveys have been conducted at Point Lookout off Brisbane where most of the whales pass close to land. The last survey was performed in 2004 and in order to continue monitoring the recovery of this population, we propose conducting a short survey in 2007. Absolute abundance estimates have historically relied on a number of assumptions concerning the offshore distribution and detectability of passing whales and we also propose to test some of these assumptions with concurrent aerial surveys. Results of these will enable us to improve the accuracy of future absolute abundance surveys. Concurrent acoustic recordings of the passing whales will also be used to help develop acoustic census techniques.
We will develop nuclear microsatellite genetic markers specific for blue whales, which will provide powerful tools for identifying stocks of blue whales worldwide and, potentially, as diagnostic markers for differentiating subspecies. We will also infer population genetic structure of the two main Australian feeding aggregations using mtDNA control region sequences and a large panel of microsatellite markers to investigate potential genetic subdivision between areas. This study will fulfil one of the actions of the Blue Whale Recovery Plan by gathering information on population structure and therefore providing indicators of structure to be incorporated into models for measuring recovery and status.
A/Professor Rob Harcourt and Dr Natalie Patenaude Delineation of stock boundaries is fundamental to management of protected species. For the southern right whale, determining the level of genetic interchange is essential to accurately assess population status and rates of change, to evaluate impact of anthropogenic threats eg entanglements or boat strikes, and to delineate critical habitat in Australian waters. The primary objective is for on-going collection of genetic samples from remnant populations. This will be used to formulate a larger study that will be used to identify genetic stock structure and the level of gene flow between localities across southern Australia.
|
 
|