PhD opportunity:
The movement of fishes at the estuarine/freshwater interface
Background
Rivers and estuaries are among the world’s most severely anthropogenically impacted environments. The regulation of rivers and estuaries for water extraction and flood control is one of the major impacts on riverine fishes. Instream barriers can physically block the migration pathways of fishes preventing access to crucial habitat.
Fishways are structures that can enable passage of fishes over barriers and have been increasingly used to lessen the impact of dams on fish migrations. However, they can be expensive to construct and are not always effective at passing all resident species and the different life-history stages.
Assessing the effectiveness of fishways in relation to species life-cycles, migration patterns and swimming capability provides valuable information for designing more effective fishways. Moreover, assessing the impact of fishways on resident fish populations and communities in rivers and estuaries is crucial to determine their overall benefit in terms of improving river connectivity and population viabilities.
Western Australia has seven operational fishways, with the most recent planned for the Canning River at the Kent St Weir (KSW) (construction Feb-March 2017), which will be the first in an estuarine environment in south-western Australia. The KSW has recently been shown to impact on the connectivity of estuarine and freshwater fish populations and the planned fishway is aimed at passing as broader range of species and life-history stages as possible.
Project aims
· This PhD will use a range of contemporary fish tracking techniques, including acoustic and passive integrated transponder tags to determine the spatial and temporal movement of a range of species through the fishway and the adjacent freshwater and estuarine habitats.
· It will determine the swimming performance and aerobic scope of key species in the laboratory using a state of the art automated swim tunnel and respirometer.
· Relate these movement patterns with environmental factors in and outside of the fishway to determine the influence of extrinsic and intrinsic factors on fish movements.
· Compare the fish communities and populations downstream and upstream of the fishway pre and post- construction to assess its effectiveness in increasing habitat availability and population connectivity.
· Develop management recommendations to refine the existing fishway and criteria for future design of fishways in estuarine environments.
This project is externally funded and will suit a candidate seeking to conduct a project that involves a mix of contemporary ecological and laboratory based research that is highly applicable to the restoration and management of aquatic ecosystems. It will involve a combination of fish community ecology, population biology, telemetry (including surgery techniques), and physiology.
The project is based at the Centre for Fish and Fisheries Research and is externally funded by the Department of Parks and Wildlife. The successful candidate will be eligible to apply for additional stipend top-ups.
Scholarships available
The 2017 scholarship provides a tax exempt living allowance of AUD$26,682 per annum with potential top-up to $30,000.
Closing date – 4.30pm, Monday 31 October 2016.
Step-by-step application guide: http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Future-research-students/Admission-and-scholarships/Domestic-student-applications/
For more information:
Dr Stephen Beatty:
Ph: 9360 2813
http://www.murdoch.edu.au/Research-capabilities/Centre-for-Fish-and-Fisheries-Research/
http://www.freshwaterfishgroup.com/
https://www.facebook.com/Freshwater-Fish-Group-Fish-Health-Unit-342655079102312/