Fish sizes and growth in a warming ocean

Causes and consequences of fish size and growth changes in temperate marine coastal ecosystems

Degree type


Closing date

18 July 2022



Citizenship requirement


About the research project

Climate change and fishing is causing rapid changes in body sizes of many fish species. These changes are driven by multiple physiological and ecological processes, such as food availability, growth, reproduction, mortality and species redistributions. A recent study by UTAS researchers showed that in Tasmanian rocky reefs, average body lengths for many fish species are changing by 0.5-1% per year (Figure). The associated impacts of such fish body size changes on coastal fish communities and ecosystem functioning are likely to be significant, and implications for fisheries management and conservation remain largely unexplored.

This project will build on extensive IMAS and CSIRO research expertise in fish size ecology, fisheries, coastal ecosystems function and marine conservation. It will explore drivers and consequences of body size changes in coastal Tasmanian fish species using long-term underwater visual survey data, fisheries surveys, historical records, existing and new fish growth data, and physiologically structured size-based ecosystem models for Tasmanian rocky reefs. Specifically this study will:

  1. Apply Bayesian statistical models to understand changes in Tasmanian fish sizes through space and time, interactions with fishing levels, MPAs, presence of other species and multiple environmental indicators.
  2. Explore reasons for body size changes through detailed analyses of growth and size structure for ecologically and economically important Tasmanian coastal species.
  3. Implement size-based models developed for Tasmanian coastal ecosystems to assess impacts of body size changes (estimated in 1) and expected climate change impacts on fish communities and ecosystem dynamics. Assess performance of alternative fisheries harvest strategies/management measures to mitigate ecological and economic impacts of fish body size changes in a multi-species context.

Primary Supervisor

Meet Dr Asta Audzijonyte


Applicants will be considered for a Research Training Program (RTP) scholarship or Tasmania Graduate Research Scholarship (TGRS) which, if successful, provides:

  • a living allowance stipend of $28,854 per annum (2022 rate, indexed annually) for 3.5 years
  • a relocation allowance of up to $2,000
  • a tuition fees offset covering the cost of tuition fees for up to four years (domestic applicants only)

There is a top-up scholarship of $5,000 per annum (not indexed) for 3.5 years, with no extension, funded by Quantitative Marine Sciences (QMS) that will be considered for an outstanding applicant.

For this project, QMS will also cover the successful international applicant's single Overseas Health Cover (OSHC).

If successful, international applicants will receive a University of Tasmania Fees Offset for up to four years.

As part of the application process you may indicate if you do not wish to be considered for scholarship funding.


Applicants should review the Higher Degree by Research minimum entry requirements.

Additional eligibility criteria specific to this project/scholarship:

  • Applicants must be able to undertake the project on-campus.

Selection Criteria

The project is competitively assessed and awarded.  Selection is based on academic merit and suitability to the project as determined by the College.

Additional essential selection criteria specific to this project:

  • Demonstrated skills or strong interest in quantitative data analysis and size based modelling
  • Strong interest or experience in marine science and fisheries
  • Strong experience in using quantitative methods in R
  • Ambition to work with large datasets
  • Demonstrated proficiency in written and verbal English language

Additional desirable selection criteria specific to this project:

  • First-author publication (submitted, or close to submission) in a fish growth or size related topic
  • Knowledge of Australia's fishes and their basic biology

Application process

There is a three-step application process:

  1. Select your project, and check you meet the eligibility and selection criteria;
  2. Contact the Primary Supervisor, Dr Asta Audzijonyte to discuss your suitability and the project's requirements; and
  3. Submit an application by the closing date listed above.
    • Copy and paste the title of the project from this advertisement into your application. If you don’t correctly do this your application may be rejected.
    • As part of your application, you will be required to submit a covering letter, a CV including 2 x referees and your project research proposal.

Following the application closing date applications will be assessed within the College. Applicants should expect to receive notification of the outcome by email by the advertised outcome date.

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