Project number: 2011-077
Project Status:
Completed
Budget expenditure: $68,976.00
Principal Investigator: Paul J. Rogers
Organisation: SARDI Food Safety and Innovation
Project start/end date: 14 Jun 2012 - 29 Jul 2013
Contact:
FRDC

Need

Please consider this proposal under Theme 1. Demonstrating Sustainability: Evidence based and low-risk management for Shark-Associated Fisheries.

Information on the genetic population structure of shortfin makos was identified as a research priority at the recent FRDC-funded Australasian Mako Shark Workshop. A support letter was provided by the PI of the workshop, Barry Bruce of CSIRO, Hobart (find attached).

At the workshop it was highlighted that:
1) completion of the current population structure study was a high priority,
2) further sampling resolution was required for the Indian Ocean.

Declines in shortfin mako populations in the Northern Hemisphere led to the listing of this species as ‘Vulnerable’ by the International Union for Conservation of Nature (IUCN) and the Convention on Migratory Species (CMS). The CMS listing led to the nomination under the Australian Commonwealth Environmental Protection Biodiversity and Conservation Act (EPBC Act, 1999). The listing was debated by stakeholders and was later amended.

A representative from the Australian Fisheries Management Authority indicated that information on the abundance of shortfin makos was a priority for management of Commonwealth fisheries. This proposal addresses this priority for shortfin makos in the Australasian region.

There is limited evidence that shortfin makos make cross-equatorial migrations. Satellite tracking of juveniles by the PI showed restricted northward movements. This suggests that the Southern Hemisphere may comprise one or more independent stocks. This has important implications for management.

Outcomes will be used to inform decisions on whether to manage shortfin mako stocks at ocean basin and/or cross ocean-basin scales, or as discrete spatial units within smaller regions. This will greatly enhance our capability to make recommendations to State and Commonwealth government agencies chartered with managing pelagic fisheries, as well as during the development of fishery risk assessments and Threatened Species Recovery Plans in the future.

Objectives

1. To use new genetic data to assess the patterns of population structure of shortfin makos within the Australasian region
2. To compare the geographic scale of genetic connectivity with migration patterns determined from satellite tags deployed on juveniles
3. To incorporate our dataset within a larger global study and elucidate the degree of cross-equatorial dispersal of shortfin makos
4. To use the data to determine the genetic effective population size of identified spatially discrete stocks
5. To provide advice regarding the appropriate spatial scales for management of fisheries that interact with shortfin makos in the Australasian region.

Related research

Environment
People
Industry
PROJECT NUMBER • 2023-085
PROJECT STATUS:
CURRENT

Snapper Science Program: Theme 1 - Biology and Ecology

1. Quantify the abundance of age 0+ Snapper in northern Spencer Gulf and Gulf St Vincent to provide relative estimates of recruitment for 2024, 2025, and 2026. Examine the otoliths of these fish to improve the understanding of early life history processes.
ORGANISATION:
Flinders University