Opportunities and impacts of range extending scalefish species: understanding population dynamics, ecosystem impacts and management needs
Species-level responses to ocean warming is a priority research area as they underpin the structure and function of marine ecosystems and the productivity of fisheries that operate within them.
There are a number of range extending species that have become increasingly abundant in Tasmanian waters, providing new fishing opportunities for recreational and, to a lesser extent, commercial fishers. Species in this group include Pink Snapper, King George Whiting and Yellowtail Kingfish. While King George Whiting are known to spawn off the north coast it is unclear as to whether the other species have or are likely to become established as self-sustaining populations in Tasmanian waters or simply persist as spill-over from populations that are centered off mainland Australia. If the former is the case, it will be especially important to consider population attributes such as growth, mortality and reproductive dynamics relevant to the Tasmanian populations when developing and refining management arrangements to maximise the opportunities these 'new' species bring.
In addition, the broader ecosystem impacts of such range extending species, including competition with resident species at similar trophic levels, are unknown but could have consequences for other recreationally and commercially important species. Understanding these relationships will have benefits for the assessment and management of the Tasmanian recreational fishery more generally.
Final report
This work set out to quantify the biology and diet of three key range-shifting species in Tasmania with both recreational and commercial fishery value. The project was heavily reliant on engagement from the recreational fishing community and multiple citizen science initiatives, as well as historical data.
The information collected was used in modelling to predict how suitable habitats for each species may shift under future climate change projections. The work also indicated the potential changes to the ecosystem (such as food web) if these species’ ranges were to move.
