Oral Presentation Australian Society for Fish Biology Conference 2024

Developing and testing a multi-species harvest strategy for the Southern and Eastern Scalefish and Shark Fishery (111276)

Richard Little 1 , Paul Burch 1 , Andre Punt 1 , Beth Fulton 1 , Pia Bessell-Browne 1 , Geoff Tuck 1 , Sean Pascoe 1 , Ian Knuckey 2 , Keith Sainsbury 3 , David Smith 1 4
  1. CSIRO, Hobart, TAS, Australia
  2. Fishwell Consulting, Queenscliff, VIC
  3. SainSolutions , Hobart, TAS
  4. AFMA, Canberra, ACT

The Australian Southern and Eastern Scalefish and Shark Fishery (SESSF) is a multi-sector and multi-species federally managed fishery. While the fishery interacts with more than 100 species, around 30 species are harvested commercially, with a dozen accounting for more than 75% of the Gross Value of Production (GVP). Management of the fishery relies primarily on output controls for the key commercial species (i.e. targeted) and several byproduct species. Total Allowable Catches (TACs) are currently determined for 34 stocks based on harvest control rules that are functions of single-species target and limit reference points and allocated as individual transferable quotas (ITQs). Increasingly, negative indicators of the fishery have been seen, which include: (a) TACs failing to be caught, (b) catch-per-unit-effort (CPUE) appears to be declining across most species; and (c) stocks below limit and target reference points appear not to be recovering. At the same time management costs are rising. We have attempted to address these concerns by developing options for a new harvest strategy that addresses two principal challenges of managing multi-species fisheries: technical interactions exhibited by a diverse fleet, and the large number of quota species needed to be managed under limited resources. Approaches were considered that reduced the frequency of annual assessments, and incorporated incidental catches of byproduct species in setting RBCs under a harvest control rule. The strategies were evaluated in a simulation framework using management strategy evaluation, and indicated the need to consider additional factors in assembling a harvest strategy, including factors that buffer the risk associated of not doing an annual assessment, and balance the risk of under-fishing commercially-important species at the expense of constraining over-fished species.