Standard Talk (15 mins) Australian Society for Fish Biology Conference 2022

Changes in size and distribution of dolphinfish Coryphaena hippurus on the Australian east coast (#7)

Felicity E Osborne 1 , Julian G Pepperell 2 , Ross G Dwyer 1 , Andrew D Olds 1 , Daniel J Smith 3 , Samuel M Williams 3 4 , Ben L Gilby 1
  1. University of the Sunshine Coast, Sippy Downs, QLD, Australia
  2. Pepperell Research & Consulting Pty Ltd, Noosaville, QLD , Australia
  3. Department of Agriculture and Fisheries, Brisbane , QLD , Australia
  4. The University of Queensland, Molecular Fisheries Laboratory, School of Biomedical Sciences, St Lucia, QLD , Australia

Rapid changes in ocean characteristics have caused changes in species geographical range, as marine species are forced to acclimate or shift to more suitable conditions. Dolphinfish Coryphaena hippurus are highly migratory coastal-epipelagic species, whose temporal and spatial movements have been linked to changes in water temperature and are an important target for both recreational and commercial fishers. We assessed past and present distributions of dolphinfish by assessing the effects of ocean attributes (like sea surface temperature and primary productivity) on the distribution and movement of dolphinfish over time. Dolphinfish catch data was derived from the NSW DPI Game Fish Tagging Program from 2002-2020. We found that records of dolphinfish captures are changed in non-linear directions over time, being most northerly in 2010; this was possible related to SST. The average size of dolphinfish captured has increased over time, with larger fish typically recorded in locations with higher sea surface temperatures, lower primary productivity, higher velocity current flow and in water depths between 2000 and 3000 m. Understanding how marine species utilise ocean attributes in response to climate change and the implications the effects of climate change have on marine species is vital for the management of current and future fisheries and ocean health.