Standard Presentation (15 mins) Australian Marine Sciences Association 2022

Citizen science offers a window into the influence of environmental factors on sailfish catch distribution (#113)

Laura M Smith 1 , Jessica A Bolin 2 , Julian G Pepperell 3 , Samuel M Williams 4 , Ian R Tibbetts 1
  1. School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
  2. University of the Sunshine Coast, Sunshine Coast, QLD, Australia
  3. Pepperell Research & Consulting Pty Ltd, Sunshine Coast, QLD, Australia
  4. Queensland Department of Agriculture and Fisheries, Brisbane, QLD, Australia

The sailfish (Istiophorus platypterus) is a highly mobile epipelagic billfish whose range extends across the world’s tropics and sub-tropics. Sailfish occur seasonally across northern Australian waters, where many recreational anglers enjoy catching them for sport. Anglers have contributed sailfish observations as citizen scientists through tagging programs since the 1980s. Despite the strong interest in this eye-catching species from recreational anglers, the ecology of sailfish throughout the central Indo-Pacific is poorly understood.

Environmental drivers of billfish movement and habitat use include factors such as sea surface temperature, productivity, and complex water mixing. This research aims 1) to determine which environmental factors influence sailfish availability to recreational fishers across different regions of northern Australia; 2) to characterise the seasonal and inter-annual variability of recreational sailfish catches; 3) make predictions about changes to sailfish availability in a changing climate. Sailfish catch distribution is modelled using observation records from long-term recreational tag-recapture datasets and associated oceanographic data derived from remote sensing products. It is important to understand the drivers of sailfish occurrence to elucidate current movement patterns and better predict potential range shifts in response to warming waters and changing ocean dynamics.