Shifts in the incidence of shark bites and efficacy of beach-focussed mitigation in Australia

Mar Pollut Bull. 2024 Jan:198:115855. doi: 10.1016/j.marpolbul.2023.115855. Epub 2023 Dec 2.

Abstract

Shark-human interactions are some of the most pervasive human-wildlife conflicts, and their frequencies are increasing globally. New South Wales (Australia) was the first to implement a broad-scale program of shark-bite mitigation in 1937 using shark nets, which expanded in the late 2010s to include non-lethal measures. Using 196 unprovoked shark-human interactions recorded in New South Wales since 1900, we show that bites shifted from being predominantly on swimmers to 79 % on surfers by the 1980s and increased 2-4-fold. We could not detect differences in the interaction rate at netted versus non-netted beaches since the 2000s, partly because of low incidence and high variance. Although shark-human interactions continued to occur at beaches with tagged-shark listening stations, there were no interactions while SMART drumlines and/or drones were deployed. Our effect-size analyses show that a small increase in the difference between mitigated and non-mitigated beaches could indicate reductions in shark-human interactions. Area-based protection alone is insufficient to reduce shark-human interactions, so we propose a new, globally transferable approach to minimise risk of shark bite more effectively.

Keywords: Beach meshing; Drone; Drumline; Shark attack; Shark deterrent; Shark mitigation; Surfer.

MeSH terms

  • Animals
  • Animals, Wild
  • Australia
  • Bites and Stings* / epidemiology
  • Humans
  • Incidence
  • Sharks*