Study Finds Catch-and-Release Sport Fishing Has Little Impact on Giant Trevally Population
VICTORIA, Seychelles — A long-running study of catch-and-release sport fishing at the Alphonse atoll has concluded that the practice has minimal impact on the population health of the giant trevally, one of the most sought-after species in the country’s blue economy.
Undertaken by an international team of biologists, conservationists and industry partners led by the Islands Conservation Society (ICS) and Blue Safari Seychelles, the “natural experiment” set out to investigate the effects of catch-and-release on the species. The Covid-19 pandemic, which shut down recreational fishing, offered researchers a rare opportunity to observe what happened to the species in the absence of total fishing pressure.
ICS conservation officer Jack Coupland, who is based on the Alphonse group of islands, said the research indicates that, while there are slight behavioural changes in the species to avoid anglers, the acoustic data shows no indication of impact on the population size, health, or breeding rates of the giant trevally. “With every additional season that we monitor the fly fishery, we can learn more about the impacts of hook shyness,” he noted.
The study is feeding into the Seychelles Fisheries Authority’s work on recreational angling regulations and the Seychelles Marine Spatial Plan. Blue Safari uses the data to inform its voluntary best-practice guidelines, and the ICS has long-term monitoring of all nine main target species at the atoll, including a tagging project for giant trevally.
