Science Insider
12 August 2014
An international angling group should stop awarding weight-based world records for fish species threatened with extinction, researchers argue in a new study. The awards encourage the killing of the heaviest, most fecund fish, the scientists say, and should be replaced by conservation-friendlier records based on length.
Since 1939, the International Game Fish Association (IGFA) of Dania Beach, Florida, has been a leading record-keeper for recreational anglers, certifying who has caught the biggest fish. Today, it maintains records for some 1200 species.
In their study, published online before print in Marine Policy, the researchers found that 85 of those species are listed as either vulnerable, endangered, or critically endangered by the International Union for Conservation of Nature (IUCN) Red List. That’s a concern, the authors say, because although commercial fishers are sometimes barred from killing endangered species, recreational anglers often can. The researchers are particularly worried about the impact of trophy fishing, because removing the largest individuals can have a disproportionate impact on a population.
The most common method of certifying the size of landed fish is based on mass. But weighing large fish typically requires anglers to transport them to an official land-based weigh station—a method that makes it unlikely that the fish will survive. In many cases, this means the loss of egg-bearing females, because the females are larger than males in many species. So by killing big fish, the authors note, trophy anglers often remove individuals that are capable of producing the most high-quality larvae and helping depleted populations recover.