A disturbing new report has revealed that turtles are being caught in their tens of thousands off the coast of South America as bycatch from small fisheries.
The study, published in the journal Fisheries Research, has put the numbers at an estimated 46,000 turtles caught a year, with 16,000 of those resulting in deaths, though the researchers suspect the numbers are actually much higher.
The team from the University of Exeter’s Marine Turtle Research Group surveyed 43 harbors in Ecuador, Peru, and Chile and discovered that small-scale fishing vessels using gillnets are comparable to fishing on an industrial scale when it comes to threatening unintended species.
"People worry about industrial fisheries but a real concern that people are waking up to is small-scale fisheries," said Professor Brendan Godley, from Exeter’s Centre for Ecology and Conservation, in a statement.
"These are small vessels but they exist in such huge numbers that they can have a massive impact on ecosystems."
Gillnet fishing is a method used both on a large commercial scale and by small fishing vessels, where a vertical net is dropped into the ocean to catch an intended target, but often ends up catching much more. This method is highly inaccurate and dangerous to many larger marine creatures that get caught in the nets. The most famous example, of course, is the plight of the vaquita, of which there is now thought to be just 12 in the world, due to China's insatiable appetite for totoaba fish, which are caught using gillnets in the Gulf of California.
The team surveyed the number of sea turtles caught as bycatch at 43 ports and fisheries across the three nations in order to gauge the impact of the small-scale fishing in particular on sea turtles. Both the leatherback turtle, which is critically endangered in the Pacific, and the hawksbill turtle, which is critically endangered everywhere, are the unfortunate victims of this rapidly growing bycatch issue.
The survey results showed an estimated 46,478 turtles are caught a year, the majority in Ecuador, which was responsible for around 40,480, whereas Peru caught around 5,828, and Chile 170 turtles.
The researchers’ aim is to help form a way of managing both the ecosystems of the species threatened and the livelihoods of the millions of people who rely on the fisheries as a source of food and employment. This study is an important step in highlighting where the situation is most critical and new management schemes should be concentrated.
"This work highlights the importance and the benefits of our approach of engaging with fishers,” said co-author Dr Joanna Alfaro. "Our goal is to develop fisheries that are sustainable for small-scale fishing communities and the species with which they interact."