Endangered sharks, rays caught in protected Med areas: study
Endangered sharks, rays and rays in the Mediterranean are more likely to be caught in protected than in unprotected areas, according to research published Tuesday that highlights the need for better protection of critically endangered species.
The three types of cartilaginous fish are among the most threatened by overfishing.
Although they are often landed as bycatch — or caught in nets from boats landing other species — demand for their fins and meat has led to an estimated 71 percent decline in ocean sharks and rays since 1970.
Although they are among the oldest marine species on Earth, their slow growth rate and late maturity means that a third of cartilaginous fish are categorized as in danger of extinction by the International Union for Conservation of Nature (IUCN).
While dozens of countries have banned large-scale fishing for endangered shark, ray and ray species, the true global catch figures are likely to be vastly underestimated, as 90 percent of the world’s fishing fleet is made up of small-scale boats.
Researchers in Italy wanted to get a better idea of how species are doing in the partially protected areas of the Mediterranean, which allow some fisheries with restrictions.
They used photo samples and image analysis to build a database of more than 1,200 small-scale fishing activities in 11 locations in France, Italy, Spain, Croatia, Slovenia and Greece.
The team then used statistical models to show that catches of endangered species were higher in partially protected areas than in areas without any protection.
“People assume that large-scale trawlers affect biodiversity, which is true and there is a lot of evidence for that,” said study co-author Antonio Di Franco of the Sicily Marine Center.
“There has been less research on the impact of small-scale fishing and our research shows there is potential.”
The team found that catches they analyzed in partially protected areas landed 24 species of sharks, rays and rays, more than a third of which are in danger of extinction.
This is likely due in part to the species’ preference for coastal waters, where most small-scale fisheries prefer.
“We don’t know the activity of small-scale fishing in general, we don’t know how many nets they actually fish or where they fish,” Di Franco said.
In total, 517 cartilaginous fish were caught in the partially protected areas studied, compared to 358 in non-protected areas.
In terms of mass, the weight of shark, ray or ray species caught in partially protected areas was about double that in non-protected areas.
More than 100 countries have committed to increasing the number of protected oceans worldwide to 30 percent by 2030.
Di Franco said there are a number of steps countries can take to help endangered species, including equipping smaller fishing boats with GPS trackers and merging protected areas so the species can more easily change habitats.
“Protected areas are a great potential benefit for biodiversity, but the point is to look at management,” he told AFP.
“But often countries don’t have the capacity to properly manage stocks.”
Two-thirds of species in the global shark fin trade are at risk of extinction
© 2022 AFP
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