Threatened sharks and rays in the Mediterranean are more frequently caught in protected areas than in unprotected ones, according to a study published on Tuesday in the journal Nature Communications, which highlights the role of small fishing boats.
These species are among the most threatened by overfishing.
Although they are often accidentally caught in the nets of boats in search of other fish, the demand for their meat and fins has led to an estimated 71% decline in sharks and rays in the oceans since 1970. 90% of the world's fishing fleet is made up of small boats.
Their disappearance would have a direct link with these accidental catches.
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"Most people assume that it's the big trawlers that impact biodiversity, which is true," said study co-author Antonio Di Franco of the Sicily Marine Centre.
But there is "less research on the impact of small-scale fishing", he explains.
“We don't know the activity of the artisanal fishermen, we don't know how many nets they actually use, or where they fish.
Fishing doubled in protected areas
Italian researchers wanted to get a better idea of the status of species in the partially protected areas of the Mediterranean, which allow fishing with restrictions.
To do this, the research team photographed the catches of boats as they arrived in ports, and created a database covering small-scale fishing operations at 11 sites in France, Italy, Spain, in Croatia, Slovenia and Greece, in order to analyze them.
The team then used statistical models to show that catches of threatened species were higher in partially protected areas (517 specimens) than in areas with no protection (358).
24 endangered species of sharks and rays were caught.
An explanation is probably to be found in the fact that these species prefer coastal waters, where most artisanal fishermen prefer to operate.