LED Fishing Nets Reduce Sea Turtle Deaths
EXETER, England — Using LEDs to illuminate fishing nets has been shown to be a cost-effective means of dramatically reducing the number of sea turtle deaths resulting from entanglement with nets.
Researchers from the University of Exeter and the Darwin Initiative executed the study in Sechura Bay, Peru. They found that attaching green LEDs to gillnets used by a small-scale fishery reduced the number of green turtle deaths by 64 percent without reducing the intended-catch size.
The LED-lit fishnet used at sea. Courtesy of the University of Exeter.
The team said it was the first time such lighting technology has been trialed in a working fishery. At a cost of £1.40 (about $2) for each LED light, the research showed that the cost of saving one turtle was £24, a sum that would be reduced if the method was rolled out at larger scale.
The researchers used 114 pairs of nets, each typically around 500 m in length. In each pair, one was illuminated with LEDs placed every 10 m along the gillnet floatline. The other net served as a control and was not illuminated.
The control nets caught 125 green turtles, while illuminated nets caught 62. The target catch of guitarfish was unaffected by the net illumination. The research team is now working with larger fisheries in Peru, and with different colored lights to see if the results can be repeated and applied with more critically endangered species.
The research was supported by ProDelphinus, a Peruvian nonprofit; the U.K. Government’s Darwin Initiative, and the University of Exeter, as well as the National Oceanic and Atmospheric Administration (NOAA).
"Bycatch is a complex, global issue that threatens the sustainability and resilience of our fishing communities, economies and ocean ecosystems," said Eileen Sobeck, assistant administrator for fisheries at NOAA, whose goals include the reduction of bycatch. “Through this work, we can better protect our natural resources."
The study is published in Marine Ecology Progress Series (doi: 10.3354/meps11610).
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