LED lighting nets can drastically reduce marine bycatch and improve fishing efficiency

The study's authors include Jesse Senko, an assistant research professor at Arizona State University; Hoyt Peckham, director of small-scale fisheries at the Wildlife Conservation Society; Daniel Aguilar-Ramirez, a fisheries biologist at the National Institute of Fisheries and Aquaculture in Mexico; and a fisheries ecologist with the NOAA Fisheries Division. John Wang.

Gillnets are one of the most widely used fishing gear along the coasts of the world's oceans, but they also often catch other animals that are not targeted by fishermen. These animals include endangered, threatened and protected species such as sharks, turtles, marine mammals and seabirds, but also other fish species and non-marketable juvenile target species. These animals are often dead, wounded and thrown into the sea. The accidental capture of non-target species in coastal gillnet fisheries -- known as "bycatch" -- has contributed to the decline of endangered species worldwide, while also affecting coastal ecosystems.

Over the past decade, lighting gillnets with LED lights has become an effective tool for reducing bycatch of endangered sea turtles in coastal gillnet fisheries. However, the impact of net lighting on other vulnerable species, total fishery by-catch and the efficiency of fishery operations has never been studied.

Researchers installed green LED lights every 10 meters on gillnets along the Pacific coast of Baja California Sur, Mexico, and were also surprised to find that the lighting nets nearly eliminated sharks, rays due to global declines due to by-catch and illegal fishing. and by-catch of rays, an ancient group of animals.

In addition, the illuminated net reduces the time fishermen spend retrieving and untying their nets by 57%, making the technology attractive to fishermen looking to increase efficiency without worrying about by-catch. This is because fishermen need to remove fewer entangled animals in the lighted nets, including a considerably smaller number of turtles, sharks, rays, rays, squid and small fish, which are time consuming, difficult and even difficult to remove from the nets. is dangerous. In practice, this means that fishermen can save more than an hour per trip when fishing with lighted nets, which also helps improve the quality of their catch.

Jesse Senko from Arizona State University, the study's lead author of the paper, noted: "These results demonstrate the potential benefits of lighting nets well beyond the reach of sea turtles, while demonstrating that similar coastal gillnets are found in oceans around the world. In fisheries, lighting nets hold great promise to mitigate discarded by-catch."

Co-author Hoyt Peckham, director of small-scale fisheries at the Wildlife Conservation Society, said: "Gillnets are ubiquitous because they are inexpensive and catch everything that passes through them. This work is exciting because it provides A practical solution has been developed to increase the selectivity of gillnets and avoid their bycatch. Emerging technologies should help us to incorporate this lighting into gillnet materials, making adoption of this solution a change for fishermen It's a no-brainer."

"Making life easier for fishermen by reducing the time it takes to unwrap by-catch is similar to reducing the amount of fish in the net," said John Wang, a fisheries ecologist at the NOAA Fisheries Service's Pacific Islands Fisheries Science Center in Honolulu and co-author of the study. The by-catch biomass is equally important. It is important that fishermen know there are tangible benefits to them. This is critical to the adoption of such techniques in the fishing industry.”

The World Wildlife Fund (WCS) is working in many coastal countries to reduce bycatch of iconic megafauna in gillnet fisheries such as dolphins, sharks and rays. To date, however, technical solutions to reduce by-catch are very limited, and allowing fishers to continue harvesting the species they seek often has important impacts on livelihoods and food security. This work provides a possible means of protecting the last stronghold of threatened megafauna around the world and will be further explored as part of WCS' global marine conservation efforts.