Fishing gear poses the greatest danger to young great whites off the West Coast of the U.S.

Fishing nets and lines kill more young white sharks living near Mexico and southern California than any other cause of death, a new study has found. A team of researchers led by ecologist John Benson used a relatively “untapped” but ubiquitous storehouse of data to help answer a question that scientists have about great whites (Carcharodon carcharias) as well as other sharks and marine species. “To our knowledge, our study is the first to provide an estimate of annual juvenile survival rate based on satellite tracking of individual sharks,” Benson, formerly at the Monterey Bay Aquarium in California and now with the University of Nebraska, told Mongabay in an email. The researchers published their work May 9 in the Journal of Applied Ecology. Fishing nets and lines kill more white shark young off the coast of California and Mexico than natural causes, the researchers found. Image by Rhett A. Butler/Mongabay. Shark scientists have been tracking the movements of white sharks with pop-up archival satellite, or PAT, tags for years. But until now, researchers hadn’t leveraged that information to figure out how many young sharks survive from year to year. “Because the PAT tags record detailed data on temperature and diving, it is possible to reconstruct the fate of the shark in the final minutes of each track,” Salvador Jorgensen, a biologist with the Monterey Bay Aquarium in California and co-author of the paper, said in a statement. “We’ve looked at these data for years and often noted when a tag…

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