Researchers in Brazil say they've found a way to curb shark attacks without culling sharks—which, if true, is good news for conservationists who oppose lethal means of controlling sharks in South Africa and Australia, LiveScience reports. The Brazilian program was tried off and on for nearly 10 years after shark attacks spiked in 1992, possibly because a newly constructed port complex upset their habitat. Instead of following the South African and Australian method of using gill nets—which often suffocate sharks to death and ensnare other marine animals—state officials opted to capture sharks, take them to deep waters, and let them go.
They did this by deploying fishing lines that hooked sharks (and other sea life) along a 12-mile sweep of shoreline in northeastern Brazil, Science reports. A crew often checked the lines for possibly dangerous sharks like black tips, tiger sharks, and bull sharks, and motored them away in saltwater tanks on a boat. Over 73 months, they caught 1,121 animals, 7% of which were shark species worth relocating; 60% of them survived the process, as did 78% of other marine life that was caught and released. The tactic may not work everywhere, researchers admit, but it did reduce shark attacks around the city of Recife, Brazil, from 0.289 per month to 0.014 per month. What's more, reports Mother Nature Network, the study authors write that relocated sharks "did not move back to nearshore waters off Recife ... and did not experience post-release mortality." (Read about a surge of great whites near a Cape Cod town.)