商業延繩捕魚器是鯊魚及魟魚的主要威脅之一。 科學家正測試一個能發出電磁場的新設備，放置在魚鉤周圍來驅除鯊魚及魟魚。 在測試期間，這些設備有助於將鯊魚的意外捕獲率降低 91%，魟魚的降低 71%。 但由於仍然存在電池及成本問題，這設計仍需要繼續改進。
Bycatch by commercial longline fishing is one of the main threat of sharks and rays. Scientists are testing on a new device that aims to create an electric field around fish hooks and repels sharks and rays. During the tests, these devices help reduce the bycatch rate by 91% for sharks and 71% for rays. however, more development is needed for this devise as there are still battery and cost issues.