Hammerhead sharks are among the most threatened shark groups globally, facing bycatch in tuna longlines and targeted fishing for fins across their range.
Finning involves cutting fins from living sharks that then drown or are eaten by other sharks, causing prolonged suffering. Longline bycatch causes drowning when sharks cannot surface. Bycatch of live hammerheads released at sea have high post-release mortality. Hammer-shaped heads mean landing alongside boat hulls causes damage. Large aggregations are targeted by fishers causing population-level impacts.