Pelagic thresher sharks visit the Monad Shoal seamount in the Philippines so that cleaner wrasse eat the parasites that infest their skin and gills. Within this zone, they are well protected because the local economy near Malupascua Island receives 80% of its income from dive tourism. But when the sharks venture further afield, they are at risk from fishing lines set for smaller fish, and from capture for their meat, fins, skin, and liver oil. Combined with the animals’ slow reproduction, these pressures mean that numbers of pelagic thresher sharks are declining. For that reason, scientists have been monitoring the sharks’ whereabouts using acoustic trackers. Journalist and photographer Louise Murray tells the full story in the June 2019 issue of Physics World.
Tracking pelagic thresher sharks
