Scalloped Hammerhead

서식지: Seamounts, offshore islands, and current-swept drop-offs by day; disperses into deep water at night to hunt

범위: Circumglobal in warm temperate and tropical seas; the famous schools gather at Eastern Pacific seamounts, in the Red Sea, and off Japan

행동 특성: The schooling hammerhead. Hundreds of females may stack into slow-moving daytime schools around seamounts, thought to serve social and navigational functions between night feeding runs. Schools are famously shy of bubbles and noise: breath control and patience produce close passes, chasing produces an empty blue.

먹이: Fish, squid, and rays taken on nocturnal hunts in deep water

크기: 보통 2.5 m; 최대 기록 수심 4.0 m (total length; schooling females at seamounts typically run 2–3 m).

Tuck into the rocks down-current, slow your breathing or hold exhalations as the school passes, and never swim at the wall of sharks. Many operators brief a no-strobe or limited-strobe approach on first contact.

Critically Endangered from decades of fin-driven overfishing; listed on CITES Appendix II. Marine reserves at Cocos, Malpelo, and Galápagos protect key aggregations, though enforcement on the surrounding high seas remains the weak point.