Powerful, blunt‑snouted requiem shark easily recognised by dark vertical bars and blotches on a bluish‑grey to olive dorsum (most vivid in juveniles, fading in large adults). Body robust with pronounced keel on caudal peduncle and a low interdorsal ridge absent. First dorsal fin large, apex rounded; second dorsal and anal relatively small. Eyes large, circular; snout short and broad. Dentition: massive, deeply notched “saw‑tooth” cusps ideal for shearing turtle shell and bone. Adults commonly 3–4.5 m total length (TL) and 400–600 kg; maximum verified 5.5 m, > 1 000 kg. Sexes similar but females grow larger. Newborns 70–90 cm TL with high‑contrast striping.
Females attain larger size; males bear claspers.
Males 3.1 m; females 3.4 m (max 5.5 m)
250 – 600 kg
30–50 yr (vertebral radiocarbon)
Data deficient
Data deficient
Males ≈ 7 yr / 280 cm; females ≈ 8 yr / 320 cm
Biennial; mating late dry to early wet season in offshore waters
10 – 80 pups (mean ≈ 35); largest of any shark
Powerful, blunt‑snouted requiem shark easily recognised by dark vertical bars and blotches on a bluish‑grey to olive dorsum (most vivid in juveniles, fading in large adults). Body robust with pronounced keel on caudal peduncle and a low interdorsal ridge absent. First dorsal fin large, apex rounded; second dorsal and anal relatively small. Eyes large, circular; snout short and broad. Dentition: massive, deeply notched “saw‑tooth” cusps ideal for shearing turtle shell and bone. Adults commonly 3–4.5 m total length (TL) and 400–600 kg; maximum verified 5.5 m, > 1 000 kg. Sexes similar but females grow larger. Newborns 70–90 cm TL with high‑contrast striping.
Coastal to oceanic (surface – 1 000 m); patrols continental shelf edges, lagoons, estuary mouths, and oceanic islands. In Costa Rica frequent at Isla del Coco seamounts, Golfo Dulce canyon, and occasionally Nicoya & Papagayo bays. Juveniles prefer shallow bays and turbid river mouths.
Apex opportunistic predator and scavenger; diet spans sea turtles, dolphins, rays, bony fish, seabirds, crustaceans, carrion, and anthropogenic refuse.
Social Structure & Behaviour
Activity pattern: cathemeral; follows prey‑rich thermocline (50–150 m) by day, surfaces at night.
Group size: solitary or loose schools (5–50) around FADs, seamount plateaus and tuna schools.
Mating behaviour: suspected offshore; males bite female pectorals.
Site fidelity: seasonal return to Cocos–Galápagos corridor seamounts documented.
Communication: body‑arching and pectoral drop threat postures toward divers/competitors.
Nicknamed “garbage can of the sea” for swallowing tyres, cans, even license plates (none yet found in Cocos surveys).
Dark stripes fade with age—pattern acts as disruptive camouflage in juveniles.
Isotopic studies show seasonal commuting between Cocos and mainland turtle rookeries (Ostional, Naranjo).
Exhibits “yo‑yo” diving around dawn/dusk, possibly exploiting diel‑migrating prey.
Possesses the most diverse diet of any oceanic shark documented in Eastern Tropical Pacific.
