shark shark species sharks family shark found pacific_ocean continental shelves slopes submarine dwelling nature generally inhabits cool waters deep frequently enters shallower water areas california dark colored shark grows long small dorsal fins positioned far body anal fin characterized dense covering like dermal denticles common active shark rests day deeper offshore waters performs migration shallower waters dusk individual sharks small home range tend remain given local area species variety bony fishes cephalopods moves slowly use capture prey viviparous females producing sizable litters shark known dangerous humans minimal economic value caught incidentally commercial fisheries expanding potentially threaten population assessed species taxonomy austrian described shark new species separate publications brief german account volume der der detailed english account volume named shark honor sharks continually sharks referred scientific literature species original hawaii lost designated long male bay new_zealand new type specimen common names species include cook shark shark description shark cylindrical body adults markedly juveniles short moderately flattened head nostrils placed far apart preceded small flaps skin tiny positioned eyes lack membranes mouth forms broad arch short furrows corners tooth rows upper lower jaws respectively knife like teeth strongly angled main flanked smaller lateral absent young sharks pairs gill slits fifth pair longest lateral line runs body conspicuous pectoral fins short pelvic fins relatively large long bases dorsal fin small originates level pelvic fin origins second dorsal fin similar positioned close anal fin absent stout caudal lacks depressions caudal fin origins caudal fin longer upper lobe notch trailing margin indistinct lower lobe skin dense uniform covering non overlapping dermal denticles measuring fused shark like strong ridges running central spine star shaped base denticles beneath snout fine adults shark plain brown gray black trailing margins fins underside paler obviously snout mouth reach length maximum recorded weight long female distribution habitat shark widely distributed pacific_ocean western central pacific reported japan taiwan victoria queensland australia new_zealand islands hawaii possibly eastern pacific known occur oregon el_salvador including peru chile species generally uncommon exception california sharks sexes abundant year favoring cooler temperatures shark found depths particularly tropics recorded occur deeper possibly hand higher latitudes frequently enters shallow waters example consistently found depths individual captured water deep shark inhabits continental shelves slopes close found inside submarine close walls prefers areas muddy sandy substrate tolerant low dissolved oxygen levels allowing inhabit oceanic basins inaccessible sharks biology ecology shark slow swimmer observed sea floor tracking study found species exhibits strong migration patterns sharks inactive day resting refuge areas located near sea floor deep offshore waters active dusk swimming coast head canyon rising water column upward movement likely related feeding schooling fishes individual sharks seldom local area small home ranges km2 sharks regularly form number thirty size structure shark mouth suggests uses capture prey species feeds variety benthic bony fishes including herring fishes including young sharks ghost egg cases squid including squid consumed young sharks fall prey shark adults likely face threats reproduction species viviparous young sustained yolk known record pregnant female embryos ranks largest known litters shark young probably long birth length sexual maturity precisely determined thought males females human interactions interactions divers shark humans contact fleeing closely approached susceptible incidental capture commercial line gear little commercial value meat soft poorly regarded assessed shark citing known distribution continuing expansion fisheries
Prickly shark