shark shark species requiem shark belonging family common tropical subtropical waters western atlantic_ocean species generally inhabits coastal sand rubble habitats adults preferring deeper water juveniles small shark typically measuring long typical streamlined requiem shark shape long rounded snout large eyes small dorsal fin common comes characteristic black tip snout indistinct older individuals sharks feed primarily small bony fishes cephalopods turn fall prey larger sharks like members family exhibit viviparous mode reproduction developing embryos sustained connection females birth young late spring early summer annually gestation period months species known attack humans documented performing threat display divers moderate commercial recreational importance assessed species announced populations shark united_states proposed new conservation measures taxonomy phylogeny cuban naturalist published description shark natural later authors moved species genus type specimen male caught cuba based morphological data suggested shark sister relationship group containing shark shark proposed shark belongs group species including silky shark reef shark molecular analyses similarly shark phylogenetic relationships analysis found species basal member dna analysis indicated affinity shark shark shark found tropical western coast americas descended sharks experienced effects distribution habitat shark inhabits continental shelves eastern coast americas far north north_carolina far south southern brazil including bahamas gulf_of_mexico caribbean_sea frequent coastal waters beds sandy flats shell coral rubble species segregated size sex generally young sharks encountered shallow water adults prefer depths greater common sharks bight atlantic coast southern united_states migrate northward summer southward possibly offshore winter similar migration occurs sharks gulf_of_mexico description shark slender streamlined body long rounded snout large eyes developed skin defining outflow openings tooth rows occur upper lower jaws respectively teeth middle teeth triangular oblique edges upper teeth lower teeth pairs gill slits short measuring length dorsal fin base dorsal fin small somewhat shaped pointed apex short free rear tip origin lies free rear tips pectoral fins second dorsal fin relatively large half height ridge seen dorsal fins pectoral fins short tapered body covered overlapping dermal denticles bear seven longitudinal ridges young individuals leading marginal teeth coloration yellowish greenish gray brown white yellow distinctive dark tip snout obvious young sharks tips second dorsal fin upper caudal fin lobe lower caudal fin lobe dark sharks typically long weight maximum length weight record respectively biology ecology small fast swimming predator shark feeds primarily small bony fishes including octopus cephalopods competing bait speed allows food larger sharks caribbean reef shark species form large schools associated sharks demonstrate high degree juveniles adults documented returning local area year year sharks preyed larger sharks captives observed perform apparent threat display divers newly introduced members species display consists shark lowering pectoral fins jaws swimming exaggerated motion known parasites species include nemesis genera life history requiem sharks shark viviparous developing embryos exhaust supply yolk yolk sac develops connection mother provides united_states males thought reproduce year females reproduce year northeastern brazil female reproductive cycle short occur annually formation yolk occurs late summer immediately followed mating fall young born following spring summer events means reproductive cycle offset months populations northern gestation period variously estimated months northeastern brazil months southeastern united_states females typically birth litters pups shallow nursery areas coastal bays swamps known nursery area south_carolina relationship female size number young measure long female sharks grow slowly attain larger ultimate size longer lifespan males addition gulf_of_mexico sharks slower growing longer lived sexes mature fork length snout tip caudal fin fork corresponding ages years males years females gulf_of_mexico sexes mature fork length corresponding ages years males years females maximum lifespan calculated years years gulf_of_mexico human interactions shark implicated attack humans caution exercised begins perform threat display species regarded game fish offers respectable fight light tackle delicate fishing line regional commercial importance taken intentionally surface range significantly southwestern florida venezuela brazil meat sold dried large numbers sharks caught incidentally shrimp pose greater threat population sharks taken immature united_states fishing shark regulated fisheries management plan atlantic gulf_of_mexico sharks purposes commercial bag limits shark classified small coastal shark complex average sharks metric tons caught year united_states recent stock assessments conducted determined populations species atlantic gulf_of_mexico proposed separate sharks sharks year ban catch sharks atlantic contrast shark stocks northern brazil appear stable fishery data available caribbean assessed species globally
Blacknose shark