Prionace glauca

Blue shark BSH
Characteristic features:

Dorsal surfaces indigo blue, often fading to dull grey after death. Fins without distinct markings, except for dusky ventral pectoral-fin tips. Ventral surfaces white.


Maximum size up to 383 cm TL; birth size 35–50 cm TL.


Circumglobal in all tropical and temperate waters; the most wide-ranging of sharks.


Oceanic and pelagic, from the surface to at least 1000 m depth; capable of large-scale migrations; usually well offshore but also occurs inshore where the continental shelf is narrow.


Feeds primarily on bony fish and cephalopods, but also small sharks and seabirds. Migrate seasonally to warmer waters in some areas; capable of undertaking trans-Atlantic migrations and from Northern to Southern Hemisphere; reported to frequently dive from the surface to more than 600 m depth. Size classes and sexes segregate. Potentially dangerous because of its persistence, but not very aggressive. Length at maturity is 207–220 cm TL and 182–220 cm TL for females and males respectively. Reproductive mode is viviparous with yolk-sac placenta. Females give birth to 4–135 (usually 15–30) pups after a gestation period of 9–12 months, and breed every 1 or 2 years.

Indonesian fisheries:

Very common bycatch of tuna and shark longline fisheries. Utilised for its fins (high value in adults), meat, skin jaws and cartilage. One of the most heavily fished sharks globally.

Similar species:

A distinctive species. Rarely misidentified as Isurus paucus.

Isurus paucus
Longfin mako

Isurus paucus

Isurus paucus is similar in having a similar pointed snout, dark-blue colouration and long pectoral fins, but differs in having a lunate caudal fin, with upper and lower lobes of similar length (vs. asymmetrical, with a much longer upper lobe and shorter lower lobe).

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