AY Honors/Species Account/Isurus oxyrinchus

Isurus oxyrinchus

Shortfin Mako (Isurus oxyrinchus)

Where found: The shortfin mako inhabits offshore temperate and tropical seas worldwide. The closely related longfin mako shark, Isurus paucus, is found in the Gulf Stream or warmer offshore waters.

Description: The 'Shortfin Mako Shark (Isurus oxyrinchus—meaning "sharp nose") is a large mackerel shark. It is commonly referred to as the mako shark together with the longfin mako shark (Isurus paucus). The Shortfin Mako is a fairly large species of shark. An average adult specimen will measure around 3.2 meters in length and weigh from 60-135 kg. Females are larger than males. The largest "mako" taken (not verified between the two species) on hook-and-line was 505.8 kg. The Shortfin Mako is cylindrical in shape, with a vertically-elongated tail that assists its highly hydrodynamic lifestyle. This species' color is brilliant metallic blue dorsally and white ventrally, although coloration varies as the shark ages and increases in size. The line of demarcation between blue and white on the body is distinct. The underside of the snout and the area around the mouth are white. Larger specimens tend to possess darker color that extends onto parts of the body that are white in smaller individuals. The juvenile mako differs in that it has a clear blackish stain on the tip of the snout. The Longfin mako shark very much resembles the Shortfin, but has larger pectoral fins, dark rather than pale coloration around the mouth and larger eyes. The presence of only one lateral keel on the tail and the lack of lateral cusps on the teeth distinguish the makos from the closely related porbeagle sharks of the genus Lamna.