Isurus

Isurus is a genus of predatory sharks in the family Lamnidae, commonly known as mako sharks. They are among the fastest and most agile predators in the open ocean, capable of high-speed bursts and long-distance short-distance endurance.

Two extant species are generally recognized: Isurus oxyrinchus, the shortfin mako, and Isurus paucus, the longfin mako. These species are distinguished by differences in fin morphology, body proportions, and geographic distribution, but both are streamlined, open-ocean hunters adapted to pelagic life.

Description

Mako sharks have a slender, torpedo-shaped body with a pointed snout, large eyes, and a crescent-shaped tail that provides powerful propulsion. They possess long, narrow pectoral fins and a tall first dorsal fin. Dorsal coloration is typically dark blue-gray on top with a white or pale underside. Shortfin makos can reach lengths of up to about 4 meters, while longfin makos are generally smaller.

Distribution and habitat

Isurus species are found in warm temperate and tropical oceans worldwide. They inhabit offshore, open-water environments but may occur near continental shelves. They are predominantly pelagic, ranging from near the surface to several hundred meters deep, with occasional deeper dives.

Diet and behavior

As apex predators, mako sharks feed on pelagic fishes such as tuna, swordfish, and marlin, as well as squid. They are known for rapid acceleration, skilled pursuit of fast prey, and occasional surface leaps.

Reproduction

Isurus species are viviparous, with internal fertilization and placental connections. Gestation lasts roughly 12–18 months, after which females give birth to litters typically in the range of a few to a couple dozen pups. Birth size is usually around 60–100 cm for the young.

Conservation

Mako sharks face fishing pressures from both commercial and recreational fisheries, and their fins are valued in some markets. Populations have declined in certain regions, leading to regional management measures and ongoing conservation concerns, though status and protections vary by area.