Fish
Shortfin Mako Shark
Isurus oxyrinchus · also called mako, blue pointer, bonito shark
The shortfin mako is the sports car of the shark world — a sleek, deep-blue, open-ocean hunter built for speed, able to burst at highway pace and to launch its whole body several metres into the air. It is also, increasingly, a shark in trouble.
Overview
Shortfin makos live in the warm and temperate open ocean of every sea, from the surface down to around 500 metres, ranging along continental shelves and far out into blue water. They are highly migratory, tracked crossing entire ocean basins, and they follow warm-water fronts and the movements of their fast-swimming prey. They are usually solitary.
Built for speed
Everything about the mako is tuned for fast pursuit:
- A rigid, streamlined body and a crescent tail on a narrow, keeled stalk — the same layout as a tuna.
- Regional endothermy. Heat-exchanging blood vessels keep the swimming muscles, gut, brain, and eyes warm, so the muscles work faster and the mako can chase prey efficiently in cool water.
- Long, thin, curved teeth visible even when the mouth is shut, ideal for gripping slippery, struggling fish.
- Drag-reducing skin covered in flexible, ridged denticles.
The result is the fastest shark, capable of running down tuna, bonito, and even swordfish, and of leaping up to six metres clear of the surface.
Reproduction
Makos are ovoviviparous: the embryos develop inside the female, and once their yolk is used up they feed on a stream of unfertilised eggs she keeps producing (oophagy). After a 15-to-18-month pregnancy she gives birth to a litter of pups, then does not breed again for two to three years. Females do not mature until around 18 to 21 years old. This extremely slow reproduction is the mako’s undoing under fishing pressure.
Threats and conservation
The shortfin mako is Endangered. It is one of the most heavily impacted pelagic sharks: taken as bycatch on longlines set for tuna and swordfish, targeted for its valuable meat and fins, and pursued as a big-game sport fish. Its slow life history means catches quickly outstrip the population’s ability to replace itself, and the North Atlantic stock in particular is severely overfished. In 2019 the species was listed on CITES Appendix II to regulate trade, and Atlantic fishery managers adopted a retention ban, requiring live makos to be released — measures aimed at giving one of the ocean’s most remarkable fish a chance to recover.
Shortfin Mako Shark: common questions
How fast is a shortfin mako shark?
It is the fastest shark and one of the fastest fish, with burst speeds usually cited at around 70 km/h and some estimates considerably higher over very short distances. It achieves this with a stiff, torpedo-shaped body, a nearly symmetrical crescent tail on a keeled tail stalk, and a smooth skin covered in specially shaped denticles that reduce drag. The speed lets it run down fast prey like tuna and bonito, and it also fuels the mako's spectacular leaps.
Is the mako shark warm-blooded?
Partly — it is "regionally endothermic," like its relatives the great white, porbeagle, and salmon shark and a few tunas. Networks of blood vessels called retia mirabilia trap the heat produced by the mako's red swimming muscles instead of losing it at the gills, keeping the core muscles, and separately the stomach, brain, and eyes, several degrees to over 10 °C warmer than the surrounding water. Warm muscle contracts faster and more powerfully, which is a big part of why the mako is so fast and can hunt in cool water.
Are shortfin makos dangerous to people?
They have the equipment to be — speed, size, and long, slender, hook-shaped teeth — but unprovoked attacks on humans are rare, because makos live in the open ocean away from where most people swim. Most recorded incidents involve spearfishers, anglers, and divers around hooked or baited sharks. A hooked mako is genuinely hazardous on a boat, as it will leap, thrash violently, and snap.
Why is the mako shark endangered?
Overfishing. Makos are caught in huge numbers on tuna and swordfish longlines as bycatch and are also targeted for their high-value meat and fins and prized as a sport fish. They reproduce very slowly — females do not breed until nearly 20, are pregnant for around 18 months, and then rest for a couple of years — so the population cannot keep pace with the catch. The North Atlantic stock is badly depleted, and in 2019 the species was uplisted to Endangered and its international trade brought under CITES control, with a retention ban introduced in the Atlantic.