Built like a missile: a metallic blue back, a knife-edge boundary to the white belly, a conical pointed snout and a stiff crescent tail on a narrow keel. Adults run 2.5 to 3.2 m (8 to 10.5 ft), with exceptional females at 3.8 m (12.5 ft) and over 500 kg (1,100 lb). It is the fastest shark in the sea, credited with bursts around 70 km/h (43 mph), and it can clear the surface by several meters.
The speed comes from being warm. This shark runs a counter-current heat exchanger in its blood vessels that traps the heat generated by swimming muscle instead of losing it through the gills, keeping the muscle, the gut and the eyes several degrees above the surrounding sea. Warm muscle contracts faster and recovers faster, and that is the difference between a shark that cruises and one that can run down a tuna - which is exactly what this animal eats.
It is an open-ocean animal that only occasionally comes near a reef, and encounters underwater are exceptional. Where it is met, it is fast, direct and shows no caution at all.
The name comes from Maori, in which mako means shark or shark tooth, and it is one of very few Polynesian words to enter scientific usage. The species is Endangered: high-value meat and fins, a fifteen-year wait to maturity, and a three-year breeding cycle add up the way they always do.
The genus. Isurus Rafinesque 1810 - ísos (equal) + urus (tail). ETYFish
The species. Isurus oxyrinchus Rafinesque 1810 - sharp-snouted. ETYFish
- metallic blue back with a knife-edge boundary to the white belly
- conical pointed snout and a stiff crescent tail on a keel
- large black eye, no markings on the fins
- in open ocean, rarely near reef
