The Longfin Mako Shark is given it’s name due to its especially long pectoral fins. These fins are often just as long as (or even longer) than their head. Like its direct relation, The Shortfin Mako Shark, the Longfin is most commonly set apart by its huge eyes and long, knife-edged teeth that project from its glorious mouth.
Longfin Mako Shark Description
The Longfin Mako Shark (Isurus paucus) is a species of mackerel shark (Lamnidae family). It appears in temperate and tropical waters around the world. A relatively rare species that was lumped together with the name Mako after its relative, the Shortfin Mako Shark (I. oxyrinchus).
It has a maximum length of 4.3m (14ft) and a slimmer physique as well as longer and wider pectoral fins. This indicates that it is a slower and less active swimmer than its relative. It is a pelagic species that occurs in very deep waters and has been recorded from a depth of 220m. The Longfin Mako Shark is a predator that feeds on small, bony fish and cephalopods.
It is uncertain whether this shark is able to raise his body temperature above that of surrounding water. The long-finned mako has endothermic countercurrents (vascular heat exchangers) in the body muscles. These are also in the eyes, brain and intestines, like other sharks. However, the degree of temperature increase it achieves under ambient conditions has not been measured.
The Longfin Mako Shark is the largest of the two Mako. It is also one of the largest species in its family (second to the Great White Shark). It grows 2.5 m long, weighs up to 70 kg in females and becomes twice as large in males. They are slender, with a long pointed snout. The large eyes have a lack of a nicking membrane on the protective third eyelid. The largest recorded Longfin Mako Shark was a 4.3-meter female caught in February 1984 off Pompano Beach, Florida.
The Longfin Mako Shark belongs to the five members of the family Lamnidae, to which also the Short Fin Mako, the great white shark, the porbeagle and the salmon shark belong. Like other mackerel sharks, it has a crescent-shaped tail with a pronounced keel and retention physiology (retiminabilia). The size and appearance of the Longfin Mako Shark is similar to that of its sister species, the Short Fin Mako, but it grows longer (up to 4 meters) and has a slimmer stature with a longer and wider pectoral fin.
The longfin mako shark teeth are large with razor-shaped edges and secondary cuspids. The outermost teeth of the lower jaw stick out of the mouth. Twelve to 13 rows of teeth occur on both sides of the maxilla. The longfin mako shark teeth have 11 to 13 rows on each side of the mandible. The pectoral fin is long, with a straight front edge and broad tip.
The denticles of the dermal teeth are elliptical, long and wide. Three to seven horizontal ridges lead to a serrated posterior margin. The tail fin is crescent-shaped, with a small notch at the top of the upper lobe. The second dorsal and anal fin are tiny. The colouring is dark blue, grey-black or white. The caudal stems are broad and have a strong keel.
The first dorsal fin has a large rounded crown and is located just below the pectoral muscles. The gills are slit so long that they reach to the top of the head.
In this species, reproduction is aplacental (viviparous), which means that embryos from eggs hatch in the uterus. In a later stage of development, the unborn cubs feed on non-viable eggs from the mother (oophagy). The litter sizes can be between two and up to eight pups.
This Mako inhabits the upper Mesopelagic during the day and ventures into the Epipelagic at night. They are most abundant in the waters of the Western Atlantic and Gulf Streams in northern Cuba. They are also found in southeast Florida, the Central Pacific, the Phoenix Islands and northern Hawaii.
It is thought to migrate throughout its tropical oceanic range, although specific movement patterns have not been identified. The inhabitants of the open ocean live at a depth of 110 to 220 meters below the epipelagic-mesopelagic boundary, although they have also been observed at depths below 90 meters.
Longfin Mako Shark Conservation
The International Union for the Conservation of Nature (IUCN) classifies Longfin Mako Sharks as critically endangered due to their rarity, low reproduction rates, persistent by-catches and mortality. From 2019, the IUCN will list the Longfin Mako Shark and the Shortfin Mako Shark as critically endangered. Its commercial value is limited as its meat and fins are of lower quality than other pelagic sharks and it is caught in small quantities throughout its range.
They are caught in Cuban longline fishery off the north coast of Cuba and in the Japanese tropical pelagic longline fishing, which is offered for sale in Tokyo. Its flesh is used as fresh, frozen or dried salt for human consumption. In addition, some longline species are caught with hooks and anchored gillnets.
So, is the longfin mako shark endangered? Low fertility, late sexual maturity, low frequency and increasing pressure from fisheries in the oceans have placed this species under special protection and it is listed as vulnerable on the IUCN Red List of Threatened Species (Appendix I), Appendix I of UNCLOS (CMS) and the Memorandum of Understanding on Migratory Sharks (Appendix II, CMS).
Despite this need, few conservation measures have been taken for the Longfin Mako Shark. The species is caught in the tropical pelagic longline fishery on tuna, swordfish and sharks in anchored gill nets, hooklines and other oceanic fisheries in its range. The meat is considered of inferior quality and of little commercial value, although the fins are valuable and have a price, and specimens caught without fins and their carcasses are disposed of at sea.
Longfin Mako Shark Diet
The diet of the Longfin Mako Shark is known to include a variety of teleosts, bony fish and cephalopods. They also feed on pelagic cuttlefish and school fish. The main prey of this species is fish and squid. However, they will also eat tuna, bonito, mackerel, swordfish, and other fish species. While it’s less likely, they will sometimes munch on ocean birds, other smaller sharks, turtles, and small porpoises.
Because they’re very fast and aggressive predators, they have an advanced metabolism, and must feed almost constantly. In order to survive and remain healthy, they must eat at least 3% of their total body weight. For a Mako weighing 150 lbs, that’s roughly 4.5 lbs of fish per day.