Mako Shark
There are two extant species of Mako sharks (genus Isurus): the Shortfin Mako (Isurus oxyrinchus) and the Longfin Mako (Isurus paucus). The shortfin mako – also known as the blue pointer or bonito shark – is more common compared to the more elusive Longfin Mako. Mako sharks belong to the order of Lamniformes that include Thresher sharks, Basking shark, Megamouth shark, Sand Tiger sharks and the Great White shark. The Mako shark is also known to be the fastest of all sharks.
Mako shark anatomy and appearance
Mako sharks can be recognized by their stream-lined bodies and conical snouts. Adults can grow to be three to four meters long, weighing around 570 kilograms. Mako sharks have heat exchange circulatory systems that keep their bodies warmer in cold waters, making them one of the few endothermic sharks. Their warm blooded physiology allows them to move at quicker speeds. Makos have larger eyes compared to other species, and have better eyesight. They have a tapetum lucidum, which is a structure that is located behind the retina and is made up of reflective crystals. This enables them to reflect light through the retina, which can be useful for hunting in darker, deeper waters. Makos also have nictitating membranes, which are translucent eyelids that protect the sharks’ eyes. They have long gills and slender teeth that lack cusps. The teeth on the lower jaw are exposed even when the jaws are closed. Mako sharks’ caudal fins are crescent-shaped, and they have prominent caudal keels. Their bodies are a dark metallic gray/blue in the dorsal area, and are white ventrally. The transition in color from the dorsal to ventral area is distinct. Juvenile mako sharks can be identified by the black coloration on the tips of their snouts.
There are some differences between Shortfin and Longfin Mako sharks. Longfin Mako sharks’ eyes are distinctly larger than their shortfin relatives, and tend to have slimmer bodies. While Shortfin Makos are white around the snout, Longfin Makos tend to have a darker coloration in those areas. As their name suggests, they have exceptionally long, broad-tipped pectoral fins that grow to be longer than their heads. Scientists suspect that the differences in anatomy between the two species are related to the fact that Longfin Makos are slower and less active than the Shortfin Makos.
Mako shark habitat
Mako sharks are found in tropical and temperate waters of around 16 to 22 degrees Celsius. They can be found in a wide range of locations, including areas around Chile, California, the Gulf of Mexico, the Caribbean Sea, and throughout the Indo-Pacific from East Africa to Hawaii. As pelagic species, they tend to prefer offshore locations at depths of 150 meters, although juvenile makos have been found in coastal waters. Mako sharks are highly migratory and can travel extremely long distances. Their migrations can be associated with water temperature changes and the presence and movement of prey.
Mako shark diet
Mako sharks have few natural predators but hunt a variety of prey. They tend to feed on bony fish such as tuna and swordfish, as well as cephalopods like squid. They also have been known to hunt mackerel, smaller sharks like the Blue shark (Prionace glauca), sea turtles, and some marine mammals. Occasionally, adult mako sharks will also prey on juvenile makos, although they are not generally known to be cannibalistic. During the hunting process, mako sharks use their exceptional eyesight, agility, and speed to find, outpace, and catch their prey.
Mako shark population
Mako sharks have an average lifespan of thirty years. Males mature at around eight years old (at a length of 1.9 meters), while females mature later at around eighteen years old (at a length of 2.8 meters). They have a three year reproductive cycle, and the gestation period is fifteen to eighteen months. Mako sharks are ovoviviparous, which means that embryos in the uterus receive nourishment from yolk sacs rather than a placenta like most mammals. They also feed by oophagy; once hatched in the uterus, they ingest unfertilized or less developed eggs. Makos give birth to live pups, and the litter size can range from 2-25 pups, although they tend to be smaller (4-6 pups). The size at birth is around 60-80 centimeters.
Mako shark conservation
Both species – the Shortfin and Longfin Mako – were assessed and listed as Endangered on the IUCN Red List of Threatened Species in 2018. Mako sharks have been experiencing a decline in their population size. This is largely due to the global shark fin trade, as well as demand for shortfin mako flesh. Since makos live in places where commercially valuable fish (such as tuna and swordfish) are found, they also tend to get caught as by-catch. As apex predators, mako sharks play essential roles in their ecosystems.
In the United States, Mako sharks are also targeted in shark fishing tournaments. This has led to a number of conservation groups starting petitions and seeking support both through the public and local government agencies to oversee and restrict shark fishing tournaments.
Other interesting facts
The Shortfin Mako shark is known as one of the fastest pelagic sharks. While it usually travels 50 kph, it is capable of reaching top speeds of 70 kph in short bursts. Mako sharks can also leap out of the water, reaching heights of up to 9 meters. Scientists speculate that makos make these jumps as a hunting technique that helps them catch their prey.
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