The difference in diet may be attributed to the different types of mako sharks. They were categorized into two species in The most common is the shortfin mako, Isurus oxyrincus and the longfin or big-eye mako, Isurus paucus. The main difference in the two species of mako is their speed. The shortfinned mako is known for feeling the need for speed and its amazing leaps out of the ocean. They show great power and strength in hunting down their prey.
Their diet varies upon the waters they inhabit, however, since they are extremely active so are their appetites. During the gestation period, the young eat unfertilized eggs provided by the mother uterine cannibalism for nourishment. Female longfin mako sharks may swim to the coasts to give birth.
Although elusive, longfin mako sharks are not hidden from the global shark fin trade and are victims of bycatch in longline fisheries for pelagic fishes, such as yellowfin tuna , swordfish and sharks. Because they are less abundant and have low reproductive rates, longfin mako sharks are considered endangered. There is insufficient data on the number of longfin mako sharks captured by commercial fisheries.
The longfin mako shark got its name from its long pectoral fins that can be longer than its head, or 23 to 31 percent of its total body length. There has never been a reported attack by a longfin mako shark on a human. Formally described only in , the Longfin Mako is one of the least known lamnids. Its sheer size and wicked-looking teeth proclaim that the Longfin Mako is a formidable predator, able to tackle the largest and most powerful of fishes.
But can it really? The long, broad pectoral fins of the Longfin suggest that this species is slower and less active than its better-known relative, the Shortfin Mako Isurus oxyrinchus. This inference is further supported by the curious fact that, although it has the same heat-retaining modifications to the circulatory system as other lamnids, the Longfin Mako is unique among members of its family in that it does not seem to be warm-bodied.
The Longfin Mako's large eyes indicate that it is a deep-dwelling species and suggest that it may be a visual hunter. The former is supported by longline catches from off northern Cuba, as many Longfins are hooked at depths of to feet to metres but few at 60 to feet 18 to 90 metres ; the latter is supported by reports of higher catch rates on longlines with Cylume sticks chemical lights attached near the baits. The Longfin Mako's diet probably consists of schooling fishes and pelagic squids, some of which may be bioluminescent hence the increased catches on Cylume-equipped lines.
Unfortunately, no one knows for certain what Longfin Makos eat. The diet of the Shortfin Mako is relatively well known, including a wide variety of teleosts and cephalopods. Due to their similar size, shape, and dentition, it has long been assumed that the Longfin Mako eats more-or-less the same things as its short-finned congener, including large pelagic fishes such as Swordfish. A pound kilogram Shortfin Mako harpooned near Bimini, Bahamas, was found to contain a whole pound kilogram Swordfish.
Small individual Swordfish have also turned up as stomach contents in tunas, billfishes, and Blue Sharks Prionace glauca. But few predators are equipped to prey upon a full-grown swordfish. Fast-swimming, well-armed, and growing to a length of up to 15 feet 4. Swordfish have even been known to 'attack' deep-sea submersibles: in July , at a depth of 2, feet metres off the coast of Georgia, a pugilistic individual rammed the research submersible Alvin, wedging its bill firmly in the sub's superstructure; thus attached, the Swordfish was brought to the surface, where it was eaten by Woods Hole Oceanographic Institution scientists that evening.
Why would a Swordfish 'attack' a submersible or a Longfin Mako? Self-defense is a possibility, although the Swordfish could out-sprint any submersible and probably the Longfin Mako as well.
Besides, defensive attack presupposes that the punctured Longfin that began this essay was pursuing the Swordfish in a threatening manner. If that were the case, would not defensive slashes made with the Swordfish's bill have been concentrated around the shark's head rather than its abdomen and tail?
Why would a Longfin Mako and a Swordfish be in the same vicinity?
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