Thursday, April 7, 2011
April 7, 2011 : Mako Shark
The shortfin mako shark, Isurus oxyrinchus ("sharp nose"), is a large mackerel shark. Along with the closely related longfin mako (Isurus paucus) it is commonly referred to as a "mako shark".
In 1809, Constantine Rafinesque first described shortfin mako and coined the name Isurus oxyrinchus (IsurusMāori language, meaning either the shark or a shark tooth. It may have originated in a dialectal variation as it is similar to the common words for shark in a number of Polynesian languages— means "the same tail", oxyrinchus means "pointy snout"). "Mako" comes from the makō in the Kāi Tahu Māori dialect, mangō in other Māori dialects, "mago" in Samoan, ma'o in Tahitian, and mano in Hawaiian. The first written usage is in LeeKendall's & Grammar and vocabulary of the language of New Zealand (1820), which simply states "Máko; A certain fish". Richard Taylor's A leaf from the natural history of New Zealand (1848) is more elaborate: "Mako, the shark which has the tooth so highly prized by the Maoris".
The shortfin mako inhabits offshore temperate and tropical seas worldwide. The closely related longfin mako shark, Isurus paucus, is found in the Gulf Stream or warmer offshore waters.
It is a pelagic species that can be found from the surface down to depths of 150 meters (492 ft), normally far from land though occasionally closer to shore, around islands or inlets. One of only four known endothermic sharks, it is seldom found in waters colder than 16 °C (60.8 °F).
In the western Atlantic it can be found from Argentina and the Gulf of Mexico to Browns Bank off of Nova Scotia. In Canadian waters these sharks are neither abundant nor rare. Swordfish are a good indication of shortfin makos as the former is a source of food and prefers similar environmental conditions.
Shortfin makos travel long distances to seek prey or mates. In December 1998, a female tagged off California was captured in the central Pacific by a Japanese research vessel, meaning this fish traveled over 1,725 miles (2,776 km). Another swam 1,322 miles (2,128 km) in 37 days, averaging 36 miles (58 km) a day.
The shortfin mako's speed has been recorded at 50 kilometers per hour (31 mph) with bursts of up to 74 kilometers per hour (46 mph). They can leap approximate 9 meters (30 ft) high or higher in the air. Some scientists suggest that the biochemistry of shortfin mako can swim up to 100 kilometers per hour (62 mph). Scientists are in debate exactly how fast the shortfin mako shark can swim, as well as which particular species are actually the champion ocean swimmers. This high-leaping fish is sought as game worldwide. There are cases when an angry mako jumped into a boat after having been hooked.