‘Shortfin Mako’ Shark Under Threat: Study

2019 ias preliminary exam test series

The shortfin mako shark (Isurus oxyrinchus), also known as the blue pointer or bonito shark, is a large mackerel shark. It is commonly referred to as the mako shark, as is the longfin mako shark (Isurus paucus).

The shortfin mako is on record as the fastest-swimming shark, capable of bursts of speed up to 18.8 metres per second (68 km/h; 42 mph).

A new study shows that the fishing mortality rate of the shortfin mako in the western North Atlantic is considerably higher than previously estimated from catches reported by fishermen.

These data suggest that this major ocean apex predator is experiencing overfishing, raising serious concerns about whether the current levels of fishery catches in the North Atlantic are sustainable.

An unexpectedly high proportion, 30% of the 40 satellite tagged sharks, were captured in fisheries.

After modelling the probability that a mako shark would survive a year without being captured (a 72% chance) and calculating the fishing mortality rates, researchers determined that the rate at which shortfin makos were being killed in fisheries was actually 10 times higher than previously believed.

Globally, many shark species have seen significant declines in their numbers, with fisheries over-exploitation cited as a major cause.

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