Nurse Sharks | Marineland

Why is it called a Nurse Shark? It is because of the way it sucks up its prey, reminiscent of the suckling sound of human babies. Another of its distinctive features is that it sleeps for 20 hours on the sandy bottom, hence its other name of Sleeper Shark. Thanks to muscles located near its gills, this shark is able to circulate water over its gills so that it does not need to swim to breathe, unlike most other sharks. It averages 2.5 metres in length and can reach up to 4.5 metres, making it one of the largest sharks, although it is a far cry from the 18 metres of the Whale Shark.

The Nurse Shark (Ginglymostoma cirratum) lives in tropical coastal waters in the Atlantic, Pacific and Indian oceans. Although it can sometimes be found at depths of over 100 metres, the Nurse Shark lives at depths of between 15 and 25 metres most of the time. It is easily recognisable by its grey or brown colouring, its flat head and its small eyes. It has a very long tail, two almost identical dorsal fins and a muzzle equipped with a pair of sensory barbels or feelers. Its highly developed sense of smell enables it to find prey that is camouflaged on the seabed.

Nurse sharks feed mainly on crustaceans, small fish, molluscs, squid, rays, lobsters and sometimes sea urchins and soft corals. It hunts alone at night. It is a very useful predator that helps control populations of several marine organisms.

It has a gestation period of 5-6 months and the species is ovoviviparous, meaning that the eggs develop in the female's uterus and hatch there before delivery. Nurse sharks have litters of about 30 baby sharks. Its numbers are steadily and dangerously declining and it is now classified as a vulnerable species (VU) on the IUCN Red List of Endangered Species (2019).