REQUIEM SHARKS
CARCHARHINIDAE
Nurse Shark
Ginglymostoma cirratum
    Ecological Descriptors
Habitat Size Diet Behaviour Sex 

Ben, Dem
3m Cru, Ech, Mol, Pisc Noct I F
 
 
Description:
Adults: Sharks with small eyes, set behind the termination of the small mouth. Upper lip with
two barbels. Two dorsal fins, of nearly equal size, are set far back. Tail fin with a large and extended upper tail lobe and a small to indistinct lower lobe. The colour varies from gray to yellow-brown.
Juvenile: Body covered with small dark spots, occasionally also broad dark brown patches on light background.


Ecology
Found on continental and insular shelves. Solitary and sluggish fish, often encountered lying on the bottom. A nocturnal creature using amplullae of Lorenzini (electroreceptors) plus both tactile and chemoreceptors in barbels to detect benthic prey rather than eyesight. Feeding on benthic (bottom) invertebrates such as spiny lobsters, shrimps, crabs, sea urchins, squids, octopuses, snails and bivalves, and fishes like mullets, puffers and stingrays. Common over shallow sand flats, in channels, and around coral reefs; young may be found among prop roots of red mangroves.

Life Cycle:
Ovoviviparous, giving birth to live young, breeding twice annually (Biennial reproduction) . Mating season runs from late June to the end of July, where male sharks roam in search of a female, pinning the female by biting down on its pectoral fin when found. Once secured it extends its claspers (male sexual organ formed from the posterior portion of their pelvic fin acting as intromittent organs) ito the females cloaca depositing its sperm. During courtship, a pair, sometimes a triplet, of adults engage in  synchronized parallel swimming.
Gestation time is 5 to 6 months with 21 to 28 young in a litter, size at birth: 25 to 30 cm. Development of young in the uterus being sustained by a large supply of yolk, growing about 13cm and 2.3kg per year; fully mature at birth and are left to fend for themselves. It takes a total of 18 months for the female‚Äôs ovaries to produce another batch of eggs.  Age at maturity: Female: 15 to 20 years; Male: 10 to 15 years. Maximum age 25 years.





Blacktip Shark
Nurse Shark
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