10/26/2011

Lemon Shark

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The Lemon shark is a shark in the familyCarcharhinidae. It is known as the Lemon shark, because at some depth, light interaction with the local sea shark can give a tanned look pitted and yellow, like the size of a lemon.Lemon sharks are usually found in subtropical shallow waters near coral reefs, mangroves, closed bays, and the sounds and estuaries, while Lemon sharks do not seem to travel far into fresh water. They can be found in open water during migration, but in general they tend to stay along the continental and insular shelves. This species is known to groups based on size and sex and shape are seen in groups near fishing docks and piers at night to return to deeper water during the day.


Lemon sharks are named for their pale yellow to brown color on their dorsal (upper) side and a lighter yellow on their belly (lower) sides. The growth rate of the lemon shark is 0.54 cm per year. This species has two dorsal fins of similar size, the first is far back on the body behind the pectoral fins, second dorsal fin is located slightly forward of the origin of the anal fin. No interdorsal ridge. The ventral fin is slightly concave rear margins and the outer edge of the pectoral fin is slightly convex. Both the pelvic and pectoral fins are slightly curved. This shark has a blunt, short snout.

The Lemon shark is viviparous, meaning that women form a placenta-like connection to each of the developing fetus and eventually give birth to live free swimming puppies.Females and males reach sexual maturity at 6-7 years of age or at 2.4 m and 2.24 m respectively. Mating occurs in spring in shallow water, followed by a 10-12 month gestation period. Females return to shallow soils nurse from April to September to give birth to 4-17 pups measure between 60-65 cm external. Pups remain in the nursing grounds for several years, expanding their range as they grow.

Lemon sharks feed on bony fish, including: catfish, mullet, jacks, pill, porcupine fish, and Cowfish and guitar fish, stingrays, eagle rays, crabs and lobsters. Occasional lemon sharks also eat small sharks and seabirds. All the Sharks have electroreceptors concentrated in their heads, called the ampules of LorenziniThese receptors detect electrical pulses emitted by potential prey. Lemon sharks are bottom dwellers. They have poor eyesight and can not see to find their food, but are equipped with highly sensitive and accurate magnetic sensors in the nose.

Lemon sharks are both commercial and recreational hunting. U.S. longline goal lemon sharks and they are also caught as bycatch in the gillnet and pelagic. Their fins are sold for shark fin soup, and their skin is sold for leather. Lemon sharks are also sold for their meat.Population in the western North Atlantic and eastern Pacific are due to decreasing over-fishing. Lemon sharks are potentially dangerous to humans, but the International Shark Attack File only reported 10 unprovoked bites lemon sharks, all of which happened in Florida and the Caribbean.

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