AY Honors/Species Account/Negaprion brevirostris

Template:Taxobox Template:Portal The lemon shark, Negaprion brevirostris, is a shark that belongs to the family Carcharhinidae that can grow Template:Convert long.

Distribution and habitat

The lemon shark is found mainly along the subtropical and tropical parts of the Atlantic and Pacific coasts of North and South America, and around Pacific Islands. The longest lemon shark recorded was 13 ft long, but they are usually 8 to Template:Convert. They like tropical water, and like to stay at moderate depths. Lemon sharks are often accompanied by remoras.

Reproduction

Lemon sharks are viviparous, females giving birth to between 4 and 17 young every other year in warm and shallow lagoons. The young have to fend for themselves and remain in shallow water near mangroves until they grow larger. With increasing size, the sharks venture further away from their birth place. At maturity at a size of 1.5 to 2 m and an age of 12 to 15 years, they leave shallow water and move into deeper waters offshore. However, little is known of this life stage. Maximum recorded length and weight is 340 cm and 183 kg.

Recent work in genetics by Kevin Feldheim and Samuel 'Doc' Gruber may suggest that adult sharks move over hundreds of km to mate, or populations far apart may have been separated in recent time. Further research in this area would be of immense importance for the understanding of the lemon shark's breeding behaviour and ecology.

Importance to humans

Lemon sharks are a popular choice for study by scientists as they survive well in captivity, unlike many other species such as the great white, which die in captivity because of food refusal. The species is the best known of all sharks in terms of behaviour and ecology, mainly thanks to the enormous effort of Samuel Gruber at the University of Miami who has been studying the lemon shark both in the field and in the laboratory since 1967. The population around the Bimini Islands in the western Bahamas, where Gruber's field station, Bimini Biological Field Station, is situated, is probably the best known of all shark populations. As of 2007, it is experiencing a severe population decline and may disappear altogether due to destruction of the mangroves for construction of a golf resort. There have been 22 known lemon shark attacks since 1580 with 7 deaths.

Electroreceptors

All sharks have electroreceptors concentrated in their heads called the Ampullae of Lorenzini. These receptors detect electrical pulses emitted by potential prey. Lemon sharks are bottom dwellers but have very poor eyesight and cannot see well to find their food. However, they are equipped with extremely sensitive and accurate magnetic sensors in the nose.

See also

• List of sharks

References

• Template:IUCN2006 Database entry includes justification for why this species is near threatened
• Template:ITIS
• Template:FishBase species
• Washington Post, 2005, Aug. 22nd: "Scientists Fear Oceans on the Cusp Of a Wave of Marine Extinctions"

External links

• Lemon shark facts and pictures