Lemon shark
From Wikipedia, the free encyclopedia
| Lemon shark | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||||
| Conservation status | ||||||||||||||||
| Scientific classification | ||||||||||||||||
|
||||||||||||||||
| Binomial name | ||||||||||||||||
| Negaprion brevirostris (Poey, 1868) |
||||||||||||||||
 Range (in blue)
|
The lemon shark, Negaprion brevirostris, is a shark belonging to the family Carcharhinidae that can grow 10 feet long (3 meters)[1].
Contents |
[edit] Distribution and habitat
The lemon shark is found mainly along the subtropical and tropical parts of the Atlantic coast of North and South America. This species can be found as well in Pacific islands of Polynesia - French Polynesia - Tahiti, the Cook Islands, and Tonga. The longest lemon shark recorded was 12 ft long, but they are usually 8 to 10 ft. They like tropical water, and like to stay at moderate depths.
[edit] 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. They can be extremely aggressive and protective if young sharks are around.[1]
Recent work in genetics by Drs Kevin Feldheim, Sonny Gruber and Mary Ashley 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.
[edit] 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 shark, which dies 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 Dr. 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 Dr 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 lemon shark attacks since 1580 with no deaths.
[edit] The Magnetic Field
All sharks have magnetic sensors in their nose. It helps them to find food and locate places, to find their breeding place, to find where they were born, etc. Lemon sharks however have very poor eyesight. The cannot see well to find their food, and they are bottom dwellers, so they make up for it by having an extremely good magnetic sensors in the nose.
[edit] See also
[edit] References
- Gruber & Sundström (2000). Negaprion brevirostris. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is near threatened
- Negaprion brevirostris (TSN 160433). Integrated Taxonomic Information System. Retrieved on 23 January 2006.
- "Negaprion brevirostris". FishBase. Ed. Ranier Froese and Daniel Pauly. March 2005 version. N.p.: FishBase, 2005.
- Washington Post, 2005, Aug. 22nd: "Scientists Fear Oceans on the Cusp Of a Wave of Marine Extinctions"
[edit] External links
