Loggerhead Sea Turtle

Loggerhead Sea Turtle

Taxobox
name = Loggerhead Sea Turtle
status = EN
status_system = iucn3.1



image_width = 250px
regnum = Animalia
phylum = Chordata
classis = Sauropsida
subclassis = Anapsida
ordo = Testudines
familia = Cheloniidae
genus = "Caretta"
genus_authority = Rafinesque, 1814
species = "C. caretta"
binomial = "Caretta caretta"
binomial_authority = Linnaeus, 1758

The Loggerhead Sea Turtle ("Caretta caretta") is a sea turtle and the only member of the genus "Caretta". The genus name "Caretta" is a latinization of the French "caret", meaning turtle, tortoise, or sea turtle [http://www.widecast.org/sea/definitions.cfm] . A loggerhead sea turtle reportedly grows up to 800 lbs (364 kg) and convert|3.5|ft|m long. [] Their shell color is a reddish brown color, and the color of their skin is brown yellow.

Ecology and life history

Trophic ecology

The species feeds on mollusks, crustaceans, fish, jellyfish, the Portuguese Man o' War, and other small- to medium-sized marine animals, which they crush with their large and powerful jaws. As with other sea turtles, females return to lay their eggs on or near the same beach where they hatched. Unlike other sea turtles, courtship and mating usually do not take place near the nesting beach, but rather along the migration routes between feeding and breeding grounds.

Scientists in Hawaii use satellite transponders to track loggerhead sea turtles in the Northern Pacific Ocean.cite web |url= http://www.hanahou.com/pages/Magazine.asp?Action=DrawArticle&ArticleID=704&MagazineID=44 |title= Mapping the Void |author= Dennis Hollier |work= Hana Hou!, Vol. 11, No. 4 |date= August/September 2008 |quote= ]

Life history

In the Mediterranean, Loggerheads mate from late March to early June. The female nesting season is at its peak in June and July, but this depends on the nesting beach. The clutch may vary from 70 to 150 eggs. Each egg is roughly the size and shape of a ping-pong ball. The average interval between nesting seasons is two to three years.

Loggerheads turtles are the most common sea turtle to nest in the United States. Loggerheads nest from Texas to Virginia to North Carolina, requiring soft sandy beaches, where there is little light; with the largest concentration of nests in south Florida. Statistics collected in Florida since 1998 however indicate the lowest nesting levels Florida has seen in 17 years, where nesting rates have declined from 85,988 nests in 1998 to approximately 45,084 in 2007. [ [http://news.yahoo.com/s/ap/20080420/ap_on_sc/sea_turtles_nesting;_ylt=AlFZ3XlaOw00HUIb4FQLmgtvieAA] ]

After approximately 60 days, the hatchlings emerge usually at night when protection from predation is greater. Usually following the brightest light to the ocean's edge, an artificial light, such as from a home can lead them astray. Once in the ocean they use ocean currents to travel to the Sargasso Sea using the Sargassum as protection until they mature. [ [http://news.bbc.co.uk/1/hi/sci/tech/7477519.stm BBC NEWS | Science/Nature | Turtles return home after UK stay ] ]

An alternative to migration for many loggerheads is hibernation to varying degrees as the water cools. Loggerhead turtles have no bones on the tip of their front legs. By February they are submerged for up to seven hours at a time, emerging for only seven minutes to recover. Although outdone by freshwater turtles, these are the longest recorded dives for any air-breathing marine vertebrateHochscheid, S., F. Bentivegna & G.C. Hays. (2005) "First records of dive durations for a hibernating sea turtle." "Biol. Lett." 1(1): 82-6.] .

Most loggerheads that reach adulthood live for longer than 30 years, and can often live past 198.7 years. They are immune to the toxins of a Portuguese Man O' War as the turtles have often been seen feeding on them.

Etymology and taxonomic history

Two subspecies are recognized: "Caretta caretta gigas", is found in the Indian and Pacific Oceans, and "C. caretta caretta", the Atlantic loggerhead, also found in south Italy and the Greek islands of Zakynthos, Kefalonia, Crete and the Peloponese and in Dalyan in southwestern Turkey. (see article; June Haimoff).

Importance to humans

Loggerhead Sea Turtles were once intensively hunted for their meat and eggs, along with their fat which was used in cosmetics and medication. The Loggerhead Sea Turtles were also killed for their shells, which are used to make items such as combs. As a result both subspecies are now internationally protected.

Conservation

Today the main threat to the adult loggerheads lies in shrimp trawls and crab fishing nets, to which many loggerheads annually fall victim. Furthermore, adults are often injured by speedboat propellers and by swallowing fishing hooks or getting caught in nets. Internationally animal protection organizations take pains to monitor and protect the turtles' nesting grounds in Turkey, [cite web
url=http://www.seaturtle.org/mtn/archives/mtn108/mtn108p14.shtml
title=Loggerhead Turtles in the Dalyan River, Mulğa Province, Turkey, 2004
publisher=seaturtle.org
accessdate=2007-06-27
] Greece, Bonaire and Costa Rica. The turtles can also be found around the Italian islands of Lampedusa and Linosa, off the coast of Sicily, and in Calabria, where it is particularly endangered. Furthermore, the turtles are known to nest on the beaches of Cyprus, especially Akamas and Alagadi Beach. [cite web
url=http://www.naturebay.co.uk/north_cyprus_turtles.htm
title=Turtles of North Cyprus, 2007
] In many places during the nesting season workers search the coastline to find evidence of nests. Once found a nest will be uncovered and the eggs carefully counted, if the nest is dangerously located the eggs will be moved to a better spot. Plastic fencing will be placed at or near the surface to protect the eggs from large predators such as raccoons or even dogs. The barrier used is large enough to allow the hatchlings to emerge without difficulty. The nests are checked daily for disturbances, several days after there is indication that the eggs have hatched the nest will be uncovered and the tally of hatched eggs, undeveloped eggs, and dead hatchlings will be recorded. If any hatchlings are found, they are either taken to be raised and released, or taken to research facilities. Ones that appear strong and healthy may instead be released to the ocean. Typically those that lacked the strength to hatch and climb to the surface by that point would have died otherwise.

Hatchlings require the travel from their nest to the ocean in order to build up strength for the journey ahead, so interfering by helping it to the ocean actually lowers their chances of survival.

It is listed as "Endangered" under both Australia's Environment Protection and Biodiversity Conservation Act 1999 and Queensland's Nature Conservation Act 1992.

ee also

*"Chelonioidea". The sea turtle superfamily.
*"Chelonia mydas". The green turtle.
*"Dermochelys coriacea". The leatherback turtle.
*"Eretmochelys imbricata". The hawksbill turtle.
*"Lepidochelys kempii". The Kemp's Ridley turtle.
*"Lepidochelys olivacea". The olive ridley turtle.
*"Natator depressus". The flatback turtle.

References

Bibliography

* Database entry includes a brief justification of why this species is endangered and the criteria used
* [http://dep.state.ct.us/cgnhs/nddb/reptiles.htm Connecticut Department of Environmental Protection - Endangered, Threatened & Special Concern Reptiles]
* [http://news.yahoo.com/s/ap/20070922/ap_on_go_ot/loggerhead_turtles_2]

External links

* International: [http://www.seaturtlestatus.org/Main/Report/SwotReport2.aspx SWOT Report, volume 2] - Featuring the loggerhead nesting beaches of the world along with the most up-to-date information on the global status of loggerhead populations, conservation and natural history.
* International: ARKive - [http://www.arkive.org/species/GES/reptiles/Caretta_caretta/ images and movies of the loggerhead turtle "(Caretta caretta)"]
* U.S.: [http://www.nmfs.noaa.gov/pr/species/turtles/loggerhead.htm Loggerhead Turtle] - by NOAA Fisheries Office of Protected Resources
* U.S.: [http://www.fws.gov/northflorida/SeaTurtles/loggerhead-recovery/default-loggerhead.htm Atlantic Loggerhead Sea Turtle Recovery Plan] - a project of U.S. Fish & Wildlife Service and NOAA
* Florida: [http://northflorida.fws.gov/SeaTurtles/Turtle%20Factsheets/loggerhead-sea-turtle.htm Loggerhead Sea Turtle] - by U.S. Fish & Wildlife Service's North Florida Field Office
* Florida: [http://research.myfwc.com/features/category_main.asp?id=1289 Florida Sea Turtle information] - Florida Fish and Wildlife Conservation Commission [http://research.myfwc.com/ Fish and Wildlife Research Institute]
* Georgia: [http://www.tybeemsc.org/turtles.html Tybee Island, Georgia Sea Turtle Project]
* Hawaii: [http://www8.nos.noaa.gov/onms/park/Parks/SpeciesCard.aspx?refID=6&CreatureID=1096&pID=12 Loggerhead Turtle] - United States National Marine Sanctuary, Northwestern Hawaiian Islands
* Caribbean: [http://cccturtle.org/ Caribbean Conservation Corporation & Sea Turtle Survival League]
* Greece: [http://www.gozakynthos.gr/zakynthos.ecology.caretta.turtle.php Go Zakynthos about Caretta Turtle]
* Greece: [http://www.kateliosgroup.org/ Katelios Turtle Group, Kefalonia]
* Greece: [http://www.archelon.gr Sea Turtle Protection Society of Greece (Archelon)]
* Africa: [http://www.cms.int/species/africa_turtle/AFRICAturtle_bkgd.htm Marine Turtles-Africa] - Convention on Migratory Species
* Brazil: [http://www.tamar.org.br/ingles/ TAMAR Marine Turtle Project]

they need care


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • Sea turtle — Sea turtles An olive ridley sea turtle Scientific classification Kingdom …   Wikipedia

  • Sea turtle — Sea tur tle (Zo[ o]l.) (a) Any one of several very large species of chelonians having the feet converted into paddles, as the green turtle, hawkbill, loggerhead, and leatherback. They inhabit all warm seas. (b) The sea pigeon, or guillemot. [1913 …   The Collaborative International Dictionary of English

  • Green sea turtle — Chelonia redirects here. It is also the name of the superorder uniting turtles, tortoises and terrapins (Testudines) with the proto turtle Australochelys. Green sea turtle Chelonia mydas swimming above a Hawaiian coral reef …   Wikipedia

  • Flatback sea turtle — Conservation status Data Deficient ( …   Wikipedia

  • sea turtle — any of several large turtles of the families Cheloniidae and Dermochelyidae, widely distributed in tropical and subtropical seas, having the limbs modified into paddlelike flippers: all sea turtles are either threatened or endangered through most …   Universalium

  • sea turtle — noun any of various large turtles with limbs modified into flippers; widely distributed in warm seas • Syn: ↑marine turtle • Hypernyms: ↑turtle • Hyponyms: ↑green turtle, ↑Chelonia mydas, ↑loggerhead …   Useful english dictionary

  • Kemp's ridley sea turtle — See also: Olive ridley sea turtle and Ridley sea turtle Kemp s ridley sea turtle Lepidochelys kempii …   Wikipedia

  • Olive ridley sea turtle — An olive ridley in Tamil Nadu, India Conservation status …   Wikipedia

  • Leatherback sea turtle — For the musical instrument called lute, see Lute. Leatherback sea turtle Conservation status …   Wikipedia

  • sea turtle — noun Date: 1612 any of two families (Cheloniidae and Dermochelyidae) of widely distributed marine turtles that have the feet modified into paddles and that include the green turtle, leatherback, hawksbill, loggerhead, and ridley …   New Collegiate Dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”