- Green turtle
"Chelonia" redirects here. It is also the name of the
superorderuniting turtles, tortoises and terrapins ( Testudines) with the "proto-turtle" " Australochelys.Taxobox
name = Green Turtle| status = EN
status_system = iucn2.3
image_caption = Chelonia mydas on a
Hawaiian coral reef.
trend = down
image_width = 240px
phylum = Chordata
classis = Reptilia
ordo = Testudines
familia = Cheloniidae
genus = " Chelonia"
genus_authority = Latreille in Sonnini & Latreille, 1802
species = "Chelonia mydas"
binomial = "Chelonia mydas"
binomial_authority = (Linnaeus, 1758)
"Chelonia mydas", commonly known as the Green turtle , Myda turtle or Green sea turtle is a large
sea turtlebelonging to the family Cheloniidae. It is the only species in the genus"Chelonia".ITIS|ID=173833|taxon=Chelonia mydas|year=2007|date=21 February] The rangeof the species extends throughout tropicaland subtropicalseas around the world, with two distinct populations in the Atlantic and Pacific Oceans. Their common name derives from the green fat underneath their shell.
As a species recognized as endangered by the
IUCNand CITES, "Chelonia mydas" is protected from exploitation in most countries worldwide. It is illegal to collect, harm or kill individual turtles. In addition, many countries have implemented various laws and ordinances to protect individual turtles and turtle nesting areas within their jurisdiction. However, the turtles' populations are still in danger because of several human practices. In some countries, the turtles are still hunted for their flesh and their eggs are collected from nests and eaten as a delicacy. Pollutionindirectly harms the turtle populations both on the population and the individual scale. Many turtles die as a result of being caught in fishermen's nets and drowning. Finally, habitat lossdue to human developmentis a major reason for the loss of green turtle nesting beaches.
Anatomy and morphology
The appearance of the green turtle is that of a typical sea turtle. "Chelonia mydas" has a dorsoventrally-flattened body, a beaked head at the end of a short neck, and paddle-like arms well-adapted for swimmingcite web | title =Green Sea Turtle ("Chelonia mydas") | work =North Florida Field Office | publisher =United States Fish and Wildlife Service | date =
2005-12-29| url=http://www.fws.gov/northflorida/SeaTurtles/Turtle%20Factsheets/Green-Sea-Turtle.htm | accessdate = 2007-02-21] . Adult green turtles are known to grow to convert|5|ft|m longcite book |last=Kindersley |first= Dorling |year=2001,2005 |title=Animal |location=New York City |publisher=DK Publishing |isbn=0-7894-7764-5] . While individuals have been caught that reached weights of up to 315 kilograms (695 lb), the average weight of mature individuals is around kg to lb|200|precision=-1. The largest "Chelonia mydas" ever recorded weighed 395 kilograms (871 pounds).cite web | title =Species Fact Sheet: Green Sea Turtle | work =Caribbean Conservation Corporation & Sea Turtle Survival League | publisher =Caribbean Conservation Corporation | date = 2005-12-29| url=http://www.cccturtle.org/green.htm|accessdate=2007-02-22]
Anatomically, there are a few characteristics that distinguish the green turtle from the other members of its family. Unlike the closely-related
hawksbill turtle, the green turtle's snout is very short and its beakis unhooked. The horny sheath of the turtle's upper jaw possesses a slightly-denticulated edge while its lower jaw has stronger, serrated, more defined denticulation. The dorsal surface of the turtle's head has a single pair of prefrontal scales. Its carapace is composed of five central scutes flanked by four pairs of lateral scutes. Underneath, the green turtle has four pairs of infra-marginal scutes covering the area between the turtle's plastronand its shell. Mature "C. mydas" front appendages have only a single claw (as opposed to the hawksbill's two), although a second claw is sometimes prominent in young specimens.cite web | title =Green Sea Turtle | publisher =MarineBio.org | date = 2007-05-21| url =http://marinebio.org/species.asp?id=51 | accessdate = 2007-09-02 ]
carapaceof the turtle is known to have various color patterns that change over time. Hatchlings of "C. mydas", like those of other marine turtles, have mostly black carapaces and light-colored plastrons. Carapaces of juveniles are dark brown to olive, while those of mature adults are either entirely brown, spotted or marbled with variegated rays. Underneath, the turtle's plastron is hued yellow. "C. mydas" limbs are dark-colored and lined with yellow, and are usually marked with a large dark brown spot in the center of each appendage.cite web | title =Green Sea Turtle ("Chelonia mydas") | work =National Geographic - Animals | publisher =National Geographic Society | date = 2005-12-29| url=http://www3.nationalgeographic.com/animals/reptiles/green-turtle.html|accessdate=2007-02-21] cite book | last =Boulenger | first =G. A. | authorlink = | title =The Fauna of British India, including Ceylon and Burma. Reptilia and Batrachia. | publisher =Taylor & Francis | year =1890 | location =London | pages =541 pp. | url = | doi = | id = ]
url =http://marinebio.org/species.asp?id=51 | accessdate = 2008-10-09 ]
The range of "Chelonia mydas" extends throughout
tropicaland subtropicaloceans worldwide. There are two major subpopulations of "C. mydas", the Atlantic and the Eastern Pacific subpopulations. Each population is genetically-distinct, with has its own set of nesting and feeding grounds within the population's known range.
"Chelonia mydas" can generally be found throughout the entire
Atlantic Ocean. Individuals have been spotted as far north as Canadain the Western Atlantic and the British Islesin the east. The subpopulation's southern range is known until past the southern tip of Africain the east and Argentinain the Western Atlantic. The major nesting sites in the region can be found on various islands in the Caribbean, along the eastern shores of the continental United States, the eastern coast of the South American continent and most notably, on isolated islands in the north Atlantic. and asan d
In the Caribbean, major nesting sites have been identified on
Aves Island, the U.S. Virgin Islands, Puerto Ricoand Costa Rica. One of the most important nesting grounds for the region's green turtle population can be located in Tortuguero in Costa Rica.cite journal | last =Bjorndal | first =Karen A. | authorlink =Karen Bjorndal | coauthors =Jerry A. Wetherall, Alan B. Bolten and Jeanne A. Mortimer | title =Twenty-Six Years of Green Turtle Nesting at Tortuguero, Costa Rica: An Encouraging Trend | journal =Conservation Biology | volume =13 | issue =1 | pages =126–134 | month =February | year =1999 | url = | accessdate = | doi =10.1046/j.1523-1739.1999.97329.x ] In fact, a great majority of the Caribbean region's "C. mydas" population hails from a few beaches in Tortuguero.cite journal | last =Lahanas| first =P. N. | coauthors= K. A. Bjorndal, A. B. Bolten, S. E. Encalada, M. M. Miyamoto, R. A. Valverde and B. W. Bowen| authorlink = | title =Genetic composition of a green turtle ("Chelonia mydas") feeding ground population: evidence for multiple origins | journal =Marine Biology | volume = 130| issue = | pages =345–352 | publisher =Springer-Verlag | year =1998 | url =http://accstr.ufl.edu/publications/Lahanas_et_al_1998_MarBiol.pdf | doi = | id = | accessdate = 2007-09-01|format=PDF] Within United States waters, minor nesting sites have been noted in the states of Georgia, North and South Carolinaand all along the east coast of Florida. Hutchinson Island in particular is a major nesting area in Florida waters. Notable nesting locations in South America include secluded beaches in Surinamand French Guiana.cite journal | last =Girondot | first =Marc | authorlink =Marc Girondot | coauthors =Jacques Fretey | title =Leatherback Turtles, Dermochelys coriacea, Nesting in French Guiana, 1978-1995 | journal =Chelonian Conservation Biology | volume =2 | pages =204–208 | year =1996 | url =http://www.ese.u-psud.fr/epc/conservation/Publi/texte/AE_CCB96.html | accessdate =2007-09-14] In the Southern Atlantic Ocean, the most notable nesting grounds for "Chelonia mydas" are found on the island of Ascension. On that particular island, annual nesting occurs in the volume of around 6,000 to 13,000 individual turtle nests.cite book | last =Seminoff | first =Jeffrey A. | authorlink =Marine Turtle Specialist Group | coauthors =et al. | title =IUCN 2002 Red List Global Status Assessment: Green Turtle ("Chelonia mydas") | publisher = of the World Conservation Union (IUCN) | year =2002
location = | pages =93 | url =http://www.seaturtle.org/PDF/Seminoff_2002_IUCNList.pdf | doi = |format=PDF] cite journal | last =Godley | first =Brendan J. | authorlink = | coauthors =Annette C. Broderick and Graeme C. Hays | title =Nesting of green turtles ("Chelonia mydas") at Ascension Island, South Atlantic | journal =Biological Conservation | volume =97 | issue=2 | pages =151–158 | month =February | year =2001 | url = | doi =10.1016/S0006-3207(00)00107-5 | accessdate = ] cite conference | last =Broderick | first =Annette C. | authorlink = | coauthors =Brendan J. Godley and Graeme C. Hays | title =Monitoring and conservation of marine turtles of Ascension Island: a sustainable resource | booktitle =Interim Report to Foreign and Commonwealth Office Environment Fund for the Overseas Territories | pages =13 pp. | year =2001 | url = | doi = | accessdate = ]
In contrast with the sporadic distribution of their nesting sites, "Chelonia mydas" feeding grounds are much more widely distributed throughout the region. Important feeding grounds for the green sea turtle in
Floridainclude Indian River Lagoon, the Florida Keys, Florida Bay, Homosassa, Crystal Riverand Cedar Key.cite book | last =Audubon | first =Maria R. | authorlink =Maria Audubon | title =Audubon and His Journals: Dover Publications Reprint | publisher =Scribner's Sons | date =1897/1986 | location =New York | pages = 373-375| url = | isbn = 978-0486251448]
In the Pacific, the range of the green turtle reaches as far north as the southern coast of
Alaskaand as far south as Chilein the east. The turtle's distribution in the Western Pacific is known as far north as Japanand even southern parts of Russia's Pacific coast and as far south as the northern tip of New Zealandand a few islands further south of Tasmania. The turtles can be found throughout the entire range of the Indian Ocean.cite map| publisher =Caribbean Conservation Corporation| title =Green turtle nesting sites| url =http://www.cccturtle.org/sea-turtle-information.php?page=green| year =1961| cartography =Center for Marine Conservation| accessdate =2007-08-31]
Significant nesting grounds are scattered throughout the entire region. Pacific green turtle nesting grounds are found in
Mexico, the Hawaiian Islands, the South Pacific, the northern coast of Australiaand Southeast Asia. In the Indian Ocean, major nesting colonies have been recorded in India, Pakistanand other coastal countries in the region. A few nesting grounds have been reported along the east coast of the African continent including some islands in the waters around Madagascar.
East Pacific green turtles nesting grounds are well-studied all along the Mexican coast. These turtles have been found to feed in seagrass pastures in the
Gulf of California.cite journal | last =Seminoff| first =Jeffrey A. | coauthors= Javier Alvarado, Carlos Delgado, Jose Luis Lopez, Gabriel Hoeffer| authorlink = Jeffrey Seminoff| title =First Direct Evidence of Migration by an East Pacific Green Seaturtle from Michoacan, Mexico to a Feeding Ground on the Sonoran Coast of the Gulf of California | journal =The Southwestern Naturalist | volume = 47| issue = 2| pages =314–316 pp. | publisher =Southwestern Association of Naturalists | month =June | year =2002| url = | doi =10.2307/3672922| id = | accessdate = ] Green turtles belonging to the distinct Hawaiian subpopulation are known to nest at the protected French Frigate Shoalssome 800 kilometers to the west of the Hawaiian Islands.cite journal | last =Glick | first =Daniel | authorlink =Daniel Glick | title =Back from the Brink | journal =The Smithsonian Magazine | volume = | issue = | pages =54–55 | publisher =Smithsonian Institution | month =September | year =2005 | url=http://www.smithsonianmag.com/issues/2005/september/brink.php?page=1 | doi = | id = | accessdate = 2007-08-31] In the Philippines, green turtles are known to nest in the Turtle Islands along with closely-related hawksbill turtles.cite web | title =Ocean Ambassadors - Philippine Turtle Islands | work =Coastal Resource & Fisheries Management of the Philippines | publisher =OneOcean.org | date = | url =http://www.oneocean.org/ambassadors/track_a_turtle/tihpa/pti.html | accessdate = 2007-02-06 ] There are also a few nesting beaches in Indonesia, one of them in the Meru Betiri National Reserve in East Java.cite book | authorlink = | title =Indonesian Sea Turtle Conservation | publisher =World Wide Fund for Nature, Indonesia | date = | location =Yayasan, Indonesia | pages =4 pp. | url =http://assets.panda.org/downloads/brochureturtlecop7indonesiacbd.pdf |accessdate=2007-09-16|format=PDF] The green sea turtles on the Great Barrier Reefhave two genetically distinct populations; one in the Northern Great Barrier Reef, and the other in the Southern half of the reef. Within the reef, twenty separate locations consisting of small islands and cayswere identified as nesting sites for either population of "C. mydas". Of these, the most important green turtle nesting ground was identified to be on Raine Island.cite book |last= Dobbs |first= Kirstin |title=Marine turtle and dugong habitats in the Great Barrier Reef Marine Park used to implement biophysical operational principles for the Representative Areas Program |publisher= Great Barrier Marine Park Authority |year=2007 |url=http://www.gbrmpa.gov.au/__data/assets/pdf_file/0007/18799/rap_turtle_and_dugong_bop.pdf| isbn=978-1-876945-58-9 |format=PDF] cite journal | last =Tucker| first =Anton D. | coauthors= Mark A. Read| authorlink = Anton Tucker| title =Frequency of Foraging by Gravid Green Turtles (Chelonia mydas) at Raine Island, Great Barrier Reef | journal =Journal of Herpetology | volume = 35| issue = 3| pages =500–503 pp. | publisher =Society for the Study of Amphibians and Reptiles | month =September | year =2001| url = | doi =10.2307/1565970 | accessdate = ]
Major nesting sites of green turtle are common on either side of the
Arabian Sea, both in Ash Sharqiyah, Oman, and along the coast of Karachi, Pakistan. Some specific beaches along the area, such as Hawke's Bay and Sandspit, are the common nesting grounds for the region's "C. mydas" and "L. olivacea" subpopulation. Sandy beaches along Sindhand Balochistan are also known green turtle nest sites. Some 25 kilometers off the Pakistani coast, Astola island is another known nesting beach.cite web | title = Green Sea Turtle - "Chelonia mydas japonica" | work =Turtles of Pakistan | publisher =Wildlife of Pakistan | year =2003 | url=http://www.wildlifeofpakistan.com/ReptilesofPakistan/greenseaturtle.htm | format = | doi = | accessdate = 2007-02-21 ] cite journal | last =Butler | first =E. | authorlink = | coauthors =A. Astola
title =A summer cruise in the Gulf of Oman | journal =Stray Feathers | volume =5 | issue = | pages =283–304 | year =1877 | url = | doi = | id = | accessdate = ] cite journal | last =Groombridge | first =Brian | authorlink =Brian Groombridge | coauthors =Aban Marker Kabraji and Abdul Latif Rao | title =Marine Turtles in Baluchistan (Pakistan) | journal =Marine Turtle Newsletter | volume =42 | issue = | pages =1–3 | year =1988 | url =http://www.seaturtle.org/mtn/archives/mtn42/mtn42p1.shtml | accessdate = 2007-08-30 ]
December 30, 2007, fishermen, using a "hulbot-hulbot" or a fishnetaccidentally caught an 80-kilogram, 93 centimeters in length and 82 cm wide, green sea turtle off Barangay Bolong, Zamboanga City, Philippines. December is breeding season of the green sea turtles near the Bolong beach. [ [http://www.abs-cbnnews.com/storypage.aspx?StoryId=103926 Abs-Cbn Interactive, Green sea turtle caught in Zamboanga] ]
Ecology and life history
As one of the oldest sea turtle species studied, much of what is known of sea turtle ecology was gleaned from studies of green turtles. The ecology of "Chelonia mydas" changes drastically with each succeeding stage of its life history. For instance, newly-emerged hatchlings are
carnivorous, pelagicorganisms part of the open ocean mini- nekton. In contrast, immature juveniles and adult turtles are commonly found in seagrass meadows closer inshore as herbivorousgrazers.
Green turtles alternate between three
habitattype depending on their current life historystage. Nesting beaches are where the turtles return to lay eggs. Mature turtles spend most of their time in coastal, shallow waters with lush seagrass beds. Seagrass meadows within inshore bays, lagoons and shoals are common locations where adult "Chelonia mydas" can often be found. This particular species is known to be very selective about their feeding and mating sites and entire generations will often alternately migrate between the same feeding and nesting areas.
After hatching, turtles in their first five years are known to spend a majority of their early life stages in convergence zones within the open ocean.cite web | title =Green Turtle ("Chelonia mydas") | work =Fisheries: Office of Protected Resources | publisher =U. S. National Oceanographic Atmospheric Administration | year =2007 | url =http://www.nmfs.noaa.gov/pr/species/turtles/green.htm | accessdate = 2007-09-02 ] These young turtles are rarely seen as they swim in frequent deep,
pelagicwaters where they spend the first few years of their lives.cite journal | last =Reich | first =Kimberly J. | authorlink =Kimberly Reich | coauthors =Karen A. Bjorndal & Alan B. Bolten | title =The ‘lost years’ of green turtles: using stable isotopes to study cryptic lifestages | journal =Biology Letters | volume =6 | issue =in press | pages = 712| date =2007-09-18 | url =http://www.journals.royalsoc.ac.uk/content/k1l8072271716750/ | doi =10.1098/rsbl.2007.0394 | accessdate =2007-09-20] cite news | last =Brynner | first =Jeanna | title =Sea Turtles' Mystery Hideout Revealed | work =LiveScience | language =English | publisher =Imaginova Corp. | date = 2007-09-19| url =http://www.livescience.com/animals/070919_sea_turtle.html | accessdate =2007-09-20]
As large and well-protected animals, adult green turtles have few enemies and even fewer predators. Only human beings and the larger
sharks are known to feed on "C. mydas" adults. Specifically, tiger sharks (" Galeocerdo cuvier") are known predators of adult green turtles in Hawaiian waters. Juvenile turtles and recently-emerged hatchlings have significantly more predators, including crabs, small mammals and shorebirds.
Adult "Chelonia mydas" are obligately
herbivorous. They almost-exclusively feed on various species of seagrasses and seaweed. They have been observed grazing on various species of macroalgae, specifically " Caulerpa", " Turbinaria", " Spyridia", " Codium", and "Ulva".cite web | title =Hawaiian Green Sea Turtle | work = | publisher =Midway Atoll National Wildlife Refuge | date = 2002-09-05| url =http://www.fws.gov/midway/wildlife/turtle.html | accessdate = 2007-09-02 ] While mature green turtles are entirely herbivorous, juveniles are known to subsist on a plethora of marine invertebrates. Select preferred prey items include smaller cnidariansand crustaceans. Their digestive intake of plant matter grows larger as they age, until as mature adults they become obligateherbivores. While it has been previously stated that green turtles do not feed while at their respective nesting areas, it has been shown that gravidturtles do in fact feed while in the waters surrounding their nesting grounds.
Green turtles migrate long distances between their chosen feeding sites and the beaches from where they hatched. Some "C. mydas" are known to swim distances of greater than 2,600 kilometers (1,400 nmi) to reach their spawning grounds. Mature turtles will often return to the same exact beach from which they hatched. Individual female green turtles usually mate every two to four years. Males on the other hand, are known to make the trip to their breeding areas every year.cite press release | title =Australian Threatened Species: Green turtle ("Chelonia mydas") | publisher =Government of Australia | year =2006 | url =http://www.environment.gov.au/biodiversity/threatened/publications/pubs/tsd06green-turtle.pdf | accessdate = 2007-08-15 |format=PDF] As with many species that are found across a wide range of
latitudes, mating seasons vary between populations. For most "Chelonia mydas" in the Caribbean, mating season is from June to September. The French Guiananesting subpopulation nests from March to June. In the tropics, green turtles are known to nest throughout the year, with some subpopulations preferring particular times of the year. In Pakistan, Indian Ocean"C. mydas" nest all year-round but prefer to nest during the months of July to December.
Green turtles reproduce in the typical way that marine turtles do so. Female turtles control mating; males cannot force females to mate. While it does not seem to offer increased survival among the hatchlings, a few green turtle populations are known to undergo
polyandrywhen mating.cite journal | last =Lee | first =Patricia L. M. | authorlink =Patricia Lee | coauthors =Graeme C. Hays | title =Polyandry in a marine turtle: Females make the best of a bad job | journal =Proceedings of the National Academy of Science | volume =101 | issue =17 | pages =6530–6535 | date = 2004-04-27| url =http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=404079#ref45
doi =10.1073/pnas.0307982101 | accessdate =2007-09-07 | pmid =15096623] After mating in the water, the females haul themselves onto the beach above the high tide line. Upon reaching a suitable nesting site, the gravid female then digs a hole with her hind flippers and deposits a number of eggs in the nest. The number of eggs laid per litter depends on the age of the female and differs from species to species, but "C. mydas" clutches range between 100 to 200 eggs. After laying eggs, the female then covers the nest with sand and returns to the sea.
After around 45 to 75 days, the eggs hatch. As with other marine turtles, "C. mydas" eggs hatch during the night and the newly-emerged turtles
instinctively head directly towards the water's edge. This undoubtedly is the most dangerous time in a turtle's life, as the hatchlings make their way to the water, various predators such as gulls and crabs pick off many turtles. A significant percentage of turtle hatchlings never make it to the ocean. Just like other sea turtles, little is known of the early life history of newly-hatched green turtles. After this trek to the ocean juvenile green turtles spend from three to five years in the opean ocean as carnivores before they settle as immature juveniles into a more herbivorous, shallow-water lifestyle. It is speculated that they take twenty to fifty years to reach mature size. Individuals of the species are known to live up to eighty years in the wild.
One of the most significant mass-nesting sites for this species is located on
Ascension Islandin the South Atlantic. Each year on the island, thousands of "C. mydas" create between 6,000 and 15,000 nests. These particular turtles are among the largest green turtles in the world, many more than a meter in length and weighing up to 300 kilograms.>cite web | last =Fowler | first =Stephen | authorlink =Stephen Fowler | title =About The Green Turtle on Ascension | work =Turtles | publisher =Ascension Island Heritage Society | date = 2002-04-21| url =http://www.heritage.org.ac/HS2right.htm | accessdate =2007-09-16]
The green turtle is a member of the tribe
Chelonini. In a study conducted in 1993, the status of the genus"Chelonia" with respect to the other marine turtles was clarified. The carnivorous" Eretmochelys" (hawksbill), " Caretta" (loggerhead) and " Lepidochelys" (Ridley) were confirmed in the tribe Carettini. Herbivorous"Chelonia" were found distinct enough to warrant their status while establishing that " Natator" (flatback) was further-removed than previously believed.cite journal | last =Bowen | first =Brian W. | authorlink =Brian Bowen | coauthors =William S. Nelson and John C. Avise | title =A Molecular Phylogeny for Marine Turtles: Trait Mapping, Rate Assessment, and Conservation Relevance | journal =Proceedings of the National Academy of Sciences of the United States of America | volume =90 | issue =12 | pages =5574 – 5577 | publisher =National Academy of Sciences | date = 1993-06-15| url = | doi = | id = | accessdate = ]
Etymology and taxonomic history
The species was originally described by
Linnaeusin 1758 as "Testudo mydas".ITIS|ID=208662|taxon=Testudo mydas|year=2007|date=23 February] In 1868, Bocourtdescribed a particular species of sea turtle as "Chelonia agassizii" ("Chelonia agassizi" is a commonly-cited misspelling of this taxon).ITIS|ID=655934 |taxon=Chelonia agassizi|year=2007|date=23 February] This "species" was referred to as the "black sea turtle".ITIS|ID=202103 |taxon=Chelonia agassizii|year=2007|date=23 February] However, research determined that the "black sea turtle" was not genetically distinct from "C. mydas" and thus taxonomically not a separate species.cite journal | last =Karl | first =Stephen H. | coauthors = Brian W. Bowen| title =Evolutionary Significant Units versus Geopolitical Taxonomy: Molecular Systematics of an Endangered Sea Turtle (genus "Chelonia") | journal =Conservation Biology | volume =13 | issue =5 | pages =990–999 | publisher =Blackwell Synergy | year =1999 | url=http://www.blackwell-synergy.com/doi/abs/10.1046/j.1523-1739.1999.97352.x | doi =10.1046/j.1523-1739.1999.97352.x | id = | accessdate = 2007-09-09| format =abstract ] These two separate species were then united in the same species, "Chelonia mydas" and were given subspecies status. "C. mydas mydas" referred to the originally described population while "C. mydas agassizi" referred to the Pacific population.ITIS|ID=208663 |taxon=Chelonia mydas agassizi|year=2007|date=23 February] ITIS|ID=173834 |taxon=Chelonia mydas mydas|year=2007|date=23 February] This subdivision was later determined to be invalid and all members of the species were then designated "Chelonia mydas". The oft-mentioned name "C. agassizi" remains an invalid junior synonymof "C. mydas".
common nameis derived not from any particular greenexternal coloration of the turtle. The green turtle is so-called because of the greenish color of the turtle's fat, which is only found in a layer between their inner organs and their shell.cite web | title =green turtle | work =Marine Turtles | publisher =Marine Conservation Society | year =2007 | url =http://www.mcsuk.org/marineworld/turtles/green+turtle | accessdate = 2007-08-30 ] As a species found worldwide, the green turtle is called differently in some languagesand dialects. In Hawaii, the native Hawaiian word "honu" is used to refer to this species.
Importance to Humans
While in most countries, it is now illegal to hunt "Chelonia mydas" along with the other members of its family, sea turtles continue to be caught worldwide. Along with other sea turtles, "Chelonia mydas" are caught both intentionally and unintentionally in select regions of the world. Prior to the implementation of various protection measures, the turtles' skin was tanned and used as
leatherfor handbags, especially in Hawaii. In ancient China, the flesh of sea turtles including and especially "C. mydas" was considered a culinary delicacy.cite journal | last =Schafer | first =Edward H. | authorlink =Edward Schafer | title =Eating Turtles in Ancient China | journal =Journal of the American Oriental Society | volume =82 | issue =1 | pages =73–74 | publisher =American Oriental Society | year =1962 | url= | doi = | id = | accessdate = ] Particularly for this species, the turtle's calipee, fat and cartilageare sought as ingredients for making turtle soup.
Indonesia, sea turtle eggs are a popular delicacy in Java. However, the turtle's flesh is regarded as " ḥarām" or "unclean" under Islamic law(Islam is the primary religion in the region). In Bali, the demand for turtle meat to satisfy traditional consumption at ceremonial and religious feasts has encouraged the harvesting of turtles in the furthest and remotest parts of the Indonesian archipelago.cite book |last=Whitten |first=T |coauthors=Soeriaatmadja, R. E., Suraya A. A. |title=The Ecology of Java and Bali |publisher=Periplus Editions Ltd |year=1996 |location=Hong Kong |pages=pages 756-760 |id=] Bali has been importing sea turtles since the 1950s as its own turtle supplies were said to be severely depleted.Sumertha, I.N. 1974. Perikanan penyu dan cara pengelolaan di Indonesia. "Dokumen. Kom. IPB" 8: 1-18. Cited in cite book |last=Whitten |first=T |coauthors=Soeriaatmadja, R. E., Suraya A. A. |title=The Ecology of Java and Bali |publisher=Periplus Editions Ltd |year=1996 |location=Hong Kong |pages=page 757 |id=] The ethnic Balinese do not eat the eggs, which are instead sold to local Muslims. The former traditional uses of turtle on Bali were once deemed sustainable, but have been questioned considering a vastly larger human population and thus greater demand. The harvest was until recently described to be the most intensive in the world.
Before the inclusion of the turtles in the
Endangered Species Actand the Convention on International Trade in Endangered Species, commercial farms such as the Cayman Turtle Farm in the West Indiesbred the turtles for commercial sale. The farms held as many as 100,000 turtles at any one time. When the markets were closed due to protection measures, some farms went bankrupt and most drastically reduced their stock. The farms have since been converted into tourist attractions with around 11,000 turtles at any one time.cite web | last =Morriss | first =Andrew | authorlink =Andrew Morriss | title =Survival of the Sea Turtle: Cayman Turtle Farm Starts Over | work =PERC Reports | publisher =Property and Environment Research Center | date = | url =http://www.perc.org/about.php?id=825 | accessdate =2007-09-16]
There are various threats to the species' survival. Direct and directed threats to individual turtles include hunting of turtles for their flesh and shells and the harvesting of List of Threatened Animals, according to the 1990cite book| author = IUCN | authorlink =IUCN | title =1990 IUCN Red List of Threatened Animals | publisher =IUCN | year =1990 | location =Gland, Switzerland and Cambridge, UK.] and 1994 editions of the
IUCN Red List.
As a member of the family "
Cheloniidae", "Chelonia mydas" is listed on Appendix I of the Convention on International Trade in Endangered Speciesas of May 3, 2007.cite web| author=CITES | authorlink =CITES | title =Appendices | work = | publisher =Convention on International Trade in Endangered Species of Wild Flora and Fauna | date = 2007-05-03| url =http://www.cites.org/eng/app/appendices.shtml | format =SHTML | accessdate = 2007-08-31 ] The species was originally listed on Appendix II in 1975. The entire family was put onto Appendix I in 1977, with the exception of the Australian population of "C. mydas". In 1981, all populations of the species were brought into Appendix I, including the Australian population. As covered by Appendix I of CITES, it is illegal to import or export, kill, capture or harass green turtles.cite web| author=UNEP-WCMC| authorlink =UNEP-WCMC | title =Chelonia mydas | work =UNEP-WCMC Species Database: CITES-Listed Species | publisher =United Nations Environment Programme - World Conservation Monitoring Centre | date = | url =http://sea.unep-wcmc.org/isdb/CITES/Taxonomy/tax-species-result.cfm?displaylanguage=eng&Genus=Chelonia&Species=mydas&source=animals&Country=&tabname=all
id=A-301.003.002.002| accessdate = 2007-08-31 ]
Country-specific conservation initiatives
In addition to management by global entities such as the
IUCNand CITES, specific countries around the world whose jurisdiction turtle nesting and feeding grounds fall under have taken specific conservation efforts in order to protect the species. Eco-tourismhas been one specific thrust in Sabah, Borneo. The island of Pulau Selinganis home to a turtle hatchery. Staff on the island collect some of the eggs laid each night and place them in a hatchery to protect them from predators. Incubation of the eggs apparently takes around sixty days. Once hatched, touristsare permitted to assist in the release of the baby turtles into the sea.cite web | title =Selingan Turtle Island | work =Borneo: Journey Malaysia | publisher =Dolphin Diaries Travel Sdn Bhd. | year =2007 | url =http://www.journeymalaysia.com/MI_selinganturtleisland.htm | accessdate =2007-09-16] In the United States, the U.S. Fish and Wildlife Services classified "Chelonia mydas" as a threatened species, rendering it a federal offense to capture or otherwise kill an individual turtle. In part due to this, the Hawaiian green turtle subpopulation has made a remarkable comeback and is now also the subject of eco-tourism and has become something of a state mascot. Students of Hawaii Preparatory Academyon the Big Island have tagged thousands of specimens since the early 1990s. In the United Kingdomthe species is protected by a Biodiversity Action Plan, due to harvesting in excess from human overpopulationand marine pollution.cite web | last = | first = | authorlink = | coauthors = | title =Grouped Species Action Plan: Grouped plan for marine turtles | work =UK Biodiversity Action Plan | publisher =UK Joint Nature Conservation Committee | year =2006 | url =http://www.ukbap.org.uk/ukplans.aspx?ID=335 | accessdate =2007-09-16] The Pakistani-branch of the World Wide Fund for Naturehas been initiating various projects for secure turtle hatching since the 1980s. However, the population has continued to decline due to various factors.
In the Atlantic, conservation initiatives have centered around nesting sites in the Caribbean. The
Tortugueronesting beaches in Costa Ricahave been the subject of egg-collection limits since the 1950s. Two decades after, the Tortuguero National Parkformally established in 1976 ensuring the protection of that region's nesting grounds. On Ascension Islandwhere some of the species' most important nesting beaches are, an active conservation program has been implemented.cite web | title =Ascension Conservation | work =Ascension Conservation, Wildlife | publisher =Ascension Conservation | year =2007 | url =http://www.ascensionconservation.org.ac/wildlife.htm | accessdate =2007-09-16] . [http://www.karumbe.org Karumbé] has been monitoring foraging and developmental areas of juvenile green turtles (Chelonia mydas)in Uruguay from 1999.
Chelonioidea". The sea turtlesuperfamily.
Caretta caretta". The loggerhead 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.
* ARKive - [http://www.arkive.org/species/GES/reptiles/Chelonia_mydas/ images and movies of the green turtle "(Chelonia mydas)"]
* US Fish and Wildlife Service sites:
** [http://www.nmfs.noaa.gov/pr/species/turtles/green.html Floridian and Mexican populations]
* [http://www.iucnredlist.org/search/details.php/4615/all IUCN Red List entry]
* [http://fohn.net/green-turtles-facts-pictures/ Desktop wallpaper & fun green turtle facts]
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