Green sea turtle (Chelonia mydas)
Taxonomy:
View taxonomy in ITISListing Status: Endangered and others listed below
The U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) are joint lead Federal agencies responsible for managing this species; the FWS manages the species on land, while NMFS manages the species in water. The information on this page displays mostly FWS data; for additional information on this species, including NMFS regulatory actions such as critical habitat designation or recovery planning, please visit the National Marine Fisheries website (https://www.fisheries.noaa.gov/species-directory/threatened-endangered).
General Information
The green sea turtle grows to a maximum size of about 4 feet and a weight of 440 pounds. It has a heart-shaped shell, small head, and single-clawed flippers. Color is variable. Hatchlings generally have a black carapace, white plastron, and white margins on the shell and limbs. The adult carapace is smooth, keelless, and light to dark brown with dark mottling; the plastron is whitish to light yellow. Adult heads are light brown with yellow markings. Identifying characteristics include four pairs of costal scutes, none of which borders the nuchal scute, and only one pair of prefrontal scales between the eyes.Population detail
The following populations are being monitored: Green sea turtle
» Range Information
Current Range
Current range maps are only shown within the jurisdictional boundaries of the United States of America. The species may also occur outside this region.
Green sea turtles originating from the Central South Pacific Ocean, bounded by the following coordinates: 9 degrees N., 175 degrees W. in the northwest; 9 degrees N., 125 degrees W. in the northeast; 40 degrees S., 96 degrees W. in the southeast; 40 degrees S., 176 degrees E. in the southwest; and 13 degrees S., 171 degrees E. in the west
Listing status: Endangered
- States/US Territories in which this population is known to or is believed to occur: American Samoa, Guam, Northern Mariana Islands
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
- Countries in which this population is known to occur: Cook Islands, Fiji, French Polynesia, Kiribati, Tokelau, Tonga, Tuvalu, United States
Green sea turtles originating from the Central West Pacific Ocean, bounded by the following coordinates: 41 degrees N., 146 degrees E. in the northwest; 41 degrees N., 169 degrees E. in the northeast; 9 degrees N., 175 degrees W. in the east; 13 degrees S., 171 degrees E. in the southeast; along the northern coast of the island of New Guinea; and 4.5 degrees N., 129 degrees E. in the west
Listing status: Endangered
- States/US Territories in which this population is known to or is believed to occur: Guam, Northern Mariana Islands, Palau
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
- Countries in which this population is known to occur: Federated States of Micronesia, Marshall Islands, Papua New Guinea, Solomon Islands, United States
Green sea turtles originating from the Mediterranean Sea, bounded by 5.5 degrees W. Long. in the west
Listing status: Endangered
- States/US Territories in which this population is known to or is believed to occur:
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the Central North Pacific Ocean, bounded by the following coordinates: 41 degrees N., 169 degrees E. in the northwest; 41 degrees N., 143 degrees W. in the northeast; 9 degrees N., 125 degrees W. in the southeast; and 9 degrees N., 175 degrees W. in the southwest Pacific coast of Mexico
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur: Hawaii, US Minor Outlying Islands
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the Eastern Indian and Western Pacific Oceans, bounded by the following lines and coordinates: 41 degrees N. Lat. in the north, 41 degrees N., 146 degrees E. in the northeast; 4.5 degrees N., 129 degrees E. in the southeast; along the southern coast of the island of New Guinea; along the western coast of Australia (west of 142 degrees E. Long.); 40 degrees S. Lat. in the south; and 84 degrees E. Long. in the east
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur:
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the North Indian Ocean, bounded by: Africa and Asia in the west and north; 84 degrees E. Long. in the east; and the equator in the south
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur:
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the Southwest Indian Ocean, bounded by the following lines: the equator to the north; 84 degrees E. Long. to the east; 40 degrees S. Lat. to the south; and 19 degrees E. Long (and along the eastern coast of Africa) in the west
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur:
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the Southwest Pacific Ocean, bounded by the following lines and coordinates: along the southern coast of the island of New Guinea and the Torres Strait (east of 142 degrees E Long.); 13 degrees S., 171 degrees E. in the northeast; 40 degrees S., 176 degrees E. in the southeast; and 40 degrees S., 142 degrees E. in the southwest
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur:
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the East Pacific Ocean, bounded by the following lines and coordinates: 41 degrees N., 143 degrees W. in the northwest; 41 degrees N. Lat. in the north; along the western coasts of the Americas; 40 degrees S. Lat. in the south; and 40 degrees S., 96 degrees W. in the southwest
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur: California
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the North Atlantic Ocean, bounded by the following lines and coordinates: 48 degrees N. Lat. in the north, along the western coasts of Europe and Africa (west of 5.5 degrees W. Long.); north of 19 degrees N. Lat. in the east; bounded by 19 degrees N., 65.1 degrees W. to 14 degrees N., 65.1 degrees W. then 14 degrees N., 77 degrees W. in the south and west; and along the eastern coasts of the Americas (north of 7.5 degrees N., 77 degrees W.)
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur: Alabama, Florida, Georgia, Maryland, North Carolina, Puerto Rico, South Carolina, Texas, Virginia
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
Green sea turtles originating from the South Atlantic Ocean, bounded by the following lines and coordinates: along the northern and eastern coasts of South America (east of 7.5 degrees N., 77 degrees W.); 14 degrees N., 77 degrees W. to 14 degrees N., 65.1 degrees W. to 19 degrees N., 65.1 degrees W. in the north and west; 19 degrees N. Lat. in the northeast; 40 degrees S., 19 degrees E. in the southeast; and 40 degrees S. Lat. in the south
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur: Virgin Islands
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur:
» Candidate Information
No Candidate information available for this species.
No Candidate Assessments available for this species.
No Candidate Notice of Review Documents currently available for this species.
No Uplisting Documents currently available for this species.
» Federal Register Documents
» Species Status Assessments (SSAs)
No Species Status Assessments (SSA's) are currently available for this species.
» Conservation Plans
» Petitions
» Biological Opinions
To see all FWS Issued Biological Opinions please visit the BO Report.
» Life History
Habitat Requirements
Green turtles are generally found in fairly shallow waters (except when migrating) inside reefs, bays, and inlets. The turtles are attracted to lagoons and shoals with an abundance of marine grass and algae. Open beaches with a sloping platform and minimal disturbance are required for nesting. Green turtles apparently have a strong nesting site fidelity and often make long distance migrations between feeding grounds and nesting beaches. Hatchlings have been observed to seek refuge and food in Sargassum rafts.
Food Habits
Hatchling green turtles eat a variety of plants and animals, but adults feed almost exclusively on seagrasses and marine algae.
Movement / Home Range
The green turtle has a worldwide distribution in tropical and subtropical waters. Major green turtle nesting colonies in the Atlantic occur on Ascension Island, Aves Island, Costa Rica, and Surinam. Within the U.S., green turtles nest in small numbers in the U.S. Virgin Islands, Puerto Rico, Georgia, South Carolina, and North Carolina, and in larger numbers in Florida. The Florida green turtle nesting aggregation is recognized as a regionally significant colony. About 200 to 1,100 females are estimated to nest on beaches in the continental U.S. In the U.S. Pacific, over 90 percent of nesting throughout the Hawaiian archipelago occurs at the French Frigate Shoals, where about 200 to 700 females nest each year. Elsewhere in the U.S. Pacific, nesting takes place at scattered locations in the Commonwealth of the Northern Marianas, Guam, and American Samoa. In the western Pacific, the largest green turtle nesting aggregation in the world occurs on Raine Island, Australia, where thousands of females nest nightly in an average nesting season. In the Indian Ocean, major nesting beaches occur in Oman where 6,000 to 20,000 females are reported to nest annually.
Reproductive Strategy
The nesting season varies with the locality. In the Southeastern U.S., it is roughly June through September. Nesting occurs nocturnally at 2, 3, or 4-year intervals. Only occasionally do females produce clutches in successive years. A female may lay as a many as nine clutches within a nesting season (overall average is about 3.3 nests per season) at about 13-day intervals. Clutch size varies from 75 to 200 eggs, with an average clutch size of 136 eggs reported for Florida. Incubation ranges from about 45 to 75 days, depending on incubation temperatures. Hatchlings generally emerge at night. Age at sexual maturity is believed to be 20 to 50 years.
Other
The term "green" applies not to the external coloration, but to the color of the turtle's subdermal fat.
» Other Resources
NatureServe Explorer Species Reports-- NatureServe Explorer is a source for authoritative conservation information on more than 50,000 plants, animals and ecological communtities of the U.S and Canada. NatureServe Explorer provides in-depth information on rare and endangered species, but includes common plants and animals too. NatureServe Explorer is a product of NatureServe in collaboration with the Natural Heritage Network.
ITIS Reports-- ITIS (the Integrated Taxonomic Information System) is a source for authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.
FWS Digital Media Library -- The U.S. Fish and Wildlife Service's National Digital Library is a searchable collection of selected images, historical artifacts, audio clips, publications, and video." +
