Biological Diversity 2001


This photo courtesy of Turtle Trax


Kingdom: Animalia
Phylum:
Chordata
Class: Reptilia
Order: Testudines
Family: Cheloniidae
Genus: Chelonia
Species: Chelonia mydas


This photo courtesy of Cayman Islands Turtle Farm


Conservation Organizations and Informative Pages

 

Broward County, Florida Sea Turtle Conservation Program

This is a county run organization dedicated to the conservation of sea turtles. They give a hotline number if you observe sea turtle hatchlings or sea turtles in need of help in Broward County, Florida (954) 328-0580

Coastal Research and Education Society of Long Island

This site gives information about this organization's studies of Long Island's sea turtles, and general conservation information.

Office of Protected Resources

This office is responsible for enforcing the U.S. Endangered Species Act.

Turtle Trax

This is an informational page devoted to sea turtles and conservation issues.

The Oceanic Resource Foundation

A non-profit scientic research organization dedicated to protecting the global marine environment and biological diversity.

U.S. Fish and Wildlife Service

A government organization that provides information on endangered species and conservation.


This photo courtesy of Turtle Trax

Fun Stuff

Watch a Green Sea Turtle movie!

Play a Green Sea Turtle game!

Buy a Green Sea Turtle puzzle!

 

 

 

 

 

 

 

 

Green Sea Turtle

Introduction

The Green Sea Turtle, Chelonia mydas, is the largest hard-shelled sea turtle in the world. It ranges in length from 2 to 6 feet with males averaging a little larger than females. They can weigh up to 600 pounds. Adult females weigh on average 300 pounds and males weigh just a little more. Their carapace (top shell) can be olive green, brown, or black, depending on geographic location (Crite 2000). Their plastron (bottom shell) is yellow (U.S. Dept. of Commerce 2001). They are called Green Sea Turtles because of the color of their flesh. Their limbs, which are flattened and flipper-like, are used for swimming. Green Sea Turtle hatchlings weigh less than 1 ounce and are 5 to 10 centimeters in length. They are black on top and white on the bottom.

The Green Sea Turtles are found in warm, tropical oceans throughout the world. They live in warm, shallow water, where they spend all of their lives. The only time they leave the water is when females come on shore to nest. These turtles travel hundreds or even thousands of miles to their own hatching grounds to mate and nest, like their mothers before them (Crite 2000). They mate in the waters just of the nesting beaches (Keuper-Bennett and Bennett 2001). Females deposit their eggs at night in a process that takes 2 hours (Keuper-Bennett and Bennett 2001). The average clutch size is 110-115 eggs, and clutches are produced every 2-4 years. The temperature of the incubating eggs determines the sex of the turtle hatchlings (Keuper-Bennett and Bennett 2001).


This photo courtesy of Broward County, FL Sea Turtle Conservation Program

There is some confusion concerning the diet of the Green Sea Turtle because adults feeding is rarely observed in the wild. It is believed that they feed on sea grasses and algae (Keuper-Bennett and Bennett 2001). They also likely feed on crabs, crustaceans, and other submerged aquatic vegetation (CRESLI 2001).

Little is known about Green Sea Turtle behavior other than mating and hatching because they are more easily observable from the shore. Females sometimes emerge from the water and walk along the beach for long distances without building a nest. This is a response due to a predatory threat, disturbance, or lack of a good nesting site (Biological Resource Division 2001). Other aspects of their behavior are noted above.


This photo courtesy of Cayman Islands Turtle Farm

Conservation Status

Green Sea Turtles are considered a threatened species in the United States. They are endangered in the state of Florida (U.S. Fish and Wildlife Service 2001). The IUCN (World Conservation Union) lists them as endangered (Crite 2001). The CITES (Convention on International Trade in Endangered Species) list classifies them as endangered (CITES 2001).


This photo courtesy of Turtle Trax

Conservation Issues

There are a plethora of conservation issues surrounding the Green Sea Turtle. Coastal areas, the Green Sea Turtle's nesting habitat, are very sensitive and must be managed carefully if the species is to recover. Both the over-development and erosion of beaches that may be caused in part by the planting of non-native plant species reduce the turtles' available nesting habitat (Biological Resource Division 2001)(U.S. Dept. of Commerce 2001). A large amount of artificial lighting near beaches disturbs female turtles and prevents them from laying eggs. It also causes hatchlings to move in the wrong direction (away from the ocean) after they hatch since they are attracted to light sources (ORF 2000). Since the sex of turtle hatchlings is determined by incubation temperature, the sex ratio of hatchlings may be changed when trees are planted to provide shade on beaches. The development of marinas and docks causes a loss of the turtles' feeding habitat. The heavy use of beaches by humans and offroad vehicles compacts the sand, which makes it more difficult for baby turtles to dig their way out of the nest. And the heavy use of Green Sea Turtle habitat by recreational boats causes eventual collisions between boat propellers and turtles (U.S. Dept. of Commerce 2001).

In addition to the various activities and practices that affect Green Sea Turtles' nesting habitat are several more direct activities in which people engage that affect the well-being of the species. People capture turtles for a variety of reasons that include the human consumption of eggs (considered by some to be an aphrodisiac) and meat (used in turtle soup) as well as the sale of turtle leather and shells (Biological Resource Division 2001)(CRESLI 2001). While the illegal capture of Green Sea Turtles is uncommon in the U.S., it is rather common in the Caribbean and is a large problem (ORF 2000). Also, a wide array of current fishing practices result in the accidental capture and possible death of turtles. They may get trapped or tangled in nets or traps and drown.. (Biological Resources Division 2001). Marine pollution also affects Green Sea Turtles chances for survival. Feeding turtles often eat ocean garbage which affects their metabolism and the functioning of thier digestive system. Oil spills will have an effect on their respiratory system, skin, and blood chemistry (U.S. Dept. of Commerce 2001).

Green Sea Turtles, which are currently an endangered species, are protected in the United States under the Endangered Species Act (ESA) of 1973, and under international standards, like those of CITES, which protects green sea turtles in over 150 countries (CITES 2001). The ESA, in cooperation with the U.S. Fish and Wildlife Service (USFWS), prohibits capture, possession, sale, and hunting of the green sea turtle, gives money and land to states to aid conservation efforts, and imposes civil and criminal punishment on violators of these mandates. The Office of Protected Resources is given government responsibility for implementing the ESA for sea turtles (U.S. Department of Commerce 2001).

Despite federal protection of the Green Sea Turtle in the U.S., the Green Sea Turtle continues to be threatened by humans. The public can help to protect them by avoiding nests and nesting areas, keeping bright lights from shining on the beach, keeping litter (especially plastic bags that are often mistaken as jellyfish by turtles) off the beach, and reporting poachers to authorities (Biological Resource Division 2001). There are also local education and protection organizations that often appreciate recieving information about observations of sea turtles. These organizations offer several ways to get involved in Green Sea Turtle conservation, and the help of individuals is welcome and needed.

Literature Cited

Biological Resource Division. Biological Resources Division. 2001. "Sea Turtle Conservation Program." www.co.broward.fl.us/bri00600.htm Accessed October 31, 2001

CITES. Convention on International Trade in Endangered Species of Wild Fauna and Flora. 2001 November 12. "UNEP-WCMC Database-Animals." www.cites.org/eng/resources/fauna.shtml

CRESLI. Coastal Research and Education Society of Long Island, Inc. 2001. "Green Sea Turtle." www.cresli.org Accessed October 31, 2001

Crite, Janel. University of Michigan. 2000 May. "Chelonia Mydas." animaldiversity.ummz.umich.edu Accessed 2001 October 30, 2001

Keuper-Bennett and Bennett. Turtletrax. 2001. "The Atlantic Green Turtle (Chelonia Mydas)." www.turtles.org/atlgrnd.htm Accessed October 31, 2001

ORF. Oceanic Resource Foundation. 2000. "The Green Sea Turtle." www.orf.org/turtles_green.html Accessed October 31, 2001

U.S. Department of Commerce. Office of Protected Resources. 2001 April 13. "Green Sea Turtle (Chelonia Mydas)." www.nmfs.noaa.gov/prot_res/PR3/Turtles/turtles.html Accessed October 31, 2001

U.S. Fish and Wildlife Service. USFWS Species Information. 2001 July 9. "Threatened and Endangered Species System: Chelonia mydas." endangered.fws.gov/wildlife.html Accessed November 14, 2001

 

 

Authors: Karen Hibbard-Rode and Matt Klostermann
Creation/revision date: 11-27-01



Acanthaster planci Apis mellifera Capybara Chimpanzee Danaus plexippus Exciting Cephalopods Green Sea Turtle (H-R,K) Green Sea Turtle (B,M,C) Green Serpent Star Holothuroidea Hyenas Latimeria chalumnae Mudpuppy Northern Leopard Frog Pink Seafan Salamanders Scyphozoa Tuatara

This website is part of a Biology 26 class project on the conservation of global biodiversity.


Earlham · Biology Department · Biology 26: Biological Diversity

Copyright ©-2001 Earlham College. Revised 1 October 2001. Send corrections or comments to klostma@earlham.edu