Atlantic Ridley Sea Turtle Fact Sheet
Atlantic Ridley or Kemp's Ridley Sea Turtle
New York Status: Endangered
Federal Status: Endangered
The smallest member of the sea turtle family, this reptile is also considered the most endangered. Adults grow to a length of 20-28 inches (51-71 cm) and weigh 80-110 pounds (36-50 kg). Atlantic ridley sea turtles have a distinctive round to heart-shaped shell that ranges in color from gray-brown to olive to black. The underside is yellowish on adults and white on juveniles. Prey items include crabs, fish, jellyfish, squid, snails, clams, starfish and some marine vegetation.
Females deposit eggs in aggregations called "arribadas" (meaning arrival) between April and mid-August, on days when the weather is cloudy and relatively cool, with a strong northern wind. Nesting in 1-2 year cycles, sexually mature females lay 1-3 clutches every season. Clutches are laid at intervals of 20-28 days and average 110 eggs each. The young hatch after 50-70 days, emerging just after dawn and scrambling to the water's edge. The tiny turtles drift with the currents or become associated with rafts of sargassum weed. Sexual maturity is reached at the age of 6 years or more. Longevity in the wild is unknown, but in captivity Atlantic ridley sea turtles may live to more than 20 years of age.
Distribution and Habitat
The range extends mainly along the Gulf of Mexico from Florida to the Mexican border, and around the Bay of Campeche. Juveniles inhabit the Atlantic Coast from Florida to the Canadian Maritime Provinces, possibly following the warm Gulf Stream. Juveniles are also found on the shores of Europe and the Mediterranean Sea. Preferred habitats include sheltered areas along the coastline,such as large estuaries, bays and lagoons.
Nesting grounds are restricted to a single stretch of beach near Rancho Nuevo, Tamaulipas, Mexico. The shores of Louisiana may be a primary development area and foraging ground.
Long Island's waters have been identified as critical habitat for immature Kemp's ridleys, providing important habitat for development during the early stages of life (2-5 years).
Previously abundant populations were depleted in the 1940's when Atlantic ridley sea turtles' meat, leather and eggs became valuable. Predation by coyotes and humans on the nesting beach was high, and fishing for both adults and juveniles was a common practice. In 1947, an estimated 40,000 females were recorded on film at the nesting beach. In the 1960's, nesting attempts had fallen to about 5,000. In 1986, only 621 females were recorded nesting. Currently, destruction of coastal beaches due to development, human activity on beaches, drowning in fishing nets and pollution are also threats.
Management and Research Needs
The exploitation of Atlantic ridley sea turtles for their meat and eggs is now illegal and the trade of all products has been banned. The species has been protected in Mexico since 1966, and in the U. S. since 1973 under the Endangered Species Act. The nesting beach in Mexico has been protected by armed guards since 1966. One of seven proposed nature preserves along the Mexican coast, it will presumably be protected from development.
In 1978, the U. S. Fish and Wildlife Service, National Park Service, Texas Parks and Wildlife Department, Florida Audubon Society, and the Mexican government joined forces with a private group in transplanting eggs to Texas beaches in an effort to start a new nesting population. These agencies also called for head-starting young by raising them for a year at the National Marine Fishery Service hatchery, then releasing them into the wild.
A five-year DEC study to evaluate the importance of Long Island sound as critical habitat for Atlantic ridley sea turtles was completed in 1993.
A Stranding Network was established in 1980 through the cooperation of the New York State Department of Environmental Conservation and the National Marine Fisheries Service. Through this system, strandings can be reported to the Riverhead Foundation for Marine Research and Preservation by calling a hotline number: (631) 369-9829.
In response to sea turtle mortality in trawl nets, the U. S. Fish and Wildlife Service has issued regulations requiring shrimp trawlers on the southeastern and Gulf coasts to have a turtle excluder device (TED) on their nets. This device allows turtles and other large marine life to escape should they enter a net. Despite these conservation efforts, it is unclear whether populations of Atlantic ridley sea turtles will recover from past exploitation.
Bjorndal, K. A., Ed. 1981. Biology and Conservation of Sea Turtles. Smithsonian Institution Press, Washington, DC
Carr, A. 1952. Handbook of Turtles. Cornell University Press, Ithaca and London.
Conant, R. and J. T. Collins. 1998. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. Third Edition Expanded. Houghton Mifflin Co., Boston.
Hopkins, S. R. and J. Richardson. 1984. Recovery Plan for Marine Turtles. National Marine Fisheries Service.
National Marine Fisheries Service and U. S. Fish and Wildlife Service. 1995. Status Reviews for Sea Turtles Listed Under the Endangered Species Act of 1973. National Marine Fisheries Service, Silver Spring, Maryland.
Sternberg, J. 1981. Sea Turtles. Center for Environmental Education, Washington, DC
Drawing by Carol Decker