Kemp's Ridley Sea Turtle
Lepidochelys kempii

* Federal Endangered State Endangered *

Common Name:

Kemp's Ridley Sea Turtle

Scientific Name:

Lepidochelys kempii

Etymology:

Genus:

Lepidochelys is derived from the Greek word lepidos which means "scale" and chelys which means "tortoise". This refers to the oar like flippers.

Species:

kempii was assigned to honor Richard M. Kemp, a 19th century Florida naturalists.

Average Length:

23 - 27.5 in (58 - 70 cm)

Virginia Record Length:

23.1 in. (58.7 cm)

Record length:

29.5 in. (74.9 cm)

PHYSICAL DESCRIPTION: This is the smallest sea turtle with a weight of 35-49 kg and the length 56-79 cm. The largest Ridley recorded in Virginia was 58.7 cm curved carapace length. The adults have a gray carapace that can sometimes be more green or black in color and the plastron is white *10760*. The carapace is heart-shaped, keeled, and smooth and has 5 pairs of pleural shields. Carapace is as wide as long. They have 12-14 marginal scutes on each side with 5 vertebrals. The vertebral scute closest two the head is rhomboidal in shape and it and the first pleural scute on each side contact the cervical scute on leading edge of carapace *10760*. The head is triangular and gray. The limbs are paddle-like and gray with the front flippers having one large claw. The hatchlings are all black with a white edging to the flippers and carapace *1047,1027,1026*. The juveniles have a carapace length of 38-46 mm and weigh 13.5-21.0 grams. Males and females are not sexually dimorphic except the male's tail is visible beyond the edge of the carapace . The beak is parrot-like and the color ranges from light gray to grayish-brown or even an olive green *10760*. Confusing species: This species may be confused with loggerhead turtles (Caretta caretta) but they are reddish-brown in color, and larger. They also resemble green turtles (Chelonia mydas) and hawksbills (Eretmochelys imbricata) but the first anterior vertebral scute is triangular rather than rhomboidal *10760*.

REPRODUCTION: Breeding does not occur in Virginia. With few exceptions, breeding occurs only on a 24 km of beach in Tamaulipas, Mexico. In that area the breeding season is from April-June. There is 1 breeding season per year and the females nest 3 times per season. The inter-nesting period is 10-28 days. There are 110 eggs per clutch, and the females nest during daylight after strong winds. Copulation occurs just offshore from the nesting beach *1047,1028*. A sand beach in which the back berm and fore-dunes are well above high tide levels is necessary for egg laying. The optimum moisture content at the nest site ranges from 10-20 percent saturation. The females consistently used nest sites with a mean of 14 percent moisture from 1983-1985. The minimum breeding age in the wild is seven years. In captivity, the age of maturity is five and one half years. Breeding takes place at the nesting beach at nesting season and they come ashore to lay, in mass, during daylight hours. As many as 200 females may come ashore to lay eggs. The incubation period is from 45-70 days *8816*. Eggs are spherical, 35.0-44.5 mm in diameter (avg. = 38.9) and weight 24-41 grams (avg. = 30.0) *10760*.

BEHAVIOR: This species is an opportunistic feeder on concentrations of portunid crabs and may feed in groups. They exhibit aggressive behavior toward each other in captive rearing. This species is mostly diurnal, both in feeding and nesting. Submerged aquatic vegetation is a primary habitat for juvenile Ridleys in the Chesapeake Bay, Virginia which has the largest concentration of this size class *10760*. It has been inferred that males are more pelagic than females, which are restricted to shallow waters just offshore. The average movement of turtles is between 18-37 km per day but individuals have been known to move as much as 35 km in a day, although this may be influenced by the Gulf Stream current. The young drift in a clockwise direction around the Gulf passing by southern Florida and along the Atlantic coast to New England *8816*. Foraging juveniles, subadults and adults are found chiefly in the area from the Florida keys to High Island, TX in U.S. waters *8816*.

POPULATION PARAMETERS: The sex ratio is assumed to be 1:1. The total mortality was 0.897 in 1977 and 0.847 in 1979 with survival rates of 0.408 and 0.428. Other data indicates a 3-4 percent decline per year. In 1947, 100,000 females nested, in the early 1970's 2-3,0000 and and in 1986, 572 females nested *8816*.

AQUATIC/TERRESTRIAL ASSOCIATIONS: There is a predator prey relationship between the Ridley and brachyuran crabs. In the Chesapeake bay they are almost always found in association with shallow waters with sea grass meadows. Their preferred food source in the bay is blue crabs (Callinectes sapidus) *10760*. Many mature females have medium size barnacles attached to the head, carapace and plastron. They are preyed upon by coyotes, sand crabs, red drum, jackfish, sharks and avian predators *8816*. They rely on only one nesting beach for reproduction and man are their greatest enemy *1047*.

References for Life History

  • 1026 - Bustard, R., 1973, Sea turtles: Natural history and conservation, 22 pgs., Taplinger Publ., New York, NY
  • 1027 - Carr, A.F., 1952, Handbook of Turtles. Turtles of the United States, Canada, and Baja California, 542 pgs., Comstock Publ. Assoc., Cornell Univ. Press, Ithaca, NY
  • 1028 - Carr, A.F., 1967, So excellent a fishe, 248 pgs., The Natural History Press, Garden City, NY
  • 1047 - U.S. Fish and Wildlife Svc., 1980, Selected vertebrate endangered species of the sea coast of the United States: Kemp's (Atlantic) ridley sea turtle, FWS/OBS-80/01.12, U.S. Fish and Wildlife Svc., Washington, DC
  • 8816 - Service, U.S. Fish and Wildlife, 1988, Endangered Species Information System Booklet: Kemp's Ridley Sea Turtle., U.S. Fish and Wildlife Service, Arlington, VA
  • 8818 - Keinath, J.A., J.A. Musick, R.A. Byles, 1987, Aspects of the biology of Virginia's sea turtles: 1979-1986, Virginia J. Science, Vol. 38(4), pg. 329-336
  • 8819 - Bellmund, S, J.A. Musick, R.E. Klinger, R.A. Byles, J.A. Keinath, D.E. Barnard, 1987, Ecology of sea turtles in Virginia, VIMS Special Scientific Report, Vol. 119, 48 pgs., VA Inst. Marine Sci., Coll. Wm and Mary., Gloucester Point, VA
  • 8850 - Service, U.S. Fish and Wildlife, 1985, A recovery plan for marine turtles. , 363 pgs., U.S. Fish and Wildlife Service, Atlanta, GA
  • 10760 - Mitchell, J. C., 1994, The Reptiles of Virginia, 352 pgs., Smithsonian Institution Press, Washington, DC

Photos:

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Verified County/City Occurrence

Accomack County
Gloucester County
Hampton City
Lancaster County
Mathews County
Middlesex County
Newport News City
Northampton County
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Poquoson City
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Verified in 14 Counties/Cities.



FROGS

Virginia is home to 28 species of frogs and toads.

SALAMANDERS

We have a large diversity of salamanders consisting of 56 different species and subspecies.

LIZARDS

Virginia is home to 9 native lizard species and two introduced species, the Mediterranean Gecko and the Italian Wall Lizard.

SNAKES

The Commonwealth is home to 34 species and subspecies of snake. Only 3 species are venomous.

TURTLES

Virginia has 25 species and subspecies of turtle. Five of these species are sea turtle.