FREE ESSAY ON RIDLEY'S SEA TURTLE

RIDLEY'S SEA TURTLE

Sea Turtles
Each species of sea turtle is distinctive in appearance and behavior, all sea turtles
have certain characteristics in common the shell consist of a carapace (upper part) and
plastron (lower part), which are joined together by cartilage called a bridge. in most
species with the exception of the leatherback scutes cover the carapace. Like all turtles
sea turtles have no external ears, they hear best at low frequencies and their sense of
smell is excellent. Though their vision underwater is good, on land they are
nearsighted.
Sea turtles spend most of their time underwater but must come up to breath. During
routine activities sea turtles can dive for about three to five minutes. Sea turtles can
sleep for several hours underwater, but their ability to hold their breath is shortened
by high activity and stress. This is why sea turtles drown in shrimp nets and other gear
in a short time. Adult sea turtles sleep near rocks or under ledges. Hatchlings and
juveniles sleep on the surface with their front flippers pulled back over the carapace. 
Kemp's ridley sea turtle (Lepidochelys kempi)
Charming Tortoise of Kemp
Ridleys are the smallest of the sea turtles. The Kemp's ridley is slightly larger than
the olive ridley, measuring 24 - 28 inches in carapace length and weighing 78 - 100
pounds when mature. An adult is olive green on top and yellowish in color on the bottom,
with a large head and powerful jaws. The carapace is circular to heart shaped. Hatchlings
are dark gray and about an inch and a half long. 
Kemp's ridleys were first discovered and described in 1880 by Samuel Garman. But until
the 1940's was not recognized as a species and was often confused with the olive ridley
and the loggerhead. Confusion continued through the 1950's with many biologist convinced
that the ridleys sea turtle was a sterile hybrid of the green and the loggerhead turtles.
No one could find nesting beaches or an egg-bearing female.
In 1963 an old film was discovered, made in 1947 by Mexican engineer Andres Herrera that
showed nesting ridleys. The film showed an estimated 40,000 Kemp's ridleys nesting on an
isolated beach now called Rancho Nuevo in Tamaulipas, Mexico, 200 miles south of Texas.
Ninety-five percent of the population comes to the 17 mile strip of beach. The other five
percent nest at the adjacent beach in Veracruz. No other sea turtle species goes almost
entirely to one nesting spot to breed. 
The arribada (Spanish for arrival) of Kemp's ridleys in Mexico occurs at irregular
intervals between April and June. Arribadas may occur several times a season. Male and
Females congregate to mate off the coast of the beaches using wind direction velocity ,
lunar cycles and water temperature to gather is a theory. Once mated females wait for
ideal conditions to come ashore. Conditions generally are high wind and heavy surf. The
high wind cools stressed females and hides traces of the nest from predators. Mass
nesting is thought to be a predator swamping where females and hatchlings will die but
many more will survive. 
Herrera's film is now being used as a base line to measure the rapid decline of Kemp's
ridleys since 1947. forty thousand turtles declined to two thousand in 1966. In 1966
Mexican officials set up its first camp to monitor and protect turtles from egg takers.
In 1977, Rancho Nuevo was declared a National Reserve by Mexico. Programs were developed
to help protect turtles from poachers and predators. Now eggs are moved to protective
enclosures to decrease the death to predators. Every year 50,000 hatchlings are released
each year. Even with these programs nest counts in 1993 showed that there were only 400
nesting females. These small numbers result in broken up arribadas into small groups and
solitary nestings. The remaining females lay fewer than 1000 nest each year. 
The range of Kemp's ridleys is limited for the most part to the gulf of Mexico where
adult forge for crabs. their favorite is blue crabs that share the same habitat as
shrimp. So ridleys sea turtle is often caught in shrimp ne