Loggerhead Sea Turtle

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Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Subclass:	Anapsida
Order:	Testudines
Family:	Cheloniidae
Genus:	Caretta Rafinesque, 1814
Species:	C. caretta

Binomial name

Caretta caretta
Linnaeus, 1758

The Loggerhead Sea Turtle (Caretta caretta) is a sea turtle and the only member of the genus Caretta. The genus name "Caretta" is a latinization of the French "caret", meaning turtle, tortoise, or sea turtle^[1]. A loggerhead sea turtle reportedly grows up to 800 lbs (364 kg) and 3.5 feet long.^[2] Their shell color is a reddish brown color, and the color of their skin is brown yellow.

1 Ecology and life history
- 1.1 Trophic ecology
- 1.2 Life history
2 Etymology and taxonomic history
3 Importance to humans
4 Conservation
5 See also
6 References
7 Bibliography
8 External links

[edit] Ecology and life history

[edit] Trophic ecology

The species feeds on mollusks, crustaceans, fish, jellyfish, and other small to medium-size marine animals, which they crush with their large and powerful jaws. As with other sea turtles, females return to lay their eggs on or near the same beach where they hatched. Unlike other sea turtles, courtship and mating usually do not take place near the nesting beach, but rather along the migration routes between feeding and breeding grounds.

[edit] Life history

Baby Loggerhead Sea Turtle.

Loggerhead Sea Turtle laying eggs.

In the Mediterranean, Loggerheads mate from late March to early June. The female nesting season is at its peak in June and July, but this depends on the nesting beach. The clutch may vary from 100 to 126 eggs. Each egg is roughly the size and shape of a golf ball. The average interval between nesting seasons is two to three years.

Loggerheads are the most common sea turtle to nest in the United States. With the largest concentration of nests in south Florida, they nest from Texas to Virginia to North Carolina, requiring soft sandy beaches, where there is little light; although statistics collected in Florida since 1998 indicate the lowest nesting levels Florida has seen in 17 years, where nesting rates have declined from 85,988 nests in 1998 to approximately 45,084 in 2007. ^[3]

After approximately 60 days, the hatchlings emerge usually at night when protection from predation is greater. Usually following the brightest light to the ocean's edge, an artificial light, such as from a home can lead them astray. Once in the ocean they use ocean currents to travel to the Sargasso Sea using the Sargassum as protection until they mature^{[citation needed]}.

An alternative to migration for many loggerheads is hibernation to varying degrees as the water cools. By February they are submerged for up to seven hours at a time, emerging for only seven minutes to recover. Although outdone by freshwater turtles, these are the longest recorded dives for any air-breathing marine vertebrate^[4].

Most loggerheads that reach adulthood live for longer than 30 years, and can often live past 200 years. They are immune to the toxins of a Portuguese Man O' War as the turtles have often been seen feeding on them.

[edit] Etymology and taxonomic history

Two subspecies are recognized: Caretta caretta gigas, is found in the Indian and Pacific Oceans, and C. caretta caretta, the Atlantic loggerhead, also found in south Italy and the Greek islands of Zakynthos, Kefalonia, Crete and the Peloponese and in Dalyan in southwestern Turkey. (see article; June Haimoff).

[edit] Importance to humans

Loggerhead Sea Turtles were once intensively hunted for their meat and eggs, along with their fat which was used in cosmetics and medication. The Loggerhead Sea Turtles were also killed for their shells, which are used to make items such as combs. As a result both subspecies are now internationally protected.

[edit] Conservation

Loggerhead Sea Turtle escapes from fishing net through a TED (Turtle Excluder Device).

Today the main threat to the adult loggerheads lies in shrimp trawls and crab fishing nets, to which many loggerheads annually fall victim. Furthermore, adults are often injured by speedboat propellers and by swallowing fishing hooks or getting caught in nets. Internationally animal protection organizations take pains to monitor and protect the turtles' nesting grounds in Turkey,^[5] Greece, Bonaire and Costa Rica. The turtles can also be found around the Italian islands of Lampedusa and Linosa, off the coast of Sicily, and in Calabria, where it is particularly endangered. Furthermore, the turtles are known to nest on the beaches of the Northern part of Cyprus, especially Alagadi Beach.^[6]

Loggerhead Sea Turtle nest roped off as part of the Sea Turtle Protection Project on Hilton Head Island

In many places during the nesting season workers search the coastline to find evidence of nests. Once found a nest will be uncovered and the eggs carefully counted, if the nest is dangerously located the eggs will be moved to a better spot. Plastic fencing will be placed at or near the surface to protect the eggs from large predators such as raccoons or even dogs. The barrier used is large enough to allow the hatchlings to emerge without difficulty. The nests are checked daily for disturbances, several days after there is indication that the eggs have hatched the nest will be uncovered and the tally of hatched eggs, undeveloped eggs, and dead hatchlings will be recorded. If any hatchlings are found, they are either taken to be raised and released, or taken to research facilities. Ones that appear strong and healthy may instead be released to the ocean. Typically those that lacked the strength to hatch and climb to the surface by that point would have died otherwise.

Hatchlings require the travel from their nest to the ocean in order to build up strength for the journey ahead, so interfering by helping it to the ocean actually lowers their chances of survival.