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Captive rescued adult from the Gulf of Mexico. Sea Turtle Rescue Center, Sea Turtle Inc., South Padre Island, Texas. |
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Adult underwater, Brooklyn Aquarium |
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Habitat in California, the Pacific Ocean |
| Description |
| Size |
The largest hard-shelled turtle on earth. Adults are generally 33.5 - 39 inches in shell length (85 - 100 cm) and weigh around 300 lbs. (135 kg). The maximum known length is 7 ft. (213 cm), and turtles weighing 1,000 lbs. (453 kg.) have been reported. (These are old records and turtles of this size probably no longer exist.)
In our area, most Loggerheads are around 8 - 36 inches in shell length (20.3 - 91 cm). (Stebbins 2003) |
| Appearance |
A large marine turtle with a very broad head, a thick, bony, elongated heart-shaped shell, and huge paddlelike limbs. The carapace is high in front, and contains 5 or more costal shields on each side which do not overlap. The posterior rim is serrated. The first shield touches the nuchal shield. There are 2 pairs of pre-frontal scales.
The carapace is reddish or orange-brown, with yellow edging around the shields. The plastron is cream colored with some dusky clouding. The head pigmentation varies from reddish to olive brown, with many yellow-bordered scales. The flippers are rusty brown.
Males have a wider shell, a long tail that extends well beyond the edge of the shell, a recurved claw on each forelimb, and more yellow color on the head. Young have a yellowish carapace with 3 lengthwise keels. |
| Behavior and Natural History |
Aquatic, sometimes found far out in the open ocean. Hatchlings float and cannot sink. Hatchlings and juveniles are usually found drifting with ocean currents and eddies associated with drifting mats of marine vegetation.
Loggerheads spend much time floating on the surface sleeping and basking, but also rest submerged on the bottom.
During a year when she reproduces, the activity of a female Loggerhead can be divided into four periods - foraging (most of the year), migration to the nesting area, nesting, and migration back to the feeding range. In other years she will probably spend all year foraging in her feeding range.
Females usually return to the beach where they were hatched to nest several times during their lives, often traveling over a thousand miles to get there. How they manage to navigate such long distances to such a specific area is a mystery. This navigation might involve a combination of light cues, sound, smell, and an ability to detect the earth's magnetic fields. |
| Diet |
| Omnivorous. Invertebrates are the most important food group for Loggerheads. Their large head and massive jaws are adapted for crushing hard-shelled prey. Loggerheads eat sponges, crustaceans, mollusks, jellyfish, worms, cephalopods, bivalves, barnacles, shrimp, fish, and marine plants. |
| Reproduction |
Adults are sexually mature at between 10 and 30 years of age and can reproduce for up to 32 years.
Unlike all other marine turtles, Loggerheads nest on beaches mostly outside of the tropics. Nesting locations include Mexico, Braziil, Japan, South Africa, Oman, Australia, and the southeastern United States, from New Jersey to Texas, mostly in South Carolina, Georgia, and Florida.
Nesting occurs generally from May to August. The average female nests every 2 or 3 years, and sometimes up to 7 years. Females nest from 1 - 7 times per season (usually 1 - 3). Egg clutches are laid at intervals of around 11 - 15 days, in-between which a female may swim to reefs or estuaries to feed.
Most nests are dug at night, but diurnal nesting does occur. Wide beaches with a moderately-steep slope are preferred. The female Loggerhead crawls onto the beach then wanders around to find a proper nesting location. Then she digs the nest, lays around 125 eggs, then crawls back into the water. The whole process takes an hour or two.
Eggs are subject to predation by many animals, including crabs, crows, armadillos, raccoons, dogs, cats, skunks, snakes, and humans. The eggs hatch in 46 - 80 days. Hatchlings emerge at night and crawl frantically to the sea, dodging many predators which are waiting to eat them, which can include crows, snakes, crabs, vultures, seabirds, raccoons and dogs. |
| Range |
Loggerheads are found throughout temperate regions around the world in the Pacific, Indian, and Atlantic oceans, and the Mediterranean and Caribbean seas.
On the Pacific coast they are found from near Santa Cruz Island south to Chile. They are occasionally seen farther north.
California sightings are rare. Most are juveniles that have crossed Pacific Ocean after hatching on beaches in Japan. (Stebbins 2003) Sightings tend to occur from July to September and but may occur much of the year during El Niño years when ocean temperatures rise. Locations where Loggerheads have been seen in California waters include off Newport in Orange County, San Clemente Island, near Paradise Cove at Malibu in Los Angeles County, False Cape in Humboldt County, near West Anacapa Island, Montecito in Santa Barbara County, and San Diego and Camp Pendleton in San Diego County. |
| Habitat |
| Pelagic, living in the open ocean and rarely coming onto land. Enters coastal bays, lagoons, salt marshes, estuaries, creeks, and the mouths of large rivers. |
| Taxonomic Notes |
Two subspecies were once recognized - Caretta caretta caretta - Atlantic Loggerhead, and
Caretta caretta gigas - Pacific Loggerhead, but these subspecies are now considered invalid. |
| Conservation Issues (Conservation Status) |
Endangered.
The most populous sea turtle in North American waters, but their numbers are declining.
Development and degradation of beaches and coastal islands has destroyed nesting beaches or interfered with nesting activities. Artificial lights on beaches may cause females to return to the ocean without laying eggs. Hatchlings disoriented by the lights sometimes crawl toward highways and get run over. Nesting success is decreased due an increase in nest predators such as racoons which thrive in response to human development. Adults sometimes drown in shrimp nets or get killed by boat traffic. Floating plastic bags and balloons which resemble jellyfish are also a problem. When eaten, they block the gastrointestinal tract eventually killing the turtle. Entanglement in discarded fishing nets is also a serious threat. |
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Taxonomy |
| Family |
Cheloniidae |
Sea Turtles |
| Genus |
Caretta |
Loggerhead Sea Turtles |
Species
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caretta |
Loggerhead Sea Turtle |
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Original Description |
Caretta caretta - (Linnaeus, 1758) - Syst. Nat., 10th ed., Vol. 1, p. 197
from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
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Meaning of the Scientific Name |
Caretta - Spanish - carey - type of turtle and Latin -etta - little
from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz
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Alternate Names |
Loggerhead
Caretta caretta gigas - Pacific Loggerhead
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Related or Similar California Turtles |
C. mydas - Green Sea Turtle
E. i. bissa - Pacific Hawksbill Sea Turtle
L. olivacea - Olive Ridley Sea Turtle
D. coriacea - Leatherback Sea Turtle
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More Information and References |
Natureserve Explorer
California Dept. of Fish and Game
Turtles.org
Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.
Behler, John L., & F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.
Bartlett, R. D. & Patricia P. Bartlett. Guide and Reference to the Turtles and Lizards of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009.
Carr, Archie. Handbook of Turtles: The Turtles of the United States, Canada, and Baja California. Cornell University Press, 1969.
Ernst, Carl H., Roger W. Barbour, & Jeffrey E. Lovich. Turtles of the United States and Canada. Smithsonian Institution 1994.
Lemm, Jeffrey. Field Guide to Amphibians and Reptiles of the San Diego Region (California Natural History Guides). University of California Press, 2006.
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The following status listings come from the Special Animals List which is published several times each year by the California Department of Fish and Game.
This turtle is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California, however it is endangered worldwide.
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Organization
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Status Listing
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| U.S. Endangered Species Act (ESA) |
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| California Endangered Species Act (CESA) |
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| California Department of Fish and Game |
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| Bureau of Land Management |
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| USDA Forest Service |
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| Natureserve Global Conservation Status Ranks |
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World Conservation Union - IUCN Red List
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