Red: Some approximate spots where Leatherback Sea Turles have been recorded.
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| Adult female laying eggs on the beach with turtle researchers, Guanacaste, Costa Rica. © William Flaxington. |
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Leatherback tracks on beach, Guanacaste, Costa Rica. © William Flaxington. |
Pacific Ocean, San Mateo County, near the site of a Leatherback sighting. |
| Many of the sightings of Leatherbacks in California waters occur from whale-watching or pelagic birding boats, where the occupants are carefully scanning the water for wildlife. Below are links to some pictures of Leatherbacks taken from boats off the California coast. |
| Shearwater Journeys |
Monterey Bay |
Don Roberson |
| Description |
Size |
The largest turtle on Earth, growing to the size of a small automobile.
Adults average 48 - 96 inches in shell length (122 - 244 cm). 600 - 1,600 lbs, possibly as much as a ton. (Stebbins 2003) |
| Appearance |
A huge marine turtle with smooth leathery skin, a large head, paddle-like clawless limbs, no scales or claws, and an elongated, triangular carapace with 7 prominent lenghthwise keels that lacks a rigid shell of horny scutes. Many small bony platelets embedded in the skin make up the carapace which is not connected to the ribs or the backbone.
Color is dark brown, slate, or blue-black and either unmarked or with pale blotches. The skin on the head, neck, and limbs is black or dark brown with some white spotting. The plastron is gray or black, with 5 ridges.
Young have many small scales, a rudderlike tail, and a thin, high dorsal keel. Their flippers are edged with white.
Males have a tail that is longer than the hind limbs, and a concave plastron. Females tend to have a lot of pink on the head. |
| Behavior and Natural History |
Leatherback Sea Turtles are an ancient lineage over 70 million years old that outlived the mass extinction that killed the dinosaurs. Little is known about their behavior in the wild. They are sometimes found in large groups, especially around large schools of jellyfish.
Leatherbacks are capable of diving to great depths on one breath. They are also capable of swimming and feeding in cold waters due to their ability to keep their internal temperature higher than the ambient temperature.
Leatherbacks are thoroughly aquatic and very powerful swimmers, often swimming great distances far out to sea as they follow drifting flotillas of jellyfish.
*Research since 2001 has discovered that the Leatherbacks found on the west coast of North America are part of the genetic stock as those that nest in Indonesia, Papua New Guinea and the Solomon Islands. The Central Coast of California, including Monterey Bay, is one stop in the seasonal migration of Leatherbacks in the Pacific as they travel across the ocean from the western Pacific to feed on jellyfish, especially brown sea nettles. Scott Benson, marine ecologist for National Oceanic and Atmospheric Administration at the Southwest Fisheries Science Center, has captured, tagged, and released leatherbacks in Monterey Bay and Indonesia and tracked them as they cross the ocean. He discovered that they arrive in California waters in June where they stay until mid October when they move to waters off Hawaii. They return to California the following summer, and they may repeat this journey two or three times before they are ready to swim all the way to the nesting beaches in Indonesia.
*(Source: Lily Dayton, Monterey County Herald, 7/19/2009.) |
| Diet |
| Carnivorous, eating mainly jellyfish, but also consuming some plant matter such as kelp and algae and other invertebrates and vertebrates, including sea urchins, snails, octopi, squid, crabs, and small fish. Feeds on the surface and below. |
| Reproduction |
Leatherbacks breed in the open ocean, but where exactly is not known. It may occur off the nesting beaches after migration, or it may occur before or during migration.
Nesting along the Pacific coast takes place usually from September through March, most frequently in November and December. The main nesting beaches in the Pacific are Mexico, Costa Rica, and Indonesia, but most Leatherbacks found in California waters come from beaches in Indonesia. In the United States, nesting occurs on beaches in Florida and Georgia, and formerly in Texas.
Females return to a preferred nesting beach, most likely the beach from which they hatched. An individual female breeds every 2 - 3 years. Nesting beaches are sandy with a gradual slope and a deep water approach so the turtles can ride the waves high onto the beach.
A female leatherback climbs onto the nesting beach at night where she digs a deep nest with their hind feet and lays a clutch of 50 - 166 eggs (averaging 60 - 66 in the eastern Pacific) many of which are not viable, having no yolk. An average of 6 clutches per season is probably normal for a breeding female. She will return to the beach every 8 - 12 days to lay another clutch of eggs.
Egg mortality is high due to predation by humans and other animals. The eggs hatch in 60 - 65 days. Many young never reach the water due to attacks by predators, or they succumb to aquatic predators after they enter the water. Hatchlings emerge at night where they sometimes circle to get their bearings, then crawl quickly to the ocean where they swim continuously for the first day. After the young enter the ocean they are seldom seen along the coast. |
| Range |
The Leatherback is the most widely-distributed sea turtle, with the largest geographic distribution, ranging all over the world. Found mostly in tropical waters, they move into temperate waters during the summer. They have been recorded from cold waters in places such as Norway, Iceland, and Alaska.
Most sightings in California occur from boats out at sea. Locations where Leatherbacks have been observed in California include north of Del Mar, San Diego County, off San Clemente and Santa Rosa islands, north of Jalama Beach and south of Santa Barbara Harbor, Santa Barbara County, the mouth of the Ventura River and a mile east of Emma Wood State Beach in Ventura County, Monterey Bay, the north end of Pigeon Pt. Beach in San Mateo County, and southeast of Santa Cruz, Santa Cruz County. |
| Habitat |
| Pelagic, living in the open ocean and occasionally entering the shallower water of bays and estuaries. |
| Taxonomic Notes |
Two subspecies have been described - Dermochelys coriacea schlegelii - Pacific Leatherback, and
Dermochelys coriacea coriacea - Atlantic Leatherback. A third subspecies that occurs off the west coast of the Americas has also been suggested, but these races are so poorly differentiated that they are no longer accepted by many herpetologists. |
| Conservation Issues (Conservation Status) |
Critically endangered. Undergoing a rapid decline.
Some reasons for the decline include harvesting of their eggs, degradation of nesting beaches, mortality from longline, drift, and set gill-net fishing and discarded fishing nets, and the accidental consumption of floating plastic bags and balloons which resemble their preferred jellyfish prey. The indigestible plastic blocks the gastrointestinal tract eventually killing the turtle. (Think about that next time you consider buying a large balloon or using plastic shopping bags!) Offshore boat traffic is also a serious threat when the boats move so quickly that the turtles cannot swim out of their way in time to avoid collision.
Leatherback eggs are widely consumed, but the flesh is not generally eaten. The flesh can store toxins from jellyfish and become poisonous. Human deaths have been reported after consumption of Leatherback meat. |
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Taxonomy |
| Family |
Dermochelyidae |
Leatherback Sea Turtles |
| Genus |
Dermochelys |
Leatherback Sea Turtle |
Species
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coriacea |
Leatherback Sea Turtle |
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Original Description |
Dermochelys coriacea - (Vandelli, 1761) - Epistola de Holothurio, et Testudine coriacea ad celeberrimum Carolum Linnaeum Equitum Naturae Curiosum Dioscorcidem II. Conzatti, Patavii (Padova). 12 pp.
from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
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Meaning of the Scientific Name |
Dermochelys - Greek - derma - skin, and chelys - turtle - refers to soft skin covering the shell
coriacea - Latin - corium - leather, and -acea - having the nature or color of - refers to the leathery carapace
from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz
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Alternate Names |
luth
Dermochelys coriacea schlegelii - Pacific Leatherback
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Related or Similar California Turtles |
C. caretta - Loggerhead Sea Turtle
C. mydas - Green Sea Turtle
E. i. bissa - Pacific Hawksbill Sea Turtle
L. olivacea - Olive Ridley Sea Turtle
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More Information and References |
Natureserve Explorer
California Dept. of Fish and Game
National Oceanic and Atmospheric Administration Fisheries Office of Protected Resources
Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.
Behler, John L., and F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.
Powell, Robert., Joseph T. Collins, and Errol D. Hooper Jr. A Key to Amphibians and Reptiles of the Continental United States and Canada. The University Press of Kansas, 1998.
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 is a mistake, as it is listed as federally Endangered on the California Department of Fish and Game Endangered and Threatened Animals of California list.
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Organization
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Status Listing
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| U.S. Endangered Species Act (ESA) |
FE |
Endangered |
| 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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