Group Title: United States Virgin Islands animal fact sheets
Title: Leatherback sea turtle
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Permanent Link: http://ufdc.ufl.edu/UF00093446/00003
 Material Information
Title: Leatherback sea turtle
Series Title: United States Virgin Islands animal fact sheets
Physical Description: Book
Language: English
Creator: Division of Fish and Wildlife, Department of Planning and Natural Resources, United States Virgin Islands
Publisher: Division of Fish and Wildlife, Department of Planning and Natural Resources, United States Virgin Islands
Place of Publication: St. Thomas, VI
 Record Information
Bibliographic ID: UF00093446
Volume ID: VID00003
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.

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Department of Planning and Natural Resources
Di\ ision of Fish and Wildlife
U.S.V.I. Animal Fact Sheet #03

Leatherback Sea Turtle
Dermochelys coriacea


Taxonomy
Kingdom
Phylum
Subphylum
Class
Order
Family
Genus
Species

Identification Characteri
* Foreflippers
* Size
* Upper jaw
* Carapace
* Rear carapace
* Color (dorsal)


Animalia
Chordata
Vertebrata
Reptilia
Chelonii
Dermochelyidae
Derrmochelys
coriacea

istics
very large, no claws
large (to > 1,000 lbs)
2 fang-like projections
rubbery tissue (no shell)
ends in a blunt point
black with white spots


Description
The leatherback sea turtle (Dermochelys coriacea) is
the largest of the sea turtles. These giant air breathing
reptiles may weigh over 600 kg (1,320 pounds). The
shell on their back, which is called the carapace may be
over 180 cm (almost 6 feet) long. Normally, our only
opportunity to closely examine living leatherbacks
occurs during their nesting season, when females come
ashore, and hatchlings leave.
Aside from its large size, the leatherback is unique
among sea turtles in several other respects. Adult
leatherbacks do not have scutes (scales) covering their
carapace as in other sea turtles. Instead, the leatherback
carapace is comprised of a thick (- 4 cm, 1.5") flexible
black skin that resembles rubber or leather [hence the
name]. The oil-saturated skin provides the turtle with
insulation in cold water, allowing them to feed in the
cold North Atlantic waters. There are seven ridges that
run the length of the body which form a blunt point near
the tail.
The front flippers of the leatherback are
proportionally much longer (up to one meter long) than
those of the other sea turtles. Leatherbacks have two
fang-like projections on their upper jaw to help retain
soft-bodied prey.
Adult leatherbacks are white on their bellies and
black on the carapace, however their black coloration is
broken up by many white spots. Hatchlings lack the
white spots. However the black color is interrupted by


seven white stripes running along the ridges. Their skin
appears dimpled, with tiny bead-like scales which are
later lost as they grow. Hatchlings are large compared to
other sea turtles, averaging 6.1 cm (2.5 inches) carapace
length and weighing about 45 grams.

Distribution & Habitat
Leatherbacks occur in all the worlds' oceans and are
capable of migrating over 3,000 miles. Their nesting
areas all occur in tropical and subtropical areas, but
feeding areas may extend well into cold temperate
waters for example off Iceland or Canada.
Much of leatherback behavior remains a mystery.
During adulthood, they spend almost their entire lives in
the deep waters of the open ocean (known as the pelagic
zone) and, aside from nesting periods, they are rarely
encountered in coastal waters. Almost nothing is known
of leatherback distribution from post-hatching through
sub-adulthood. However, in the past decade two
juvenile leatherbacks have been found in the Virgin
Islands such encounters are helping biologists
understand the movements and behavior of this species.
Leatherback sea turtles also visit cold waters in
pursuit of food. They are capable of diving to over
3,300 feet where water temperatures may fall below 6C
(43F). To cope with extremes of temperature and
depth, leatherback sea turtles have evolved a suite of
physiological and morphological adaptations; their
peculiar body form allows for their unusual lifestyle.


A' N X







Diet
The diet of most marine turtles is poorly understood
and leatherbacks are no exception. Most evidence
indicates that adults and juveniles feed almost
exclusively on gelatinous organisms (especially
jellyfish). The specialized structures in their mouths and
throats appear to help leatherbacks capture/retain soft-
bodied prey. In captivity, hatchlings will feed
voraciously on jellyfish, eating up to twice their own
body weight per day. Nonetheless, jellyfish are a poor
nutritional source, (the tissue is mostly water) and it is
unclear how leatherbacks can reach their tremendous
size on such a diet.

Reproduction
We are fortunate to have the largest leatherback
nesting site in the United States located at Sandy Point
National Wildlife Refuge on St. Croix. Females usually
select large sandy beaches with easy access to deep
waters for nesting, and Sandy Point is an ideal habitat.
Peak nesting season is from March through July, and
nesting almost always takes place at night.
Nesting females drag themselves up the beach using
their front flippers, leaving behind a large and distinctive
track in the sand. They first sweep away loose dry sand
to form a large shallow depression (a process called
body pitting). They then use their rear flippers to scoop
out a hole, alternating between left and right flippers and
flinging sand forward over their head. When the nest is
deep enough, they proceed to lay approximately 80 eggs.
They will try to disguise their nests after the eggs have
been laid.
Adult female leatherbacks migrate to nesting sites
every 2-3 years. During a single season, females will
nest every 9-10 days, laying between 5-7 clutches.

Conservation
The U.S. Fish and Wildlife Service lists the
leatherback as globally endangered. It is also listed by
CITES (Convention on International Trade of
Endangered Species) under Appendix I the most
endangered of the CITES-listed animals and plants -
which prohibits all international trade in this species. In
the U.S.V.I., Federal and territorial law prohibits
harvesting adults or eggs of all sea turtle species.
Pollution and commercial fishing impact
leatherbacks. Leatherbacks will mistake pieces of
floating plastic for food, becoming entangled and may
starve or suffocate. Commercial fishing gears
(longlines, gillnets) can entangle leatherbacks, leading to
injury or drowning.
Destruction and modification of nesting habitat also
represent a significant threat to leatherback sea turtles.
Beach erosion, poaching and lighting have reduced
nesting success, accelerating the decline of leatherback


populations. In the Pacific Ocean leatherback turtles are
in serious decline, and may becoming locally extinct.
We are very fortunate that on St. Croix we have an
internationally renown program to study, monitor and
protect our local population of leatherbacks. Since 1980,
teams of researchers, locals and Earthwatch volunteers
have participated in this project. This project is the
longest and largest continuous research and monitoring
project for leatherback sea turtles in the world. Since the
start of the project in 1980 the numbers of leatherback
sea turtles nesting on the beach has gone from 20 per
year to nearly 200 per year. A great deal of information
has been gathered and we continue to collaborate with
researchers world wide to learn more about these
magnificent animals.

What you can do to help
1. If you see any turtle nesting or hatching events, please
write down the date, time and location you saw the turtles
then call the Division of Fish and Wildlife at 340-772-
1955 (on St. Croix) or 340-775-6762 on St. Thomas/St.
John to report the event.
2. Hatchlings can crawl to the water themselves, if you see
hatchlings making their way into the water, please let
them complete the journey themselves.
3. Please make an extra effort to keep plastic out of the
marine environment.
4. Turtles, especially hatchlings, will head toward the
brightest light source on the beach. This used to be star
and moon light shining on the ocean, but today it may be
street or building lights. If possible turn off lights that
shine on and toward the beach, when hatchlings are
emerging.
5. Do not take flash pictures or shine lights directly toward
the turtles it will disorient them. Like us, turtle eyes will
maintain the ghost image of the flash, only the hatchlings
see this as a bright area and will crawl toward it.
6. If hatchlings emerge during the day, you may protect
them from predators, and guide them to the waters edge.
7. If you see a nesting turtle do not crowd around it and do
not harass it. You may observe nesting from a distance.
Be sure to stay behind the front flippers of the turtle so
that you do not disturb her. No flash photography.
8. Occasionally turtles will nest during the day. If you see a
daytime nesting sea turtle, please call the Division of Fish
and Wildlife immediately.
9. For more information on this and other animals in the
Virgin Islands please visit our web site at:
www.vifishandwildlife.com
BY WILLIAM COLES AND WES TOLLER, 2003
THIS PUBLICATION WAS PRODUCED WITH FUNDS
FROM THE WILDLIFE CONSERVATION AND
RESTORATION PROGRAM (WCRP).
FOR MORE INFORMATION ON
ANIMALS OF THE U.S.V.I., CONTACT
THE DIVISION OF FISH AND WILDLIFE
6291 ESTATE NAZARETH, 101, ST. THOMAS, VI 00802
PHONE 340-775-6762 FAX 340-775-3972
OR
45 MARS HILL, ST. CROIX, VI 00840
PHONE 340-772-1955 FAX 340-772-3227




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