Divitinr f iRah an1M] Wildlffel
U.S.V.I. Animal Fact Sheet #24
Introduced Species and Sea Turtles
Photographs of a green turtle whose eyes were chewed out by dogs, while attempting to nest.
Exotic species are plants or animals that are
introduced into any area to which they are not native.
An exotic species becomes invasive once it begins to
reproduce and is likely to cause economic or
environmental harm or harm human health. Invasive
species can be plants, insects, animals, or diseases.
Invasive species often reshape the environment in
which they have been introduced. They may even
make the local habitat uninhabitable by any other
organism but the specific invasive species. One of the
main reasons an introduced species becomes invasive
is the lack of natural predators in their new
The lack of natural predators may allow the
introduced organism to go through a population
explosion. A population explosion occurs when a
species multiplies at an uncontrolled rate because the
rate of mortality has decreased (there is no predation).
Many invasive species are accidentally introduced.
Rats, fire ants, tan-tan, Cuban tree frogs and acacia are
some local examples of accidental introductions.
Some introduced species came to the islands as pets
(dogs, cats, pythons, red eared sliders) livestock
(goats, pigs, cows), ornamental plants (blood grass,
water lettuce, coral vine) and subsequently were
abandoned, escaped or were unintentionally released
due to hurricanes, fires or deaths of the owners.
Other introductions have been intentional.
Locally our major intentionally introduced species are
the mongoose, cane toad, and white tailed deer. Of
these the mongoose has created the biggest
environmental disturbance. Their impact has been felt
by all ground dwelling animals in the territory.
Mongoose are generally diurnal animals (active
during the day). However, those who live along the
beaches have become nocturnal, at least during the
turtle nesting season. Mongoose have become a
major predator of sea turtle hatchlings and eggs.
Perhaps the greatest sea turtle predators are the
feral dogs and cats on the islands. They will eat the
eggs and hatchlings but will also attack the adults. In
the last three years we have been receiving increasing
numbers of calls from people about dogs attacking
turtles nesting on the beach. Sea turtles spend almost
their entire lives swimming in the ocean, and have
developed special adaptations to allow them to remain
at sea. These adaptations make sea turtles extremely
graceful and agile while in the water but ungainly on
land. While nesting, they are not agile or fast enough
to avoid these introduced predators. They are unable
to pull their heads and flippers into their shell like
tortoises, which makes them very vulnerable to attack
by terrestrial predators.
Virtually all the documented damage to nesting
turtles has been to the head and neck region of the
turtle, as you can see in the pictures. Rarely has any
damage been documented to the flippers or carapace
of the turtle. It is important to realize that the dogs
may attack not only turtles but possibly small children
playing on the beach as well.
This hawksbill was also attacked by dogs. It had hunched its
head down and had the back of its neck torn out.
These animals have enough trouble with natural
threats. On land nests wash away during incubation,
ants and crabs invade nests, and birds eat hatchlings as
they emerge from nests. In the water fish eat
hatchlings and juveniles, while sharks and killer
whales prey on adults (we estimate that for every
1000 eggs laid one turtle may survive to adulthood
and reproduce). To add human stressors to the
equation is too great a burden for the species. We
need to take extra effort to keep our domestic animals
from attacking our turtles.
All sea turtles are protected by Territorial, Federal
and International laws and treaties, which have been
instituted to attempt to protect threatened and
endangered species so that their populations can
increase to a point where they no longer need
protection to sustain their natural population levels.
WHAT YOU NEED TO KNOW
* Sea turtles do not have an effective way to avoid
predation on land. They can't pull their heads and
flippers into their shell. This makes them easy
prey for introduced predators.
Any dog found running at night may be seized,
impounded and disposed of(VIC: Title 19, Chap.
66, 2615). You can and will be held liable for
the death of any endangered species caused by
Do not discard unwanted pets. Take them to the
Humane Society. They can cause extensive
damage to our already fragile island ecosystem.
You may not harass or kill sea turtles under ANY
Turtles are easily disoriented by lights. When they
are on the beach do not take flash pictures or shine
lights directly toward the sea turtles.
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 Sea Turtle Assistance
and Rescue (STAR) network 1-878-1TURTLE.
2. Contact STAR or 911 if you find a turtle being
attacked by animals.
3. Neuter or spay your dogs and cats and keep them
under your control at all times.
4. If you see someone harassing a sea turtle or
poaching a nest, call the local police (911) or the
local Division of Environmental Enforcement STT
340-774-3320, STX 340-773-5774.
5. For more information on this and other animals in
the Virgin Islands please visit our web site at:
PRODUCED IN 2005 by W. Coles
WITH FUNDS FROM THE NATIONAL FISH AND
WILDLIFE FOUNDATION (NFWF).
FOR MORE INFORMATION ON
OUR NATIVE ANIMALS CONTACT
DIVISION OF FISH AND WILDLIFE
6291 ESTATE NAZARETH
ST. THOMAS, VI 00802-1118
PHONE 340-775-6762 FAX 340-775-3972
45 MARS HILL, ST. CROIX, VI 00840
PHONF 3-A-777 -19Q5 FAY XA-777-3777