TL: SEA TURTLES (GP)
SO: Greenpeace USA and NZ 
DT: Spring 1989
Keywords: oceans turtles factsheets reptiles greenpeace groups gp
endangered species /

     Sea turtles have inhabited the earth for over 100 million 
years. Today seven species of these ocean dwelling reptiles remain.
Once inhabiting marshes, they evolved and adapted for life in the
sea, the female returning to shore only to lay her eggs. Sea
turtles are found throughout the world in tropical and sub-tropical
oceans. Most species are highly migratory, often passing through
territorial and international waters from feeding to nesting
grounds and back again.
     Sea turtles are air breathing reptiles, varying in size
according to species and maturity. They are well adapted for life
in the sea, being able to dive for long periods, swim powerfully
and survive without fresh water. They are protected against most
natural predators in the water by their size, shell and bony skull.
     Sea turtles do not have teeth but their jaws can crush, tear
or bite depending on their diet, which varies between species.
There is little reliable information on their lifespan, but they
are generally assumed to be long-lived, greater than 50 years for
larger animals. Until maturity is reached it is difficult to
distinguish between male and female turtles. At maturity, the male
develops a long tail and often a curled and elongated claw on each
fore-flipper.
     Generally, the only time sea turtles leave the protective
habitat of the ocean is when the female crawls ashore to nest. Some
sea turtles return to the same stretch of beach, usually every two
to three years, nesting several times in a season. Under cover of
darkness,the female drags her large body by her flippers a few
inches at a time towards an area above the high tide mark. After
carefully digging a precisely shaped hole with her rear flippers,
she deposits between 60 and 200 eggs,the number varying between
species. While laying, she 'weeps' tears which excrete salt from
her body and wash the sand from her eyes. Once completed, she
covers the eggs and disguises the nest, throwing sand behind her
with her flippers. Afterwards she
returns to the ocean, leaving the eggs to incubate in the sand and
the future hatchlings to fend for themselves.
     Many eggs are lost to predators, inundation, erosion, or are
infertile. After an incubation period of approximately two
months, the hatchlings break out of their shells and over a few
days dig their way to the surface. Almost always at night under the
cover of darkness, they emerge from the nest and then, guided by
the light of the moon and stars on the water, they scramble
instinctively towards the ocean. A significant number may be eaten
by birds, crabs and other predators. Upon reaching the sea, little
is known about their fate or destination until, when mature, the
females come ashore to nest. It is estimated that only one in every
1,000 survives to adulthood.

Threats To Sea Turtles

Commercial Exploitation

Commercial exploitation has resulted in the depletion and decline
of sea turtle populations all over the world. In the Caribbean, a
number of large green turtle populations were so heavily
exploited that they became commercially extinct by the early 1800s.
In Mexico, populations of olive ridleys also crashed after they
were overexploited for their skins.
     Today, sea turtles continue to suffer exploitation
throughout their range and during their entire life cycle. Adults
are harpooned or speared in the water and females are flipped over
onto their backs and killed while coming ashore to nest. The meat,
especially from the green turtle, is a favoured food of many
coastal peoples. Turtle flippers are used for leather
products such as wallets and shoes. Sea turtle oil is also used for
skin lotions and cosmetics. Turtle shell, predominantly from the
hawksbill, is made into tortoiseshell jewellery. Some shells are
also ground up for cattle feed. Nests are also plundered for eggs
which are eaten locally or exported. Even the hatchlings, while
racing to the safety of the ocean, are caught and moulded in
plastic to be used as paper weights and other curios.
     International trade in all these turtle products continues to
be lucrative. Often, as turtle populations become depleted in one
area, commercial exploitation shifts to another. Furthermore, the
introduction of cash economies based on sea turtles and the growth
of coastal communities is placing increasing pressure on sea turtle
populations. Pacific peoples have been exploiting turtles for
subsistence purposes for thousands of years. However, in recent
times the motive of some hunting has become commercial rather than
traditional, with the sale of shell in particular commanding high
prices in export markets. The increase in killing for commercial
reasons is further threatening the depleted
populations of sea turtles.
     Despite an international prohibition on trade in sea turtle
products under the Convention on International Trade in
Endangered Species (CITES), no animal listed under the Convention
is traded more often (or in such huge volume) as sea turtles. Since
1976, there has been a substantial trade of sea turtle shell,
averaging 60 tonnes of tortoiseshell being exported per year,
worldwide. The major exporters of sea turtle shell are Indonesia,
Maldives, Cuba, Haiti and Jamaica. Substantial
quantities also come from the Pacific, in particular the Solomon
Islands and Fiji. Many of these countries are also laundering
points for shell collected from neighbouring areas. The major
importer of turtle shell is Japan, but there are also large shell
carving industries in Singapore, Taiwan, Hong Kong and China.

Types Of Sea Turtles

Worldwide, there are seven species of sea turtles. All except one
(Kemp's ridley turtle) are found throughout the Pacific region. The
most frequently occurring species in the Pacific are the hawksbill
and green turtles although the leatherback, loggerhead and olive
ridley turtles also occur. The flatback is endemic to Australia.

Hawksbill Turtle (Eretmochelys imbricata)

Hawksbill turtles inhabit tropical coastal waters around coral
reefs. They are small turtles, adults commonly weighing around 50
kg, are up to 90cm in length and are named after their narrow,
birdlike beak. Whilst sporadic nesting occurs throughout the
tropical Pacific, the major known nesting sites in the Pacific are
in Torres Strait (between Australia and Papua New Guinea) and the
Solomon Islands. Hawksbills nest high up the beach, often in
vegetation. The hatchlings are 40-45mm in length and are dark all
over. The hawksbill turtle is omnivorous, consuming a variety of
items including seagrasses, jellyfish, sponges and crustaceans. The
multi-coloured shell of the hawksbill is the source of what is
known as tortoiseshell, which is highly valued for jewellery and
other luxury items.

Green Turtle (Chelonia mydas)

Green turtles are found in the Atlantic, Pacific and Indian oceans,
primarily in tropical regions. Green turtles have an oval, greenish
carapace (shell) with darker streaks and can weigh up to 230 kg
with an average length of 1 metre. Although
hatchlings are mainly carnivorous, adult green turtles are
predominantly herbivorous, feeding on seaweed and seagrasses.
Worldwide the major nesting grounds are in Australia, Indonesia,
Ascension Island and Costa Rica. Limited nesting occurs
throughout the Pacific. Green nests are identified by a deep body
pit and a large amount of sand thrown back. Hatchlings are about
50mm in length and have a black carapace and white plastron (belly
shell). Turtle meat for human consumption is most
frequently obtained from greens.

Leatherback Turtle (Dermochelys coriacea)

The leatherback turtle is the largest of all turtles, reaching a
length of 1.8 metres and weighing up to 600 kg. This circumglobal
species inhabits the high seas in the Atlantic, Indian and
Pacific oceans and occasionally the Mediterranean. The
leatherback is ecologically unique among sea turtles. Unlike the
other species, it lacks a hard outer shell but instead has a soft
shell composed of small bones and cartilage which is
characterized by seven long ridges. The leatherback's diet
consists mostly of jellyfish. Leatherbacks are also known to travel
almost 5000 kilometres from nesting to feeding grounds. Worldwide,
nesting occurs on tropical and sub-tropical beaches in Mexico,
Central and South America, South America and Surinam. In the
Pacific, most nesting occurs in Papua New Guinea and some other
Pacific islands.

Loggerhead Turtle (Caretta caretta)

Loggerhead turtles are also highly migratory animals and nest
further from the tropics than other turtle species. They grow to a
length of about 1 metre and weigh up to 180 kg. They have a brown,
heartshaped carapace, a large head and a hard, horny beak.
Loggerhead turtles are primarily carnivorous, feeding on
molluscs, crabs, jellyfish and crustaceans. Worldwide, the major
nesting grounds are in Oman, southeastern U.S. (around Florida) and
eastern Australia. Loggerheads nest sporadically throughout the
Pacific, but the major nesting site in the region is in eastern
Australia. Loggerhead nests are characterised by a
shallow body pit and small amounts of sand thrown back.
Hatchlings are 50mm in length and light to dark brown, with a
lighter plastron.

Olive ridley Turtle (Lepidochelys olivacea)

The olive ridley turtle is the smallest of the sea turtles -adults
weighing less than 40 kg, measuring 65cm in length - and is found
mainly in the tropical Pacific and Indian oceans. They are mostly
carnivorous, eating crustaceans, fish eggs and some vegetation. The
major nesting sites worldwide are in Mexico, India and Costa Rica.
There are no known major rookeries in the Pacific, but some low
density nesting does occur. The major characteristic of the olive
ridley is their habit of nesting in congregations called
"arribazones", when thousands of female turtles will emerge
together over a few nights.

Flatback Turtle (Natator depressa)

The flatback turtle is a large turtle found only in northern
Australian waters and the Gulf of Papua. Nesting occurs
exclusively in Australia and the major feeding grounds are the Gulf
of Carpentaria and the coastal waters sheltered by the Great
Barrier Reef. The flatback has a dark carapace, weighs up to 80 kg
and feeds on invertebrates. Hatchlings are about 70mm in length and
have a distinctive carapace pattern.

Kemp's ridley Turtle (Lepidochelys kempi)

The Kemp's ridley turtle is a close relative of the olive ridley
and is the most endangered species of sea turtles. They are small
carnivorous turtles weighing up to 45 kg, grow to a length of 65cm
and have a grey circular shell. It feeds on crabs and
molluscs. The Kemp's ridley is found only in the Gulf of Mexico and
along the U.S. Atlantic coast. There is only one important nesting
site in the world, in Mexico. Of an estimated 40,000 nesting
females in 1947, less than 500 survive today and some experts
believe that the species may be beyond recovery. Female Kemp's
ridleys also nest together en masse but despite their last major
nesting beach in Mexico being fully protected, past
"arribazones" provided an easy opportunity for overexploitation by
humans.

     Many of the countries now trading in sea turtle shell are
parties to CITES, and it appears that much of the shell exported is
in contravention of the CITES prohibitions. Unfortunately, some
nations such as Japan, have refused to abide by the CITES
agreements to halt the trade. In addition, several important turtle
exporting nations such as the Solomon Islands and Fiji, have yet to
become parties to CITES.

Habitat Destruction and Alteration

Throughout the world human activities have been increasingly
intrusive on both nesting and foraging habitats of sea turtles.
Widespread coastal development has had several negative impacts on
sea turtles. In some areas, serious beach erosion has resulted from
inappropriate development and developers have built all types of
structures on beaches where female turtles lay their eggs.
Alterations of beaches severely reduce the chances of successful
nesting by sea turtles. For example, construction of breakwaters
can prevent females from nesting above the high tide mark,
resulting in their nests being washed away. Even removal of
vegetation or an increase in shade on a beach can alter nest
temperatures, reducing hatchling success and affecting hatchling
sex ratios. Nests are also destroyed by vehicle and foot traffic,
and by beach cleaning devices.
     Artificial light from development may reduce the numbers of
females coming ashore to nest. It also causes disorientation of
newly hatched turtles drawing them away from the ocean. By
instinct, hatchlings focus on the brightest area, and on many
beaches artificial light streams from nearby roads and buildings.
Thousands of hatchlings die each year when they scramble in the
wrong direction. They fall prey to predators, are crushed on roads
or die of dehydration.
     In addition, the destruction of coral reefs can threaten
turtles by adversely affecting their foraging and breeding
habitats.

Fisheries Interactions

Around the world, thousands of sea turtles drown each year as a
result of interactions with fishing fleets. Turtles are often
killed in driftnets, in pound nets and on the hooks of
longliners, but the largest mortality is caused by shrimp/prawn
trawlers. All sea turtle species, especially the loggerhead, have
been found dead in shrimp/prawn nets. It is estimated that over
47,000 sea turtles are caught each year by the U.S. shrimp
fishery, of which approximately 12,600 die.
     Fortunately, a solution to this problem has been found. A net
modification called a Turtle Excluder Device (TED) has been
developed and is 97% effective in releasing sea turtles caught
during trawling. In the U.S., regulations for the mandatory use of
the TED came into force in 1989, but there are many fishermen
reluctant to use them. The incidental take of turtles in
shrimp/prawn trawling is not solely restricted to the U.S.
Appreciable numbers of turtles are caught in prawn fisheries in
Australia, but there is little information available on the
incidental kills of turtles in other areas of the Pacific.

Marine Debris/Pollution

Sea turtles are particularly vulnerable to plastics. Like other
marine species, sea turtles become entangled and subsequently die
in lost or discarded monofilament fishing nets. Ingestion of
plastics is also a severe problem. Certain species of sea turtles
are nondiscriminatory feeders and will eat anything in their
environment which resembles food. Turtles may mistake floating
plastic for a jellyfish, which once eaten becomes clogged in their
digestive tract. It has been estimated that almost half of the
oceanic turtles have eaten plastic.
     Sea turtles are also extremely vulnerable to oil and toxic
chemical pollution. Immature turtles have been found dead with
their throats and jaws obstructed by tar. There is also evidence
that toxic chemicals in the oceans may cause mortality and
injury, sensory disruption, and reduced reproductive success.

Ineffectual Protection

A fundamental problem for sea turtle conservation is that most
countries do not have the will or resources to adequately protect
sea turtles. Many sea turtle species are protected by national
legislation which is often rendered ineffectual because of lack of
enforcement. Where legislation is in place, it usually has followed
the pattern of traditional fishery protection which attempts to
protect younger animals. However, with turtles the most valuable
members of the population for the survival of the species are the
breeding adults.
     Therefore, where laws allow turtles to be killed for
cultural reasons, lawmakers must set maximum size limits above
which turtles are protected. Furthermore, due to the migratory
nature of most sea turtles, concerted regional action is required
to make any legislation and protection measures effective. In the
Pacific, cooperation efforts need to be made through the South
Pacific Forum and its associated bodies (e.g. South Pacific
Regional Environment Programme or SPREP) to increase protection for
sea turtles within the region.

Greenpeace Action

Greenpeace is working worldwide to encourage further protection of
sea turtles through national and international conservation laws,
eliminating trade in sea turtle products, implementing nesting
beach management and curbing fisheries and pollution impacts on
turtles. In addition to working throughout the
Caribbean, U.S. and Mediterranean, Greenpeace is now researching
and exposing the problems facing sea turtles in the Asia Pacific
region. In collaboration with government authorities and local
groups, Greenpeace is working to increase public awareness of the
threats to turtles and is encouraging Pacific nations to increase
protection. Greenpeace is also attempting to halt the export
tortoiseshell trade in the Pacific, from countries such as the
Solomon Islands and Fiji.
     Efforts are also being made to encourage regional
cooperation on turtle conservation in the Pacific through SPREP and
to promote implementation of the International Union for the
Conservation of Nature (IUCN) Sea Turtle Resolution. This
resolution prepared by Greenpeace and adopted by IUCN's General
Assembly in 1988, calls on governments to: prevent the killing of
breeding adults, restrict or halt the collection of turtle eggs,
cease all international trade in turtle products, promote the use
of TEDs and protect turtle habitats, particularly. nesting
beaches and coral reefs.

GREENPEACE Pacific Campaign

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