Download Marine Turtles in the Wild

Marine Turtles
in the Wild
by Elizabeth Kemf, Brian Groombridge, Alberto Abreu, and Alison Wilson
2000 – A WWF SPECIES STATUS REPORT
2
Executive Summary
4
Turtles through Time
6
Natural History of Turtles
14
Threats and Issues
20
What WWF has done for Marine Turtles
28
What WWF is doing for Marine Turtles
38
What Needs to be Done
The material and the geographical designations in this report do not imply the expression of any opinion whatsoever on the part of WWF
concerning the legal status of any country, territory, or area, or concerning the delimitation of its frontiers or boundaries.
About the authors:
Elizabeth Kemf is Species Conservation Information Manager for WWF International and
co-author and editor of WWF's species status reports.
Brian Groombridge is Compiler and Co-editor of the 1996/IUCN Red List of Threatened Animals,
Species Survival Commission.
Alberto Abreu is Chairman of the IUCN/SSC Marine Turtle Specialist Group.
Alison Wilson is a biologist and independent science writer and a frequent contributor to
and co-author of WWF's species status reports.
Conservation Editor: Marydele Donnelly, Programme Officer of the IUCN/SSC Marine Turtle Specialist Group.
Designed and produced by: Saatchi & Saatchi Advertising.
Published April 2000 by WWF – World Wide Fund For Nature (formerly World Wildlife Fund), Gland, Switzerland.
Any reproduction in full or in part of this publication must mention the title and credit the above-mentioned publisher as the copyright owner.
© text 2000 WWF. All rights reserved.
EXECUTIVE SUMMARY
xecutive
summary
2
Marine turtles are fascinating creatures that have lived on
the earth for over 100 million years. Some early fossil
records date back 230 million years. This remarkable reptile,
of which there are seven species, is revered in culture and
custom around the globe. It symbolises longevity, fertility,
strength and protection from harm. From the Aboriginal
people of Australia and their neighbours in Asia and the
Pacific to coastal communities of Africa, Central, South
America and Europe, the turtle has held a place of special
importance. In some creation myths it is believed to be the
animal on whose back the world was created.
The largest ever turtle, Archelon ischyros, lived during
the Cretaceous Period, over 65 million years ago, and
reached around 3.5m in length. Evidence from archaeological excavations shows that turtles were hunted by humans
long before written records were kept. Today, the largest
turtle is the leatherback and one of the largest living reptiles.
Leatherbacks grow to impressive sizes, up to 180 cm long
and weigh about 500 kg. The largest leatherback ever
recorded, an enormous male that stranded on a beach in
Wales, UK in 1988, was 256 cm in length and weighed
nearly a ton.
Turtles have always attracted attention, whether laying
their eggs on beaches or hatching from shells and making a
mad dash to the surf in the first minutes of life. Scuba divers,
snorkellers and lucky swimmers who glimpse them by
chance underwater thrill to the sight. No matter how idolized the turtle may have been, or still is, it has been exploited
for centuries as a source of food, decoration and commerce.
Because of overuse and other threats – including pollution,
accidental drowning in fishing nets or hooking by longline
fishing and habitat loss – six of the world’s seven marine
turtles are in danger of extinction. The hawksbill and
Kemp’s ridley have been classified by the IUCN/SSC
Marine Turtle Specialist Group as “Critically Endangered”.
All seven species are listed on Appendix I of the Convention
on International Trade in Endangered Species of Wild
Fauna and Flora (CITES), thus prohibiting international
trade in them by more than 140 CITES member nations.
Decorative tortoiseshell, from the carapace of the
hawksbill turtle, has been traded over long distances since at
least the time of the pharaohs, and certain Red Sea ports
flourished on the basis of this trade. Some say that Cleopatra’s bathtub was fabricated from tortoiseshell. (Parsons
1972) They were also a prominent feature of the earliest
known coins, referred to as “turtles” in the slang of the day,
minted in the Greek state of Aegina from 700 BC onwards.
Demand for tortoiseshell remains high, especially in
Japan and other parts of East and South and Southeast Asia,
and two countries, Cuba and Dominica, have proposed that
the international trade in the hawksbill turtle be reopened.
WWF opposes the resumption of trafficking in this and
the other six species of marine turtles. Many populations
EXECUTIVE SUMMARY
2000 WWF Species Status Report
ing beaches. Erosion, accretion, sand mining, and foot and
vehicular traffic also need to be addressed on nesting
beaches to ensure that nesting females, eggs and hatchlings
are protected. Long-term monitoring programmes are also
critical to assessing the impact on these habitats.
For many populations of marine turtles around the
world, the day-to-day support of local coastal communities
is crucial to their survival. In some areas the turtle is a valuable source of nourishment and ecotourism income. If the
marine or sea turtle vanishes, the world will lose not only a
long-treasured symbol, it will also witness the disappearance
of a species that has roamed the earth for hundreds of
millions of years.
Green turtle hatchling.
Upon leaving the nest, green,
hawksbill and loggerhead
turtles rush to the surf and
then to the open ocean where
they spend several years
before returning to their
“home” beach.
WWF/ANDREAS DEMETIOPOLOS
that were abundant 100 to 200 years ago are now depleted,
declining or remnants of their former size. Local extinctions
have occurred in all ocean basins, and no population, not
even those that are stable as a result of long-term conservation and management, is completely safe. Numbers of
nesting marine turtles (of four species) in Malaysia have
fallen drastically in recent decades, with leatherback nests
declining by 98 per cent since the 1950s.
After the shrimp trawl fishery was identified as a major
source of mortality in the early 1980s, net inserts or Turtle
Excluder Devices (TEDs) were developed to allow
entrapped turtles (and other bycatch) to escape. Although
TEDs are used widely in the western hemisphere, they are
not employed extensively in shrimp and other trawl fisheries
around the world. Mortality in longline fisheries for pelagic
species such as swordfish and tuna is also a grave and
increasing threat. These fisheries, which set billions of hooks
each year, continue to expand. Marine turtles swallow longline hooks or become
entangled in lines and
drown. Many animals that
are released alive, but with
hooks embedded in their
bodies, usually die. Marine
turtles are also captured and
drowned in various gill net fisheries and in the lines of fish traps.
Programmes to reduce mortality
through modified gear and fishing
techniques, or closing particular areas
at particular times, are needed; fishermen should be encouraged to assist in
these efforts.
In recent years powerful new tools, such as
genetic analysis and satellite telemetry, have been
developed to answer the riddles surrounding
marine turtles, but much remains to be discovered, and much needs to be done.
Marine turtle conservation requirements
should be included in coastal zone
management plans as well as ecosystem conservation programmes.
Regulations for maintaining water
quality and contingency plans for
oil and chemical spills are critical to
maintain the health and productivity of the ecosystems on which
marine turtle depend. The threats
posed by dynamite fishing, marine
debris, and oil pollution should
be eliminated. Where necessary,
legislation must be encouraged,
such as lighting restrictions on nest-
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TURTLES THROUGH TIME
History and Culture
urtles
through
time
Ancient Greek coins like this replica were
used as money and known then as
“turtles”. Now it is the symbol of the Sea
Turtle Protection Society of Greece.
4
The symbol of the turtle is universally revered in culture and
custom around the world. It represents longevity, fertility,
strength and protection from harm. From the aboriginal
people of Australia to the coastal communities of Africa,
such as the Bajuni people of Kenya, the turtle holds an
important place in their lives. In some creation myths it is
believed to be the animal on whose back the world was created. For example, among the Hurons and the Iroquois of
North America, the “Legend of the Woman Who Fell From
the Sky” describes how the earth was formed. A woman
lived in the upper world before the earth was formed.
“There was nothing but water, nothing but a wide, wide sea.
The only people in the world were the animals that lived in
and on water. Then down from the sky a woman fell, a divine
person.”(Clark 1979) The legend varies as to which birds,
ducks or loons, flew beneath her, catching her as she plunged
into the darkness and saved her from drowning. But all variations of this myth say that it was the Great Turtle who
asked that she be placed on his back. Around his back earth
was placed, where plants and trees could grow, “and it is yet
today that the Great Turtle still bears the earth on his
back”. (Ibid)
Among Hindus, the second incarnation of the god
Vishnu was as a turtle. After a great flood, various gods tried
to raise the earth. Vishnu transformed himself into a turtle
and upon his back he lifted up the earth and saved it from
the powerful waters. (Pritchard 1990) In Hindu
belief, the tortoise or turtle supports the elephant,
which in turn supports the earth. Temples and
shrines all over the world honour all kinds of
turtles, those that live in the sea and in fresh
water, as well as tortoises that live on land.
The turtle in India has long been considered
as holy, while in neighbouring Bangladesh
there is a Muslim temple where the custom
of caring for the turtles has survived for
centuries. In the city of Chittagong, people
worship and look after the black three-clawed
softshell turtle, a species of freshwater turtle
found nowhere else in the world (Pritchard 1990). A
stone tablet recently discovered in Taiwan, dated 1883,
tells a story of how 18 wealthy philanthropists worked
together in the Chin Dynasty to protect baby girls, old cattle
and sea turtles.
The first known turtles are represented by fossil
material from the Late Triassic Epoch, some 230 million
years old. These ancient forms already show most of the
distinctive features of shell and skeleton characteristic of
turtles, and so the evolutionary affinities of the group are
quite obscure. Marine turtles, possibly descendants of
species that inhabited swamps and marshes during the Late
Triassic Epoch, evolved into their present familiar form
WWF/ELIZABETH KEMF
TURTLES THROUGH TIME
Marine turtle in Bali being prepared for ceremonial sacrifice. WWF is
working with spiritual and community leaders to find alternatives.
approximately 110 million years ago and have wandered the
planet’s oceans ever since. The largest ever turtle, Archelon
ischyros, lived during the Cretaceous Period, over 65 million
years ago, and reached around 3.5 m in length. Evidence
from archaeological excavations shows that turtles were
hunted by humans long before written records were kept.
In the tropical Pacific Islands the hawksbill is still considered sacred and in the Gilbert Islands turtles are used as
family totems. (Witzel 1983) According to the Mayas of
Central America, the God of the Moon is protected by a
breastplate of tortoiseshell. The nearby Tolteca people call
the celestial Shield of Orion, Thoh, which also means turtle
in their language. (Devaux 1991) Further north in the
United States, a more recent type of turtle reverence and
respect has sprung up. Thousands of people have joined turtle and tortoise clubs, whose members can follow the fate of
these much loved ancient creatures not only in the oceans
but also in newsletters and websites on the Internet.
However worshipped the turtle may have been or still
is, it was also exploited as a source of food, decoration and
commerce. Decorative tortoiseshell, from the carapace of
the hawksbill turtle, has been traded over long distances
since at least the time of the Pharaohs, and certain Red Sea
2000 WWF Species Status Report
ports flourished on the basis of this trade. In Nubia and
Egypt, many ancient graves have been found containing
ornaments fashioned from the carapace of turtles, known as
tortoiseshell. The English language term originates because
of the sea turtle shell’s similarity to the carapace of land
tortoises. Spanish (carey) and French (caret, écaille) words
are believed to originate from the language of the Arawak
peoples of the West Indies. (Parsons 1972)
Some say that Cleopatra’s bathtub was fabricated from
tortoiseshell. (Parsons 1972) Rome and India presented gifts
made from tortoiseshell to the Chinese Emperor. In Palau,
tortoiseshell from the hawksbill turtle was used for ceremonial “women’s money” (Witzell 1983). Turtles were also a
prominent feature of the earliest known coins, referred to as
“turtles” in the slang of the day, minted in the Greek state of
Aegina from 700 BC onwards.
By the 19th century international displays of tortoiseshell products were held in the UK, France, and the US. In
1852, manufacturing of combs for women’s hair was most
significant in Scotland and the State of Massachusetts in
the US. “Tortoiseshell, a 19th century British periodical
observed, was imported from more countries than any similar material.” (Parsons 1972) Today, all seven species of
marine or sea turtles are listed on Appendix I of CITES,
thus prohibiting trade in them by those countries who are
CITES member nations. However, demand for tortoiseshell
remains high, especially in Japan and other parts of East,
South and Southeast Asia. Accidental killing in longline
fishing and nets, continued trade, combined with overconsumption of turtle meat and eggs for subsistence,
commercial, and even ceremonial purposes, are threatening
this living legend with extinction.
5
NATURAL HISTORY OF TURTLES
atural
history
of turtles
WWF-CANNON/URS WOY
Loggerhead turtle.
6
There are relatively few marine reptiles of which sea turtles
are by far the most familiar. Others include sea snakes
(the largest group, containing about 50 species), a marine
iguana and one or two crocodilians that range into brackish
or coastal marine waters. There are seven living species of
marine turtle although the actual status of the east Pacific
green or black turtle remains uncertain. Arguments for and
against its designation as an eighth species are the subject
of ongoing debate. The family Dermochelyidae includes
the single species Dermochelys coriacea, the leatherback
turtle. The other six are placed in the family Cheloniidae:
(1) Caretta caretta, the loggerhead turtle, (2) Chelonia
mydas, the green turtle, (3) Eretmochelys imbricata, the
hawksbill turtle, (4) Lepidochelys kempii, Kemp’s ridley
turtle, (5) Lepidochelys olivacea, the olive ridley turtle, and
(6) Natator depressus, the flatback turtle. Although some
taxonomists have named and described marine turtle
subspecies, largely on the basis of colour and body proportion, these names are not in common use. There is now less
interest in morphological characteristics than in patterns
of genetic differentiation.
Five of the seven species
are found around the globe
(mainly in tropical and subtropical waters) while two
species have relatively restricted ranges: Kemp’s ridley occurs
mainly in the Gulf of Mexico
and the flatback turtle around
northern Australia and southern
New Guinea. Most species spend
much of their lives in continental
shelf waters, although leatherback
and olive ridley turtles tend to lead
more of their lives on the high seas.
Males do not leave the sea and females
only come ashore to lay their eggs on
sandy beaches during the appropriate
season. The first several years of life
are spent drifting in the open ocean,
with most time thereafter in coastal
feeding grounds.
During the nesting season,
mature males and females migrate from
feeding grounds and mate near the nesting beach. Females
mate with several males and store the sperm for repeated
fertilisation of eggs without the need for further mating.
A female turtle typically crawls out of the water and up
the beach at night to lay many eggs, often more than 100, in
a single nest, returning to the water before dawn. On undisturbed beaches, she may repeat this process several more
times in a single nesting season, but will then spend the next
two years or so on the feeding grounds preparing for another
NATURAL HISTORY OF TURTLES
WWF/ELIZABETH KEMF
implication of this new information is that nesting colonies
require conservation management on an individual basis. A
depleted nesting population will not be replenished by
females from another population. Genetic evidence has also
demonstrated that feeding areas contain turtles from more
than one nesting population and not necessarily just from
the nearest nesting beach. This means that people in one
country might easily be harvesting turtles hatched in one or
more other countries, which serves to highlight the need for
international cooperation on turtle management.
Turtle researchers monitoring a nesting beach near Karachi, Pakistan.
2000 WWF Species Status Report
Turtle hunter with olive ridley.
PETER CH PRITCHARD
nesting migration. In the case of Lepidochelys species
(the two ridley turtles), huge numbers of turtles (sometimes
many thousands) may clamber ashore together over
a period of several days, a phenomenon known as an
arribada (arrival).
During a given season, an individual nesting female may
lay all her clutches within the same few square metres, showing high nest-site fidelity. Even more remarkably, females
have a strong tendency to return to nest on the same beach
on which they were hatched (high philopatry) as evidenced
by the fact that individual nesting aggregations tend to show
distinctive types of mitochondrial DNA, which is passed on
from mother to daughter in cell cytoplasm. This differentiation suggests that there is relatively low female gene flow
between nesting colonies.
The fact that another type of DNA (contained in cell
nuclei) does not vary in the same way suggests that there is
some exchange of genetic material between colonies. This
could be explained if males tend to mate with females from
different populations. An assumption that males are the
principal source of genetic exchange between colonies could
be explained if newly mature males are more interested in
finding a female with which to mate, than in the location of
the beach to which the pair eventually migrates. Feeding
areas are used by turtles from different populations, so such
a mechanism is feasible.
Although there is a rapidly growing body of genetic evidence, its interpretation is not always straightforward, as not
all marine turtles in all oceans share this basic pattern.
Leatherbacks, for example, colonise new beaches as they
appear in some areas of the tropics and researchers have
documented the use of adjacent beaches by individual green
turtles in the waters of Australia. However, the key practical
7
NATURAL HISTORY OF TURTLES
Hatchings
The eggs are completely unprotected once the mother
returns to the sea. Eggs incubate for 55 to 75 days, depending on the temperature. The size and weight of hatchlings
correlate with egg size. Like many reptiles, the sex of the
hatchling turtles is dependent on the temperature in the
nests, with cooler temperatures favouring the development
of males, and warmth favouring females.
Although successful hatching rates may reach 80 per
cent, there may be high predation, for example by mongooses, ghost crabs, rats, racoons, jackals, feral pigs and
dogs, to mention just a few. In many parts of the world turtle eggs are prized by humans as a rich source of protein, and
are often reputed to have aphrodisiac properties. Consequently all accessible nests may be stripped of their eggs. In
other cases, nests may be located below the high tide mark,
resulting in the destruction of many clutches by seawater.
The hatchlings tunnel out of the nests usually, but not
always, at night. Aligning themselves with the main source
of light, which in undisturbed situations will be the marine
horizon, they rush to the surf. At beaches altered by human
development, artificial light often attracts hatchlings inland,
where they are vulnerable to predators and road traffic, and
in any case soon desiccate. Where people and turtles co-exist
along developed beaches, shaded low-intensity yellow lighting can much reduce this problem. During the frenzied dash
to the water, hatchlings may suffer intense predation, especially if emerging during the day. At this size they are of limited interest to humans, but birds, mammals and crabs feast
on this bonanza, with few hatchlings reaching the surf. Once
in the water, the hatchlings head towards the incoming
waves and out to sea, where they still face a high risk of predation from birds and large fish such as groupers, snappers
and barracudas.
The survivors disperse into pelagic waters and spend
several years at sea. Some species do not return to coastal
waters until full sexual maturity, others do so as large juveniles. This period at sea, which can last up to a decade, is
commonly referred to as the “lost years” and is the least well
understood part of any turtle species’ life history. Recently,
however, some hatchlings have been tracked for considerable periods of time. Presumably turtles are less vulnerable
to predation by birds and some fish while in deeper waters.
Once they have grown sufficiently large to avoid such
attacks, the turtles are really only consumed by sharks, killer
whales (occasionally) and, of course, humans.
The broad reproductive strategy of marine turtles is to
spend a very long time developing to sexual maturity – perhaps 20 to 30 years on average, longer in cold nutrient-poor
areas – and then devote enormous resources to producing
large numbers of eggs several times during a nesting season.
The worth of any individual egg or hatchling, in terms of its
likelihood of contributing to population persistence, is very
8
Leatherback hatchlings rushing to the surf in French Guyana.
low indeed, while the worth of an adult or large subadult is
extremely high. In this situation, the loss of a small proportion of egg output from a beach is unlikely to have severe
consequences. At the other extreme, the practice of directly
harvesting nesting females from a beach is likely to have
enormous impact on the population.
Humans take turtles principally for their meat, shells
(carapace), and fat. Turtles are particularly vulnerable to
predation by humans because of the ease with which they
can be captured. Collecting the eggs from a nest is as easy as
digging a hole and filling a bucket. Females are incredibly
vulnerable when they come ashore to nest and adults are
readily tracked by fishermen because they swim slowly, have
to come to the surface to breathe, and are highly visible from
boats as they swim through clear tropical waters. They are
harpooned, netted or simply seized by divers.
Turtles have frequently been sighted far out to sea,
sometimes travelling in large aggregations, and are capable
of covering considerable distances. Studies in which turtles
have been tracked using satellite positioning technology
NATURAL HISTORY OF TURTLES
WWF-CANON/ROGER LEGUEN
in areas of open sea, and there are relatively frequent observations in temperate waters, and sometimes in brackish
lagoons and estuaries.
Mating occurs in open water, and – unlike in other
species – often takes place some way from the shore. The
major Atlantic nesting grounds are off the Coast of Florida
and South Carolina. Loggerheads are also the most common
turtle in the Mediterranean, with nesting reported from
Greece and Turkey to Israel, Tunisia, and Libya. Northern
Natal and Masirah Island, Oman, are the main nesting sites
in the Indian Ocean, and nesting occurs throughout Southeast Asia to Australia, but rarely in the central and western
Pacific islands. Females lay between 40 and 190 eggs per
clutch (average is about 100) and larger females tend to lay
larger eggs. The loggerhead is classified by the SSC Marine
Turtle Specialist Group as “Endangered”
have confirmed that they undertake enormous huge migrations, many thousands of kilometres, during their lives.
Recently, a female turtle tracked by satellite across the
Pacific had travelled 7,000km before contact was lost. Many
females forage over large geographical areas yet return to
the same beach to nest, navigating by a series of cues.
FAMILY CHELONIIDAE
Loggerhead (Caretta caretta)
Loggerheads are among the biggest cheloniid turtles, sometimes measuring well over a metre in shell length, weighing
up to 180 kg, and having characteristically large heads and
strong jaws. They are carnivorous throughout their lives, eating bottom-dwelling molluscs (conch, clams), crabs, urchins
and sponges, as well as free-swimming jellyfish. Loggerheads
are widely distributed in coastal tropical and subtropical
waters, and travel large distances following major warm
currents such as the Gulf Stream and California Current.
Solitary adults and groups of juveniles may be encountered
2000 WWF Species Status Report
Green turtle (Chelonia mydas)
So called because of the colour of the cartilage and fat
deposits around its internal organs, green turtles are dark
black-brown or greenish yellow. At up to 1.5m in length, the
green turtle is the largest cheloniid turtle. Scientists note that
individuals from Hawaii and the eastern Pacific are particularly dark in colour, and sometimes call it the black turtle.
The largest female green turtles are found in the Atlantic
and western Pacific Ocean, less in the Indian Ocean and the
Caribbean. The smallest is found in Guyana (80cm); weight
ranges between 90 and 200 kg. The carapace is oval when
viewed from above, and the head is relatively small and
blunt. Green turtles are widely distributed in the tropics, particularly near continental coasts and around islands, and
have been recorded in temperate waters. The only herbivorous marine turtle, the species feeds mainly on seagrasses,
flowering plants which grow in shallow coastal waters,
mainly in the tropics and subtropics. Females migrate huge
distances between the feeding grounds and nesting beaches.
Nesting occurs widely throughout the range, even on the
central Pacific islands, where few other turtles now occur.
Female green turtles sometimes show strong nest site fixity.
An individual nests about once every three years, and lays
between two to five clutches of 40 to 200 eggs, which develop
for 50 to 70 days before hatching.
An estimated 100,000 green turtles are killed around the
Indo-Australian archipelago each year. There is a near total
egg harvest in several countries, e.g. Thailand and Malaysia
(although egg production in Sarawak dropped from
2,200,000 eggs in the mid-1930s to 175,000 in 1995) and
disease threatens populations elsewhere. As a result, populations are declining worldwide, with numbers in Indonesia
decreasing by tenfold since the 1940s, and by more than half
in French Polynesia. The SSC Marine Turtle Specialist
Group has assessed this species as “Endangered”. Recovery
has occurred under strong conservation management
9
NATURAL HISTORY OF TURTLES
regimes, but only in a very few cases (e.g. Sabah Turtle
Islands National Park in Malaysia and Florida USA).
TABLE 1. CONSERVATION STATUS OF
MARINE TURTLES
Species/Common Name
Status
Caretta caretta
(loggerhead turtle)
Chelonia mydas
(green turtle)
Eretmochelys imbricata
(hawksbill turtle)
Lepidochelys kempii
(Kemp’s ridley turtle)
Lepidochelys olivacea
(olive ridley turtle)
Demachelys coriacea
(leatherback turtle)
Natator depressus
(flatback turtle)
EN
EN
CR
CR
EN
EN
V
EN - Endangered
CR - Critically Endangered
V - Vulnerable
Source: IUCN/SSC Marine Turtle Specialist Group
Hawksbill (Eretmochelys imbricata)
A medium-sized cheloniid that grows to about 90 cm in
length and weighs 60 kg on average, the hawksbill, as its
name suggests, has a narrow pointed beak reminiscent of a
bird of prey. The shell is highly coloured with elaborate patterns. The overlapping carapace scales are often streaked
and marbled with amber, yellow or brown, most evident
when the shell material is worked and polished. The hawksbill has a pan-tropical distribution and has only rarely been
recorded away from the tropics. It is the sole source of commercial tortoiseshell.
Nesting occurs widely throughout the range, but tends
to be more dispersed than in other species. There are few
major nesting colonies and only five sites have populations
with more than 1,000 females nesting annually. The hawksbill often nests on beaches close to coral reefs, and it is one
of the turtles most frequently encountered by scuba divers
over coral reefs. Female hawksbills nest every two or three
years, laying 60 to 200 eggs at a time. Sponges normally
10
constitute a major proportion of the diet. Hawksbill turtles
are carnivorous and use their narrow beaks to extract
invertebrate prey from reef crevices. Both sessile and mobile
animals are consumed.
Hawksbills have been hunted for centuries as a source
of tortoiseshell (“carey”) for jewellery and ornaments. In
recent decades eastern Asia, and Japan in particular, has
provided an eager market for tortoiseshell. Through international conventions and national legislation some countries
have sought with considerable success to restrict trade.
Japan was a major market for tortoiseshell until 1994. Cuba
has, in 2000, put forward a proposal to CITES, together with
Dominica, to reopen international trade, with Cuba selling
hawksbill shell to Japan. Harvest for domestic trade still
occurs in many countries, including Cuba, Dominica,
Indonesia, the Solomon Islands and Fiji. Because of the
strong evidence of significant worldwide decline and ongoing projected declines the hawksbill has been assessed by
the SSC Marine Turtle Specialist Group as “Critically
Endangered”. WWF rejects reopening the international
trade in hawksbill shell or “tortoiseshell”.
Kemp’s ridley (Lepidochelys kempii)
The two species in the genus Lepidochelys are the smallest of all marine turtles, reaching around 0.7m.
Kemp’s ridley has an almost completely round
carapace and four pores on either side of the lower surface. These are openings to glands, which release
pheromones important in the timing of mass nesting.
Kemp’s ridley turtle has been classified as “Critically Endangered”.
NATURAL HISTORY OF TURTLES
There was massive exploitation of eggs until this species
received protection in 1965. The nesting population crashed
from more than 40,000 turtles coming ashore in a single day
in the late 1940s to a few hundred females nesting in an
entire season in the late 1980s. As a result of an enormous
conservation effort to protect all nests produced at Rancho
Nuevo and required use of Turtle Excluder Devices (TEDs)
to reduce capture in fishing nets, the species is undergoing
a remarkable recovery. Because of documented decline,
Kemp’s ridley has been assessed by the SSC Marine Turtle
Specialist Group as “Critically Endangered”.
WWF-CANNON/URS WOY
The Kemp’s ridley turtle, is restricted to the Gulf of
Mexico and coastal waters of the western Atlantic Ocean of
the United States. This species prefers shallow sandy and
muddy habitats, such as the coastal lagoons of Louisiana,
Texas and Alabama; as a result, these turtles are usually
observed near to shore.
However it is neither size nor distribution that qualifies
Kemp’s ridley as something of an oddity amongst turtles; it
is its breeding behaviour. Nesting occurs conspicuously in
broad daylight, and apart from sporadic nesting elsewhere,
takes place only on one 20 km beach at Rancho Nuevo in
Mexico on the Gulf of Mexico. In the past, tens of thousands
of females nested simultaneously at the beach, a true
arribada. Nowadays arrivals are numbered in the hundreds.
Females lay an average of 1.5 clutches of 100 eggs
per season.
Kemp’s ridley turtles are carnivorous throughout their
lives, although the feeding behaviour of the hatchlings and
juveniles is very poorly understood. The adults consume
crabs, shrimps, clams and sea urchins and grow to 72 cm and
weigh 35 to 50kg.
2000 WWF Species Status Report
11
WWF-CANON/REY-MILLET
NATURAL HISTORY OF TURTLES
Freshly-laid turtle eggs in danger of collection are sometimes but not always protected.
Olive ridley (Lepidochelys olivacea)
The olive ridley turtle looks very similar to Kemp’s ridley,
but has a deeper body, with slightly upturned edges to the
carapace. It grows to about 72 cm, and weigh 35 to 50 kg.
However, the two Lepidochelys species have very different
distributions, with olive ridley absent from the Gulf of
Mexico and Florida, but present throughout the Antilles,
the north coast of South America, west Africa, the Indian
Ocean, Australia and Southeast Asia. Despite this wide
distribution, the species has only been observed around continents and large islands, where large flotillas are sometimes
observed moving between feeding and nesting grounds.
The main nesting beaches are on the eastern Pacific
coasts of Central America, from Mexico to Costa Rica, in
northeastern India, and Suriname. Sometimes the beaches
are separated from the mainland by coastal lagoons. In these
areas, thousands of females emerge from the sea and nest
simultaneously, over a period of two to three days. The
arribada is believed to be an adaptation against predation,
the predators being overwhelmed by numbers, and one
reason for the past success of this species. However, many of
the beaches are relatively small, less than 10 km long, and
nesting may be so dense that successive waves of females
often dig up previously laid nests in efforts to lay their own
eggs. Mass arrivals can be repeated (two to seven times a
season) and each female lays an average of 1.5 clutches each
year of nesting, of approximately 110 eggs, although this
can vary considerably. The species is typified by its wide
diet, consuming an enormous range of sessile and mobile
marine organisms.
12
With its documented decline and the continuing pressure
of incidental catch, beach development, and other factors,
the olive ridley has been assessed by the SSC Marine Turtle
Specialist Group as “Endangered”.
Flatback turtle (Natator depressus)
The flatback is a distinctive species, having a flat body and
smooth carapace with upturned edges. It has the most limited range of any turtle species, being found only around the
northern half of Australia, and in the seas between northern
Australia and southern parts of Indonesia and Papua New
Guinea. Flatbacks only very rarely leave the shallow waters
of the continental shelf, and nest only in northern Australia,
where beaches on small offshore islands are the most important sites. Nesting females coming ashore are sometimes
taken by crocodiles, possibly their major natural predator.
Very little is known about diet during the early stages of
development, but the species is believed to be predominantly carnivorous, with squid, sea cucumbers, soft corals,
and molluscs all being recorded in stomachs. Females grow
to about 100cm and weigh about 90kg.
The restricted range means that the flatback is
extremely vulnerable to habitat loss, especially of breeding
sites, but the major threat appears to be incidental catch by
the numerous fishing vessels operating in waters favoured by
these turtles. The species is not particularly valued by indigenous peoples and so is rarely subject to direct hunting; its
carnivorous diet is believed to be responsible for an unpleasant taste. Annual nesting populations range up to 10,000, but
long-term changes in this species are impossible to measure,
NATURAL HISTORY OF TURTLES
FAMILY DERMOCHELYIDAE
Leatherback turtle (Dermochelys coriacea)
The leatherback is the largest turtle and one of the largest
living reptiles. Leatherbacks grow to impressive sizes, up
to 180 cm and weigh about 500 kg. However, the largest
leatherback ever recorded, an enormous male which was
found stranded on a beach in Wales in 1988, was 256cm long
and weighed 916kg! Aside from their bulk, leatherbacks are
easily distinguished by their leathery-ridged carapace, lacking the horny plates (scutes) of other turtles. Leatherbacks
also have disproportionately long front flippers compared
to other turtles – they are at least half the length of the
carapace in adults.
This species has an unusually wide latitudinal range
as adults are able to withstand cold (10 °C) water. The
leatherback has been recorded north to Alaska and south to
the Cape of Good Hope and occurs regularly in waters off
New England, in the Bay of Biscay and off southeast Australia. It is a highly pelagic species, venturing close to shore
mainly during the nesting season, and is capable of diving to
several hundred metres. Adults feed mainly on pelagic softbodied creatures such as jellyfish and tunicates, which occur
in greatest concentrations at the surface in areas of upwelling
or convergence (see p.15 sections on Pollution and Bycatch).
2000 WWF Species Status Report
The regular appearance of leatherbacks in cool temperate
waters, e.g. in the northeast Atlantic, is probably due to the
seasonal occurrence there of large numbers of jellyfish.
The most important nesting areas are on the western
coasts of Mexico, Suriname and French Guyana, Malaysia,
Irian Jaya (Indonesia), and western Sumatra (Indonesia).
Female leatherbacks lay four to five times per season, each
time depositing 60 to 120 eggs. Strangely, a relatively large
proportion of eggs in each clutch are small and without yolk
and may serve as spacers for the nest.
The meat of this species is very oily and not particularly
favoured for human consumption. Worldwide population
declines, coupled with continuing pressures of egg harvest,
incidental catch and beach development have caused
the leatherback to be assessed by the SSC Marine Turtle
Specialist Group as “Endangered”.
PETER CH PRITCHARD
as most populations have never been monitored. This
species may be the least-threatened marine turtle, and has
been assessed as “Vulnerable” by the SSC Marine Turtle
Specialist Group.
Olive ridley shells outside a former
slaughterhouse in Mexico.
13
THREATS AND ISSUES
The Kemp’s ridley turtle was once the most common turtle
in the Gulf of Mexico, yet now it is critically endangered.
The extent and dramatic nature of this decline is evident
in old film footage of the 1947 arribada in which an estimated 40,000 females came ashore to nest in a single night.
Given that there may well have been two to three times
this number of females which did not lay that evening,
and perhaps an equal number of males far offshore, then
the population 50 years ago numbered a few hundred thousand. In 1985, just 200 females nested on Rancho Nuevo.
In recent years, Kemp’s ridley has been undergoing exponential recovery on the nesting beach after more than two
decades of protection and nearly ten years of Turtle
Excluder Devices.
What pressures could have produced such a collapse in
population numbers? The following is a summary of the
principal human impacts on turtle populations worldwide,
though different species are more or less vulnerable to
different pressures, in different locations.
hreats
and issues
PETER CH PRITCHARD
Direct consumption
Over collection of turtle eggs is threatening some marine turtle populations with extinction.
14
Turtles generally make good eating. Although the leatherback is less frequently consumed, and in some areas the flesh
of other species is considered unpalatable (e.g. Kemp’s
ridley turtles in Mexico) or even poisonous (e.g. hawksbill
turtles in parts of the Indo-Pacific), there is a long history of
human consumption. The high yield of good quality meat,
combined with the ease with which turtles can be caught, has
made them particularly desirable food items in coastal communities around the world. The green turtle quickly became
a dietary staple of colonial mariners and plantation owners
in the Caribbean from the late 16th century onwards; estimates suggest that tens of thousands were consumed annually in Grand Cayman, Jamaica and other parts of the West
Indies. As air-breathing animals, turtles can survive transportation by boat and overland, and they can also be kept
in holding enclosures for some time. As a result, from
the mid-18th century onwards turtle soup was produced in
London from animals shipped from the Caribbean, and this
international trade continued (albeit at a much reduced
scale) well into the 20th century. Green turtles in the
Mediterranean were almost extirpated by exploitation of
nesting females in the 1940s. Many other nesting populations
around the world were heavily depleted as consumption
pressures increased in parallel with coastal development,
human population increase, and breakdown of cultural
restraint on harvesting.
Turtle eggs are also easy to collect and highly nutritious.
As a result, the arrival of nesting females is traditionally
regarded as a predictable bounty, providing a welcome
change of diet. This allure is further enhanced by the aphrodisiac properties, which are frequently attributed to turtle
eggs, so much so that they are traded illegally.
D. ALLEN
THREATS AND ISSUES
Loggerhead turtle drowned in fishing net.
Turtles have also been hunted for their shells, which
are used in jewellery, and their hides, which are cured for
leather. There are recent reports of turtle-leather cowboy
boots being freely available in Tijuana, Mexico, and of
rooms full of confiscated boots on the US border. Though
trade in marine turtles is illegal under CITES, they are still
stuffed, varnished, mounted and sold openly as tourist curios
in Vietnam, Cambodia, Mexico and parts of the Caribbean.
Bycatch and longline fishing
An unknown quantity (some estimates are as high as 200,000
to 300,000 annually) of turtles are killed as “bycatch”
(i.e. incidentally), particularly in trawling nets. Decline was
set in motion by decades of egg collecting and the killing of
females; then it was continued by trawler mortality. This is
probably one of the major causes of decline in the Kemp’s
ridley turtle which is particularly vulnerable because it feeds
in the rich shrimping grounds of the Gulf of Mexico (see p.17
section on Turtle and shrimp fishing). Longlines for tuna and
swordfish are responsible for killing leatherback and loggerhead turtles, which are attracted to the baited hooks. The
turtles either become snared or tangled in the line and are
then unable to reach the surface and drown (or in some cases
lose a limb). Turtles that have swallowed hooks most
certainly die as well, although they may be released alive.
2000 WWF Species Status Report
This problem is particularly acute because these two species
feed on planktonic organisms that are found in highest concentrations along oceanic fronts, areas that also support the
highest densities of pelagic fish.
Habitat destruction and alteration
The construction of seawalls, hotels, marinas and the entire
infrastructure associated with coastal tourism and commerce
have destroyed large areas of turtle nesting beaches around
the world. Turtle reproductive behaviour evolved in an environment of deserted, intact beaches. Nowadays, light and
noise pollution frequently deter or interrupt many females
from successful laying. Hatchlings locate the water’s edge by
orientating themselves towards the horizon, but house and
street lights can disorient newly hatched turtles so that they
actually crawl away from the sea. Adult turtles are reported
as displaying symptoms of acute physiological stress in some
areas of very heavy coastal traffic, such as the Adriatic. It is
possible that these adults may be deterred from coming
ashore at all.
Pollution
Heavy metals including aluminium, arsenic, cadmium, copper, iron, mercury, selenium and zinc, have been recorded
in the tissues of stranded turtles, especially the kidneys and
15
THREATS AND ISSUES
liver. These metals were measured in concentrations sufficiently elevated to cause metal toxicity. Similarly, phthalate
esters, molecules used in the manufacture of plastics which
are known to be toxic and have mutagenic and carcinogenic
properties, have been identified in turtle eggs. The exact
effects of these and other substances on the reproductive
biology and health of turtles, and the implications for their
conservation, are unknown but surely negative.
There is no uncertainty as to the effects on turtles of
another type of marine pollutant, solid debris. Items as varied as tar balls, condoms, fishing line, plastic bags and bottles
have been found in the stomachs of all species in quantities
so great that normal nutrition must be impaired. Occasionally turtles make meals of spectacular objects such as the
3 x 4 m heavy plastic sheet (found in a loggerhead), or the
180 m monofilament line consumed by a leatherback – off
New York, United States. Such nondegradable items persist
in the ocean for years and if not eaten directly still pose a
danger to turtles through entanglement, which at best
impedes swimming and at worst leads to the loss of limbs,
choking or drowning (as is the case with drift nets used in
commercial fishing). The problem of ingestion of marine
debris and entanglement is particularly acute for new hatchlings during the first few years after birth (the “lost years”).
During this period they are pelagic, drifting with strong
oceanic currents and inevitably they are concentrated along
fronts where there is an abundant supply of both shelter
(sargassum weed) and pelagic prey. Scraps of plastic also
accumulate here and soon become encrusted with edible
bryozoans, barnacles and algae. This, and the fact that tar
balls and styrofoam pellets are the same size and shape as
sargassum floats, probably account for the misguided feeding on these items by young turtles.
Disease
Debilitating and disfiguring tumours have been identified
in numerous populations of turtles in the late 1970s,
although these abnormalities were first described in green
turtles in the 1930s. The prevalence of these tumours, called
fibropapillomas, which develop in a manner similar to warts
in humans, increased dramatically in the 1980s in Florida
and Hawaii where more than 50 per cent of some populations were found to be affected. Widespread problems
with fibropapillomas are a new phenomenon. Reports
involving the capture, handling, and sighting of thousands
of turtles by former turtle fishermen in Hawaii indicate
that tumours were virtually non-existent prior to the 1950s.
Although most commonly seen in Chelonia mydas (green
turtle), tumours have been found in loggerhead, olive
ridley, flatback and leatherback turtles as well. Up to 92
per cent of individuals can be infected in some areas, with
highest prevalence in shallow near-shore waters with relatively restricted water turnover. Many (but not all) of these
16
Green turtle with life-threatening tumours.
marine habitats are near areas of heavy human use and
terrestrial runoff.
Tumours can blind the turtles or inhibit their ability to
feed. Tumours may also develop internally in the lungs, liver,
kidney and gastrointestinal tract, resulting in flotation problems, bowel obstruction, kidney failure and pressure necrosis (death) of affected tissues. Affected turtles are generally
extremely emaciated, weak and anaemic, with severely
restricted eyesight, and are likely to die prematurely. Since
1983, 31 to 54 per cent of stranded green turtles in Hawaii
have been found to bear fibropapillomas. Although regressions of tumours have been reported recently, the prognosis
for most turtles with tumours is poor.
Although circumstantial evidence may suggest that pollutants could be a factor, studies have so far been unable to
find any unusual concentrations of pollutants in the afflicted
populations. It is possible that the disease is the result of a
combination of factors. Turtles under stress from pollution
could be more vulnerable to a virus that would otherwise be
relatively harmless.
DR SCHRICHTE
THREATS AND ISSUES
Turtles and shrimp fishing
Instead of swimming away from an approaching net, turtles
try to outswim the trawl but get caught once they tire. After
years of studying this problem, the US National Marine
Fisheries Services developed Turtle Excluder Devices
(TEDs) for use by commercial fishermen. TEDs are panels
of large mesh webbing or metal grids inserted as barriers
into the funnel–shaped shrimp nets. As the trawls are
dragged along the bottom, shrimps and other small animals
pass through the TED and into the narrow bag at the end of
the funnel where the catch is collected. Sea turtles, sharks,
and fish too large to get through the panel are deflected
out an escape hatch (the TED), reducing bycatch by up to
97 per cent.
Without TEDs sea turtles become trapped in a net for
as long as it is towed underwater and sometimes drown or
undergo physiological changes that result in death. Prior to
the required use of TEDs in the US, tens of thousands of sea
turtles drowned in shrimp nets each year.
2000 WWF Species Status Report
Although shrimp fishermen feared TEDs would cost the
shrimping industry millions of dollars in equipment and
lost catch, TEDs have proved successful in the United States
and elsewhere. They also reduce fuel costs by excluding
non-shrimp species that often outweigh shrimps by ten
to one and provide a better quality catch (the shrimps are
not crushed by other species).
However, the US government’s requirement for the use
of TEDs became one of the most bitterly fought regulations
in the history of fisheries management. Mexico and 13 other
Central and South American nations followed this lead,
mainly because under a 1989 law the US Department of
State banned the import of shrimps from any country not
taking adequate measures to conserve sea turtles in commercial shrimp fisheries. In 1988, 150,500 tonnes of shrimps
worth US$ 506 million were caught in US waters. The rest of
the 365,500 tonnes consumed that year were imported,
mainly from India, Indonesia, Thailand, Mexico, Malaysia,
Korea and Japan, all nations where turtles are under
serious threat.
Despite the benefits of using TEDs, some international
opposition remains. In 1997 four Asian countries – Thailand,
India, Malaysia and Pakistan – challenged the US decision
to ban shrimp imports from countries with inadequate
marine turtle conservation measures. The nations took the
case to a WTO dispute panel, which interprets WTO rules.
While the WTO has the power to suspend free trade rules
for conservation reasons, the panel ignored the relevant
international conservation agreements including the General Agreement on Tariffs and Trade (GATT) and ruled
that the US ban was illegal. After an appeal by the US, the
WTO finally acknowledged the potential of such a trade
restriction to protect the environment. However, it still
judged the US action to be illegal, ruling in favour of free
trade. WWF believes that the WTO is failing to fulfil the
mandate contained in the preamble to its own charter: to
promote trade that is environmentally responsible and that
encourages sustainable development.
Over-exploitation of eggs and adults
Under natural conditions, turtles suffer high hatchling, posthatchling and juvenile mortality, but those that survive the
early days grow into long-lived animals with delayed sexual
maturity and very low adult mortality. Unfortunately, conditions nowadays are far from “natural” and turtles suffer
mortality at all stages of their life cycle, leading to increasingly regular population crashes. In the days of Columbus, the
Caribbean Sea was described as being “thick with them [green
turtles], and they were of the very largest, so numerous that it
seemed that the ships would run aground”. This is a rare sight
today. The number of female leatherbacks nesting on the
Pacific beaches of Mexico has declined tenfold in less than a
decade; the number of nesting loggerheads in eastern Australia
17
THREATS AND ISSUES
has declined by 50 to 80 per cent since the mid-1970s;
Kemp’s ridley nearly went extinct. The list goes on, and makes
depressing reading. The causes are many and varied, but have
their roots in two basic characteristics of turtle biology which
render populations particularly vulnerable to the pressures
described above.
Turtle populations can be destroyed from the “bottom
up” by over-exploitation of the eggs, and destruction of
nesting sites. For example, as far as we know, green turtles
take 30 to 50 years to reach sexual maturity and remain
reproductive for about 20 years. Adults are the visible component of a turtle population; their numbers are maintained
by the gradual maturation of juvenile and sub-adult turtles.
This will continue to happen, even if no eggs are laid or
if all the eggs are collected. It will be many decades before
the number of adults begins to decline,
but over time the reservoir
of juveniles and subadults will become
progressively depleted until there are no more recruits.
These “last adults” will, in theory, survive for another 20
years during which time the situation may not seem too serious. In reality, however, the population is on the verge
of extinction because once these adults die there will be
no hatchlings, juveniles or sub-adults to replace them. If
juvenile and adults are being killed, e.g. as bycatch, then this
will simply happen more quickly.
International Agreements for Turtle Conservation
International trade in turtle products was formerly a major
cause of population depletion. Since all species of marine
turtles were listed on Appendix I of CITES, trade between
Party states has decreased. However, illegal trade
and hunting for international markets outside the
CITES framework remains of concern, and
local consumption continues.
Turtle and products for sale in Vietnam.
18
THREATS AND ISSUES
ELIZABETH KEMF
This group of species is ideally matched to the aims
expressed by the Convention on the Conservation of Migratory Species of Wild Animals (also known as the Bonn Convention or CMS). The text of the CMS includes many of the
concepts fundamental to regional conservation of migratory
marine animals and their habitats. With the exception of the
flatback (Natator depressus), all species of sea turtles are
listed in both Appendix I and Appendix II of the Bonn
Convention. The Inter-American Convention for the Protection and Conservation of Sea Turtles (IAC) is the only
major international treaty dedicated exclusively to sea
turtles and their habitats, formally setting standards for
their conservation.
The IAC recognizes that sea turtles
migrate and that they are resources
shared by the peoples of many nations.
Hence, the IAC has been vigorously
supported by many members of the
international community of sea turtle
biologists and conservationists, particularly specialists from Latin America. In
order to enter into force, eight countries
must ratify the agreement. Currently, 12
States have signed and six have ratified. The
treaty is expected to go into force in 2000.
The measures proposed in the IAC promote
regional management plans and accords. Its stated
objective is “to promote the protection, conservation and
Turtles and turtle products for sale in a hotel lobby in Ho Chi Minh City.
WWF/CATHERINE CHEUNG
recovery of sea turtle populations and of the habitats on
which they depend, based on the best available scientific
evidence, taking into account the environmental, socioeconomic and cultural characteristics of the Parties”. In
the same vein, the Protocol concerning Specially Protected
Areas and Wildlife (SPAW) to the Convention for the
Protection and Development of the Marine Environment
of the Wider Caribbean Region (known also as the Cartagena Convention) is complementary to the IAC. All six
species of Caribbean sea turtle are listed in Annex II of
the SPAW Protocol.
2000 WWF Species Status Report
19
WHAT WWF HAS DONE FOR MARINE TURTLES
WWF-CANON/MICHEL GUNTHER
hat
WWF has
done for
marine
turtles
Since it was founded in 1961, WWF has supported numerous
sea turtle conservation efforts worldwide. Much of the early
work involved mapping the distribution of nesting beaches,
with surveys in more than 40 countries. Other projects
focused on survival of eggs and hatchlings, establishment
of protected areas, research into sea turtle biology, ecology
and behaviour, monitoring the trade in turtle products,
investigating the threats from fisheries, and sponsoring
international conferences and workshops on sea turtle
conservation.
WWF assisted in the creation of what was to become the
IUCN/SSC Marine Turtle Specialist Group (MTSG). “The
present world situation for the great marine turtles is tragic,”
said a Statement issued after the First Working Meeting of
Marine Turtle Specialists organized by IUCN in 1969.
Describing 20th-century population declines as “catastrophic”, biologists called for a variety of conservation measures, more public awareness campaigns, and international
cooperation for turtle protection. WWF swung into action
immediately, funding surveys throughout the 1970s along
Loggerhead turtles have been a focus of WWF’s conservation work in the Mediterranean, especially in Greece and Turkey.
the coasts of southern Africa, Australia and Latin America.
In 1979, WWF supported the first World Conference on the
Conservation of Sea Turtles, and helped set in motion an
Action Plan of 137 urgent projects. For WWF 1980 was the
“Year of the Turtle”.
In the past 30 years, biologists have started to explore
the mysteries of turtle migrations by tagging adult and
immature turtles and more recently by using satellite technology. From these studies, it has become apparent that
20
WHAT WWF HAS DONE FOR MARINE TURTLES
WWF-CANON/MICHEL GUNTHER
regional approaches to turtle conservation are needed.
Because of the great mobility of these animals, vast numbers
of turtles are vulnerable throughout their ranges to a myriad
of threats, including intentional hunting/trapping and incidental capture in fishing nets. While WWF continues to support national efforts to conserve sea turtles, it is increasingly
focusing on regional approaches to conservation in the
Mediterranean, Indo-Pacific, eastern Pacific and Caribbean.
In 1999, WWF co-funded production of a state-of-the-art
publication, Research and Management Techniques for the
Conservation of Sea Turtles, prepared by the IUCN/SSC
Marine Turtle Specialist Group.
MEDITERRANEAN
Protecting nesting beaches
The major nesting areas for the Mediterranean’s green and
loggerhead turtles lie in the eastern part of the region, with
Greece, Turkey and Cyprus hosting the highest numbers.
The Mediterranean is thought to support the third largest
loggerhead nesting population in the world, after those of
Oman and the United States.
WWF and IUCN initiated nesting beach surveys in
Turkey in 1978 along the Aegean and Mediterranean coasts,
and started public awareness campaigns and a tagging programme. In 1987 the Turkish Society for the Protection of
Nature (DHKD), a WWF affiliate, launched a successful
campaign to stop a huge tourism development project for
the Dalyan/Koycegiz region, considered the Mediterranean’s most important loggerhead nesting area. Plans for
hotels were scrapped and Dalyan was declared a protected
area. In 1988, a survey of the entire Turkish Mediterranean
coast identified 17 important turtle beaches. These beaches
faced a number of threats: of the 606 km of beaches, 40 per
cent were severely impacted by tourism. Moreover, about
half of the beach areas used by nesting turtles had been
destroyed by sand extraction. DHKD initiated a number of
conservation actions at these sites and lobbied the government to reinforce existing conservation regulations and
establish new protected areas. Thanks to these efforts,
marine turtles have become a symbol of the conservation
movement in Turkey.
The nesting density of loggerheads on Zakynthos
Island, Greece, is among the highest in the world, partly
because red foxes (Vulpes vulpes) do not occur, so predation
pressure is low. The core area for turtles on Zakynthos is
Sekania beach, on the southern coast of the island, where
nesting turtles reach a density of 3,000/km2. In 1981, WWF
assisted Greek conservationists to map the beaches and start
long-term monitoring of the Zakynthos turtles. Initially,
turtle conservation met with hostility, because it was seen
to be against development interests. However, thanks to
a public awareness project started in 1986 by the Sea
2000 WWF Species Status Report
Tourists on a turtle nesting beach in Zakynthos, Greece. In December 1999
the area was declared a national park by the Greek government.
Turtle Protection Society of Greece (STPS), the turtles of
Zakynthos are now major tourist attractions. STPS is continuing to implement turtle monitoring, tourist awareness
and school education activities with WWF support.
Until the late 1980s, little research had been carried out
on marine turtles along the North African coast, although it
was known that the extensive sea-grass beds in the Gulf of
Cabes constituted a major foraging area for green turtles.
Around 3,000 were being killed annually in the Gulf of
Cabes, with up to 6,000 killed in Tunisia as a whole. From
1989 to 1993, WWF supported a study to identify major
breeding, feeding and overwintering areas for turtles along
the North African coast and to discover the extent of turtle
mortality. The study concentrated on the Tunisian coast,
although areas in Morocco and Algeria were also surveyed.
Further survey teams along Libya’s coastline between
1995 and 1998 discovered unknown and significant loggerhead nesting beaches, especially along the northeastern
coast. These “extra” turtles could explain the fact that
Egyptian fisheries, which have been responsible for killing
large numbers of adults for many years, have not exhausted
stocks of Mediterranean turtles long before now.
Threats from fisheries
In 1977, WWF started to identify threats to adult and young
turtles in the western and central Mediterranean and devise
strategies to protect them. A survey of fishermen at Spanish
ports found that the most pressing danger from coastal
fisheries was accidental bycatch. A later study estimated
that perhaps 16,000 turtles, mainly loggerheads, were killed
each year by commercial swordfish longline fisheries.
Although turtles are released after capture, many drown.
If released alive, most have hooks in their mouths. Between
1987 and 1990, WWF funded a major study to determine
the impact of longline fishing, and the survival rates of
hooked turtles.
21
WHAT WWF HAS DONE FOR MARINE TURTLES
In 1994, WWF initiated a strategy to conserve turtles,
especially loggerheads, throughout the Mediterranean. A
main objective of this strategy is to prevent mortality of adult
turtles at sea. Research undertaken by biologist Dr Luc
Laurent combined field observations with studies of turtle
genetics and population dynamics. His final report, Conservation and Management of Mediterranean Loggerhead
Sea Turtle (Caretta caretta) Populations, was published in
1997. Laurent’s surveys identified a number of significant
threats to the loggerhead: thousands being killed each year
by Egyptian fisheries, followed to a lesser extent by fleets
from Turkey, Tunisia, Libya and Italy. He estimated that
more than 20,000 turtles were being captured as bycatch by
Spanish longline fisheries, with about 4,000 of these dying as
a result. Significant numbers were also being killed by bottom trawls operated by Turkish, Greek and Egyptian fleets.
In Egypt, sea turtle meat is still traded for human consumption, and turtle blood is occasionally drunk as a traditional
medicine for anaemia. Green turtles, highly endangered
in the Mediterranean, comprise one in every three turtles
slaughtered in Egypt.
INDO-PACIFIC
Australia -Malaysia -Indonesia -Oceania
In the 1960s and 1970s, WWF funded turtle surveys in
Australia, Thailand, Malaysia and western Indonesia.
Dr Robert Bustard of the Australian National University
undertook surveys of the Queensland coastline and offshore
islands. He discovered several flatback “rookeries” (nesting
beaches) situated safely in uninhabited Aboriginal reserves.
He also confirmed the first recorded breeding of hawksbills
in Australia, in Long Islands in the Torres Strait. As a result
of these surveys, new national parks to protect key nesting
beaches were approved by the Queensland government.
By the 1970s, the situation in Thailand was also very
worrying. Turtle eggs were being collected on a commercial
basis, the harvest was in steep decline, and regulations to
limit the harvest were largely being ignored. Even more
threatening was the increase in the number of drift-net vessels that were killing large numbers of adults. In 1980, WWF
provided boats to the Thai National Park Division to combat nest poachers and undertake a status survey of turtles in
the Tarutao National Park, composed of some 50 islands off
the southwest coast of Thailand. In 1987 WWF funded protection of nesting turtles in southern Thailand. From 1990 to
1996 WWF assisted villagers in Phuket and Phang Nga
Province to become “model self-sufficient sea turtle conservation villages”. However, tourism or egg collection and
accidental drownings of sea turtles in nets continue to challenge
the survival of marine turtles in Thailand’s coastal waters.
22
WWF/CNRS Leatherback nesting camp in French Guyana.
In Malaysia, WWF assisted the Fisheries Department to
protect leatherbacks on the Terengganu coast in Peninsular
Malaysia. Terengganu is the only place in western Malaysia
where leatherbacks nest, and was in the 1970s probably the
second largest leatherback rookery in the world after the
one in French Guyana. Back then concerns were growing,
however, over adult mortality as Terengganu leatherbacks
had been caught by fishermen as far away as the Philippines
and Japan. In 1977, recommendations were made to the
Malaysian government for a marine national park and
reserve which would protect important nesting beaches on
Pulau Redang, an island off the Terengganu coast, and surrounding islets. Consumption and sale of leatherback eggs
were banned in 1988.
In 1989, WWF provided funds for an advisor to assist
the Malaysian Federal Department of Fisheries to coordinate marine turtle conservation. The advisor, Dr Jeanne
Mortimer, conducted surveys of habitats critical for marine
turtles in Peninsular Malaysia, Sabah and Sarawak; ran
training courses for the establishment and management
of a leatherback sanctuary at Terengganu and a number of
hatcheries; and investigated causes of sea turtle mortality.
Despite government and WWF efforts, the nesting
leatherbacks of Terengganu have practically disappeared.
The olive ridley population has suffered serious declines in
WHAT WWF HAS DONE FOR MARINE TURTLES
to establish a network of protected areas in Irian Jaya. WWF
has also been involved in turtle protection activities in the
Teluk Cenderawasiih National Park.
WWF/HERVÉ LETHIER/RAMSAR
Solomon Islands
the past 10 years in Terengganu, while the remaining nesting
population of hawksbill is also very low, according to
the Sea Turtle Research Unit of the University of Putra
Malaysia, Terengganu.
In the 1960s, the turtle egg harvest had declined in
Indonesia (at least in Java). The MTSG voiced grave concern over the extent of hawksbill carapace exports to Japan.
Some 76,636kg were exported from Indonesia in the period
1966 to 1972. This is the equivalent of 150,000 adults. There
was also significant trade in stuffed turtles, turtle oil, meat
and leather. The increasing pressure from fisheries undoubtedly constituted the greatest threat to marine turtles in the
whole Indo-Pacific region, except in Australian waters
where they were protected by law.
In 1979, WWF funded a survey of the remote Aru
Islands, south of Irian Jaya, Indonesia, where leatherbacks
are hunted by some communities for subsistence, and green
turtle meat and eggs are also eaten. However, there was also
commercial exploitation of hawksbills for their shells and
populations had declined. A 100,000 ha marine reserve in
the southeastern part of the islands was proposed. In 1984, a
turtle trade study was conducted on Bali, Ujung Pandang,
Surabaya and Jepara.
WWF identified a number of important sea turtle nesting beaches at Jamursba-Medi as part of a larger programme
2000 WWF Species Status Report
Many years ago, clashes between hunting parties seeking
turtles around the remote Arnavon archipelago were so
fierce, and loss of life so high, that legends developed of
beaches haunted by ghosts. By the 1970s, Arnavon still had
the greatest aggregations of hawksbills in the South Pacific,
but they were under threat because of the increased accessibility offered by outboard motors. From 1979 to 1981, WWF
undertook a turtle status survey in order to plan for the sustainable utilization of this traditional resource. The first priorities were to strengthen protection of the Arnavon turtle
sanctuary (which was set up in the 1930s), to train local wardens, and to achieve a higher hatching success. The project
report recommended that, on the one hand, traditional
subsistence use should be continued, with permits for
leatherbacks and curbs on trade in meat from other species.
Commercial exploitation on the other hand, should be controlled, with a total ban on tortoiseshell exports.
Philippines
In 1993, WWF funded the ASEAN Regional Symposium on
Marine Turtle Conservation, bringing together experts from
throughout the Asia Pacific region to develop a Regional
Sea Turtle Conservation Programme. Among the recommendations was the establishment of transboundary protected areas to protect turtle populations. Areas proposed
included the Philippine-Sabah Turtle Islands, Sipadan
Islands, and the Berau Islands which support the largest
breeding aggregation of green turtles in the region. WWF
participated in a meeting between representatives from the
Philippines, Malaysia and Indonesia, and collaborated on a
conservation strategy for the island groups mentioned
above. The Turtle Islands Heritage Protected Areas was
declared in 1996. (See p. 30)
INDIAN OCEAN
Between 1969 and 1974, WWF supported extensive surveys
in the southwest Indian Ocean. As a result of these surveys,
five new Marine Reserves were created: Paradise Islands,
Mozambique, and four islands belonging to Reunion.
Observations were also used to propose four additional
protected areas. WWF has also supported conservation of
turtles along the Tongaland coast (now Kwa Zulu Natal)
for some 30 years. (See p. 32)
Elsewhere in the Indian Ocean, WWF has funded surveys of nesting beaches on mainland India and its offshore
islands in the Andamans and the Nicobars. WWF has also
23
WHAT WWF HAS DONE FOR MARINE TURTLES
helped protect nesting beaches in Pakistan and has been
active on Cousin Island and the Aldabra Atoll in the
Seychelles. In the 1980s, WWF funded a field study of
hawksbill and green turtles in the Seychelles, leading to
the government of Seychelles introducing a number of
conservation measures.
A survey of Oman’s turtle beaches, started in 1977,
revealed that Masirah Island, off the southern coast, held
more than 30,000 loggerheads (the largest loggerhead rookery in the world). The principal threats to loggerheads on
Masirah were flooding of nests, and lights near the beach
that distracted and disoriented the hatchlings. The shallow
waters of the Masirah Channel and Sawqirah Bay were
major green turtle feeding grounds, and large green turtle
rookeries were sited at Ras al Hadd and Masirah. Masirah’s
green turtles, which had provided eggs and meat for generations of the island’s people, were in severe decline and the
government of Oman was concerned that they be adequately
protected. Data collected by local people helped define turtle nesting seasons, local harvest rates and turtle populations.
India – Home of World’s Largest
Olive Ridley Rookery
For years, the occurrence of the olive ridley turtle along India’s
Gahirmatha coast was known to the local inhabitants of the Kanika
Raj area, who paid andakar (egg tax) on the boatloads of eggs they
collected during the nesting season. News of the existence of the Bhitarkanika rookery was first brought to the scientific world and made
public by Dr HR Bustard, then an FAO consultant, who visited the
area in the early 1970s. He estimated that a large breeding population
of olive ridleys migrate to the northern Orissa coast to nest, and urged
the government to protect the sea turtles and their nesting grounds.
According to Dr Bustard about one million (male and female
in equal ratio) olive ridleys visited the Gahirmatha to lay about
50,000,000 eggs every year. In 1975 the government declared the
Bhitarkanika Wildlife Sanctuary (BWS), thus giving protection to the
important turtle rookery and the mangrove forests. But over the years,
the Orissa mangroves, the second largest mangrove ecosystem in
India, has become increasingly imperilled by prawn aquaculture.
More than 30 km2 of the total 115.5 km2 of Bhitarkanika mangrove
forests have already been razed and the rest is threatened with ending
up as one of the 6,500, or more, prawn ponds already covering over
20,000ha of coastal Orissa.
In 1994, concerned over the threats to the marine turtles and the
mangrove forests, WWF-India filed a petition in the Orissa High
Court. The Bhitarkanika Sanctuary Case contended:
1. to restrain the State of Orissa from constructing jetties, fishing com-
WWF-CANON/MAURI RAUTKARI
plex, roads and bridges etc. within and around the Bhitarkanika
Wildlife Sanctuary,
2. to direct the State to provide infrastructure, personnel etc. and to
protect and conserve the mangrove forest and the endangered species
of wildlife of the Sanctuary and its surrounding areas,
3. to appoint a committee to carry out an Environmental Impact
Assessment in and around the Sanctuary.
Green turtle rescue operation in Pakistan near Karachi.
The Orissa High Court gave its judgement on 14 May 1998 and the
Court directed, inter alia, that:
In 1995, WWF drafted a Western Indian Ocean Marine
Turtle Conservation Strategy so that national and international organizations working in the region could link
their activities to the IUCN/SSC Global Action Plan for
Marine Turtles.
1. no trawlers should enter the Gahirmatha area,
2. immediate steps should be taken to evict the unauthorised occupants of forest land within the boundary of the BWS,
3. all forest land including rivers and creeks within the boundary of
the BWS should be declared as reserve forest and treated as a property of the Forest Department,
CENTRAL AMERICAN REGION
Caribbean and Western Atlantic
WWF’s work in Suriname started in 1967 and continues
today. Surveys of beaches in Suriname and French Guyana
in the 1970s by turtle biologist Peter Pritchard, Director of
the Chelonian Research Institute, confirmed the region to be
the world’s most important breeding area for leatherbacks.
24
Suriname’s Foundation for Nature Preservation
(STINASU) approached WWF to support research into
the distinct green turtle population feeding in waters off
Brazil and breeding in Suriname. In 1980, “Operation Headstart” was launched. Brazil’s Projeto Tartaruga Marinha
(TAMAR) was started by the Institute for Forestry Development (IBDF) in 1980 and executed by local conservation
S. BHASKAR
WHAT WWF HAS DONE FOR MARINE TURTLES
Researcher observes nesting turtle’s return to sea.
4. no new lease of forest land or water bodies should be granted
within the Sanctuary,
5. aquaculture farms should not be allowed within the Sanctuary
boundary,
6. appropriate use of natural resources should be made for improving
the quality of life of the people living in and around the Sanctuary,
7. all trawlers operating in the area shall be required to use Turtle
Excluder Devices (TEDs).
The High Court has specifically asked the state government to
set up a High Level Committee for protection, conservation and
research on sea turtles. In 1997, the Orissa Government declared the
relevant area as the Gahirmatha (Marine) Wildlife Sanctuary. This
notification declared certain activities to be unlawful under the
Wildlife (Protection) Act, 1972. In sum, the judgment of the Orissa
declared as protected areas. The project became a model for
a well-rounded conservation effort protecting all stages of
the turtles’ life-cycles, and incorporating local involvement,
public outreach and education.
Elsewhere in the Caribbean, WWF funded surveys of
Kemp’s ridley turtles in Mexico, and the only known
major green turtle rookery in the eastern Caribbean on
Aves Island, Venezuela, which is now a sanctuary. WWF
continues to be involved in turtle conservation efforts in this
region. WWF also provided funds to strengthen protection of nesting green turtles in the Tortuguero National
Park, Costa Rica, the largest green turtle rookery in the
western Caribbean.
By the early 1980s hawksbill turtles, clearly in trouble
worldwide, were almost extinct in the Caribbean. Little was
known of their ecology or movements in the wild. WWF
funded veteran turtle biologist Dr Archie Carr and his colleague Anne Meylan to undertake research into hawskbill
ecology in Panama and the Leeward and Windward Islands
where major coral reef feeding areas are found. Dr Carr also
set out to solve “the riddle of the missing turtles” (the mystery of where hatchlings disappear to from the time they
enter the sea until they turn up as adolescents a year or so
later). He wanted to test a theory that hatchlings spend the
first year of life floating and feeding in the rafts of sargassum
weed drifting in the currents in the western Caribbean. He
tagged more than 2,000 hatchlings at Tortuguero in Costa
Rica, examined stomach contents of young loggerheads
washed ashore after storms, and conducted interviews with
fishermen. All evidence suggested that loggerheads from
breeding colonies in eastern Florida, and green turtles
hatched on Caribbean beaches, indeed spent much of their
first year in the sargassum mats.
High Court has, except for permitting part of the proposed road in the
BWS, not allowed any other developmental activity in the Sanctuary.
This road is also to be diverted to minimise any adverse impact.
In 1999, the West Bengal Forest Department reported 13,000
olive ridleys were killed in Orissa by fishing trawlers.
By Dr S M Satheesan, WWF-India
NGOs and government agencies. In 1986, WWF began
assisting these bodies to implement measures for curbing
poaching and increasing public awareness about the plight
of turtles. An innovative approach was to hire former turtle
egg poachers to become beach wardens. By 1992, about
1,000km of nesting beaches were policed by project personnel and four of the ten most important beaches had been
2000 WWF Species Status Report
Eastern Pacific
In 1970, with WWF support, Peter Pritchard visited the
Galapagos Islands (Ecuador) to determine the status of the
East Pacific green turtle (sometimes called black turtles,
Chelonia mydas agassizi) and their rookeries. He found that
while they were generally undisturbed by humans, their
nests at the important rookery in James Bay, Santiago
Islands, were threatened by predatory feral pigs. To ensure
the continued survival of both black turtles and the famous
giant land tortoises, WWF subsequently assisted with control of feral pigs on Santiago and with a long-term green turtle monitoring programme implemented by scientists from
the Charles Darwin Research Station.
In the early 1970s there were worrying reports of large
catches of turtles by foreign fishing fleets operating in
Galapagos waters. This problem would assume much larger
proportions in the coming years and threaten not only sea
turtles but also a number of other species including sharks
25
WHAT WWF HAS DONE FOR MARINE TURTLES
and seals. In 1971, a Japanese refrigerator ship purchased
a capacity load of fish and turtles from local fishermen, an
activity subsequently banned by the Ecuadorian government.
The mass slaughter of olive ridleys for their leather
started in the 1960s. During the 1970s, an estimated 450,000
turtles, mainly Pacific olive ridleys, were slaughtered in
Ecuadorian waters to supply the international trade. Most
exports (clearly in contravention of CITES) were to the
United States, but some were to European countries, mainly
France and Italy. Although Ecuador officially closed the
turtle fishery in 1981, it subsequently came to light that clandestine turtle fisheries and processing plants were operating.
In 1989, WWF assisted Ecuador’s Fundación Natura to
make an undercover investigation of these operations.
Despite setbacks, the conservation effort on the Michoacan
beaches started to bear fruit by the early 1980s. Poaching
was reduced, children were recruited to protect nests, and
a number of Mexican biologists joined the team. By 1990,
WWF’s efforts to protect Mexico’s turtles had become a
multifaceted conservation endeavour which included public
The battle for Mexico’s sea turtles
In 1967, WWF supported work in the Pacific coast of Honduras and Mexico to assess the status of marine turtles.
Although still fairly abundant (on one “protected” beach in
San Luis de la Loma, Guerrero, an estimated 30,000 olive
ridleys were observed in a single arribada), commercial
exploitation of nests and adults was rife, and even prominent
local officials were flouting the law.
Monitoring in Mexico continued through the 1970s. By
1977, olive ridleys were in serious decline, but the harvest
was still in full swing. WWF reported “70,000 ridleys, 98 per
cent of them gravid (pregnant) females were harvested this
year from a population estimated at 150,000 animals”.
Poaching and disturbance of nesting beaches of all turtle
species left “little doubt that we will soon be without
Mexican populations of Pacific, green, olive ridley and
leatherback turtles. The hawksbill is already depleted… The
Mexican people have been taking 500,000 to a million sea
turtles per year since the early 1960s. This represents 70 per
cent of the world harvest”.
The East Pacific green (or black) turtle was also in serious trouble. In the early 20th century more than 10,000
females per night had nested in Michoacan state, but a mass
slaughter in the early 1970s by leather hunters resulted in
their almost total disappearance by 1977. Despite this, the
Mexican government had granted a licence to a private turtle fishery to expand its operations in waters off two of the
only three known nesting beaches of this species.
In 1978, in the face of official Mexican government
policy to increase exploitation of its marine turtles, WWF
biologist Richard Felger and his colleagues developed a
comprehensive plan for the protection and management of
all sea turtle species in Mexico. This was also the start of a
long-term WWF project to save the turtles of Michoacan
with the cooperation of the Mexican Fisheries Department,
the Mexican Navy, and students and faculty of the University of Michoacan.
26
Patrolling the beach as part of the TAMAR project in Brazil.
awareness, university training, protected area establishment
and management, research and species protection. The
project also served as a model for multi-institutional cooperation for marine turtle conservation.
Honduras
In 1987, WWF supported a study of the status of Pacific olive
ridleys in the Gulf of Fonseca, Honduras. Seven local communities depended on income from turtle eggs, and the situation had not improved since Pritchard reported two
decades earlier that there were more hueveros (egg collectors) than turtles on the beach. Education programmes were
WHAT WWF HAS DONE FOR MARINE TURTLES
started to prevent over-exploitation of the resource. In 1989,
WWF gave funds to assist government efforts to conserve
the Punta Raton population of turtles in the Gulf of Fonseca.
The Gulf of Fonseca is the focus for the ongoing Central
American Environment Programme (Programa Ambiental
Centroamericano – PROARCA).
ment Programme at the National University of Costa Rica.
This involved training ecologists in turtle research and
management techniques.
In 1985, WWF co-sponsored the first Symposium on the
Marine Turtles of the American Pacific and, in association
with the University of Costa Rica, initiated funding of an
international programme to monitor sea turtle movements
on Latin America’s Pacific coast.
Eastern Atlantic
WWF/ARQUIVO PROJECTO TAMAR
With help from WWF, Senegal established a number of
marine protected areas in the 1970s, including Iles de la
Madeleine, Langue de Barbarie and Delta du Saloume
National Parks. In 1980 and 1981 WWF gave funding to the
Marine Biological Department of Senegal to carry out basic
research and to discover if any coastal areas important for
turtles were not yet protected. Beaches were being threatened by development and turtle fishing had become commercialized with meat being sold in urban centres. WWF
also provided equipment for turtle protection to the Delta
du Saloume and Kalissaye ornithological reserve.
Costa Rica
In 1982 WWF joined a research and monitoring project at
Nancite Beach in the Santa Rosa National Park which hosts
one of the greatest olive ridley arribadas in the world. Adult
turtles from this population were vulnerable to heavy fishing pressure when they moved north to Mexico and south to
Ecuadorian waters to feed, but were protected while nesting
at Santa Rosa, which provided excellent conditions for
research into their life cycles and movements. In 1990, WWF
joined a National Science Foundation study of the factors
that trigger the great arribadas at Nancite, and the area
became the focus of a WWF-supported Wildlife Manage-
2000 WWF Species Status Report
27
WHAT WWF IS DOING FOR MARINE TURTLES
hat
WWF is
doing
for marine
turtles
Monitoring a turtle beach in the Mediterranean.
MEDITERRANEAN
In 1998, WWF published recommendations1 for a new
approach to conserving the Mediterranean’s turtles, based
on Luc Laurent’s wide-ranging study of their ecology.2 This
approach sets out a number of urgent measures to reduce
mortality of adult and sub-adult turtles, including: reduction
of deliberate killing, especially in Egypt; reduction of
bycatch in bottom trawls (especially in the eastern part of the
Mediterranean), longline fisheries and a variety of small
coastal fisheries; and education aimed at reducing mortality of turtles accidentally caught by all kinds of fisheries.
Efforts to protect nesting beaches in Greece, Turkey and
Cyprus, to limit damage by urban and tourist developments
and to reduce predation by dogs and foxes need to continue.
WWF is working to establish a fully representative
network of protected areas, as part of its “Out of the Blue”
programme for the conservation of the Mediterranean. The
present number of marine and coastal reserves and national
parks is grossly inadequate, and management of the few that
do exist is often poor or totally lacking. Scientists have been
28
WHAT WWF IS DOING FOR MARINE TURTLES
Zakynthos. In doing so, the immediate threat from tourist
disturbance has been reduced. A study commissioned by
WWF has led to steps being taken to address other threats
to the site such as erosion, sedimentation and vegetation
encroachment. Local people have been employed as
wardens on the beach during the nesting season, and a
programme of raising public awareness about turtles has
been started. Sekania beach is part of a Marine National
Park in Zakynthos, declared by the Greek government in
1999. Shortly before the government announcement, the
European Commission made an application to the European Court of Justice citing Greece’s failure to fully protect
its loggerhead turtles in accordance with the EU Habitat’s
Directive. The Sea Turtle Protection Society, WWF and
Greenpeace are all working to conserve the nesting sites.
Turkey
WWF-CANON/MICHEL GUNTHER
WWF’s “Out of the Blue” programme is continuing efforts
to conserve Turkey’s turtle beaches in collaboration with
DHKD and the Turkish Sea Turtle Committee. Current
work is based on a recent report on sea turtle status.3 Within
a framework of integrated coastal zone management, the
carrying out a “gap analysis” to ensure critical habitats
of threatened species such as monk seals (Monachus
monachus), marine turtles, and certain fish, are protected,
particularly outside European Union states. They have paid
special attention to the opportunities for Integrated Coastal
Zone Management, in an effort to ensure that nature
conservation and sustainable development move forward
together. One of the most important priorities is to initiate
protection of the newly-discovered turtle beaches in North
Africa, particularly those in Libya, as well as the sea-grass
beds that support turtles in shallow coastal waters.
WWF has started to place observers on Italian longline
fishing fleets to monitor fish catches and document the
extent of sea turtle and shark bycatch and mortality.
Greece
In the early 1990s, tourism development threatened to overwhelm efforts to protect nesting turtles in Laganas Bay.
WWF purchased the area surrounding Sekania beach,
which has the highest nesting density of loggerheads in
the Mediterranean and hosts more than half the nests in
2000 WWF Species Status Report
29
WHAT WWF IS DOING FOR MARINE TURTLES
programme includes raising public and local government
awareness, enhancing local expertise on turtles, and developing methods of monitoring nesting populations.
INDO-PACIFIC
In 1999, WWF, together with a network of NGOs and
governments, participated in the second Association of
Southeast Asian Nations (ASEAN) sea turtle meeting,
15 to 17 July in Sabah, Malaysia. Coordinating measures for
marine turtle protection on a regional basis is a priority for
marine turtle conservationists. The region’s marine turtles
and other species are threatened by coastal development,
sand and coral reef mining, pollution, unsustainable egg
collection, and entanglement in fishing nets or accidental
killing by long-line fisheries. In Malaysia alone, four species
of marine turtles have fallen dramatically in recent decades
with leatherbacks in critical danger. Despite government
and WWF efforts over the past 30 years sea turtles are in a
state of decline not only in Malaysia but also throughout the
region. The creation in 1996 of the Turtle Islands Heritage
Protected Area, a group of nine islands shared by the
Philippines and Malaysia offers some hope for the future.
Indonesia
In 1991, Indonesia’s Directorate General for Forest Protection and Nature Conservation (PHPA) asked WWF to help
strengthen its marine conservation programme. Measures to
protect marine turtles are urgently needed; recent surveys
have shown that at least 20,000 adult and juvenile green
turtles are killed annually, even in marine reserves, to supply the Bali meat market. Other threats include the annual
harvesting of up to nine million turtle eggs of all six species,
ill-planned tourist developments, and the destruction of seagrass “pastures” used by green turtles. WWF has launched
a Regional Sea Turtle Conservation Project to lobby for
stricter laws, enforcement of trade regulations and coordination of conservation efforts throughout the country.
The Marine Reserve of Aru Tenggara, established in
1991, is a focus for WWF-funded research on the ecology of
green and hawksbill turtles. Despite its protected status, the
Aru Reserve’s marine resources, including turtles and their
eggs, are exploited commercially in large quantities. Data
from these studies will underpin conservation efforts and
help formulate a sound management plan for the reserve,
including measures allowing for a more sustainable harvest
of turtles by local communities.
Unplanned development in the tourist paradise of Bali
threatens disaster for its precious marine biodiversity, which
is also a key attraction for visitors. WWF is supporting
efforts to introduce responsible ecotourism and to protect
the last nesting beaches of olive ridleys and hawksbills in the
northwest of the island. Although the Bali government has
30
Terengannu, Malaysia. Despite WWF and government efforts, 98 per cent
of leatherback nests have been lost in the past 40 years.
announced measures to limit the numbers of green turtles
imported to the island from throughout the region, quotas
are largely ignored. The government of Indonesia needs to
improve enforcement. (See p. 37)
Philippines
Since 1993, WWF has been encouraging ASEAN countries
to seek ways of coordinating the management of their
marine turtles. A major achievement was the establishment
in 1996 of the Turtle Islands Heritage Protected Area, the
world’s first transboundary protected area for marine turtles.
Seventy per cent of the Turtle Islanders live below
the poverty line and health and welfare facilities are basic
or totally lacking. Fishing and turtle egg collecting are
traditional (and very important) sources of income. In fact,
highly nutritious turtle eggs are usually sold rather than
eaten, even though many of the islands’ people are malnourished. WWF’s wide-ranging programme for the Turtle
Islands has several goals: to help raise health and living standards; to ensure that use of marine resources is sustainable;
and to educate islanders about the significance of their new
WWF/WWF MALAYSIA/MALAYSIA PHOTO SERVICE
WHAT WWF IS DOING FOR MARINE TURTLES
and unique protected area. In order to ease the pressure on
turtle eggs and other resources, innovative ways of making
a living are urgently needed. Guidelines for ecotourism to
the islands have been drawn up and economic opportunities
for the islands’ women are being explored, as well as ways to
involve them fully in the conservation effort.
Turtle research is also being undertaken and the results
will be incorporated into a management plan that is being
developed for the islands. A database is being set up
for Baguan Island, which has the highest nesting density
of any of the Turtle Islands, to assist scientists to monitor
short- and long-term turtle population changes and cycles.
A few turtles have been fitted with radio transmitters
and their movements tracked by satellite. (See website:
www.oneocean.org/ambassadors)
Malaysia
As a result of pressure from coastal development, sand mining, pollution, collection and consumption of eggs, and
entanglement in fishing nets, numbers of nesting marine turtles (of four species) in Malaysia have fallen drastically in
2000 WWF Species Status Report
recent decades, with leatherback nests declining by 98 per
cent since the 1950s. The most important remaining turtle
beaches are in the states of Terengganu (east coast of peninsular Malaysia), Sabah and Sarawak.
In response to this situation, a national seminar on the
conservation management of marine turtles (and terrapins)
was organized in October 1996 by the Fisheries Department
of Malaysia, in conjunction with WWF, other NGOs,
research institutions and corporate partners. Following up
on the seven resolutions arising from the seminar, WWF is
working together with the Fisheries Department to formulate model legislation for the protection of turtle nesting and
feeding sites, together with guidelines for hatchery management. It is hoped that individual states will enact legislation
based on this model: currently there is wide variation
between states. WWF is leading calls for a nation-wide ban
on the collection, sale and consumption of turtle eggs, whilst
the Fisheries Department is experimenting with TEDs,
to try to reduce the number of net deaths.
In May 1999, WWF-Malaysia published the fourth
handbook in its Integrated Coastal and Estuarine Area
Management series, dealing specifically with marine turtles
(and terrapins) and aimed at planners and decision-makers.
One month later saw the opening of the Ma’Daerah Turtle
Sanctuary at Kertih, in Terengganu. WWF managed the
process of establishing this important educational and public awareness facility, with funding provided by a subsidiary
of BP Amoco Malaysia.
Vietnam
At present, no legal limits are imposed in Vietnam on the
use of marine resources, including turtle eggs and meat.
Populations of leatherback, loggerhead, green and hawksbill turtles are in serious decline. With WWF’s help, the government is identifying suitable areas along the Vietnamese
coastline for establishment of a network of marine protected
areas. An existing coastal reserve is the Con Dao National
Park in southeastern Vietnam, one of the most important
sea turtle nesting areas in Southeast Asia. WWF and park
staff are continuing a research and monitoring programme
on marine turtles, started four years ago, as part of a wider
plan to improve management of Con Dao. There are plans
to involve more local people, especially fishermen, in the
effort to conserve marine turtles within this archipelago of
16 islands.
WESTERN INDIAN OCEAN
In November 1995, WWF co-sponsored an MTSG-IUCN
regional meeting in the Western Indian Ocean to identify
priority activities for marine turtle conservation. WWF is following up on the recommendations of the MTSG’s Marine
Turtle Conservation Strategy and Action Plan for the West-
31
WHAT WWF IS DOING FOR MARINE TURTLES
schools. The remoteness, lack of infrastructure and relative
insecurity of this area near the Somali border make this a
challenging task, but there has been an enthusiastic response
from several of the local communities. WWF encourages
implementation of the Sea Turtle Recovery Action Plan for
Kenya, published by the Kenyan Sea Turtle Conservation
Committee and the Kipini Community Conservation and
Development Programme.
WWF/RICK WEYERHAUSER
Madagascar
Hawksbill turtle from waters off Bazaruto Island, Mozambique.
ern Indian Ocean and working to strengthen the network of
turtle biologists in the region. Since 1996, WWF has sponsored regional scientists in attending international marine
turtle meetings and in 1997 co-sponsored a workshop on
TED technology for resource managers and fishermen from
Kenya, Tanzania, Eritrea, Madagascar and Mozambique.
WWF is involved in a number of marine protected areas
on the east coast of Africa, including Mafia Island in Tanzania, the Kiunga Reserve in Kenya, and the Bazaruto Archipelago in Mozambique. A prime objective in all these areas
is to ensure that marine resources are used sustainably by
local communities and that critical habitats for coral fish,
marine turtles, and dugongs are protected.
WWF-India has also funded a project titled “Status,
ecology and management of olive ridley sea turtles and their
nesting habitats along north coastal Andhra Pradesh”
through its Conservation Corps Volunteer Programme of
CCV Division and Protected Area Programme of Forest &
Wildlife Division. The project was executed from January
1997 to June 1998.
The southern coast of Madagascar has great potential for
ecotourism based on its landscapes and wildlife, including
marine turtles. Community-based conservation programmes
are being started up in the Fort Dauphin area, where green,
hawksbill and loggerhead turtles come ashore to nest.
The area has been identified by the Malagasy government
as a priority area for tourism development.
Southern Africa
WWF-South Africa is continuing to support the government
of South Africa’s Tongaland Sea Turtle Project based on
the northern coast of KwaZulu-Natal Province. This study,
which includes southern Mozambique and the Comores, has
been going for more than 30 years and is providing valuable
data on long-term trends in loggerhead and leatherback
nesting populations, and migratory movements of turtles. In
South Africa, the main focus is on a 56 km stretch of beach
north and south of Bhanga Nek, which is regularly patrolled
by field rangers and students. Since 1997, several tagged
females have been tracked by satellite. The wanderings of
one female leatherback were of epic proportions; she was
recorded swimming south past the southern tip of Africa
into the Atlantic, then headed east towards Australia,
covering 7,000 km in five months before the transmitter
battery failed.
WWF is working in partnership with the Kenya Wildlife
Service and other organisations on a wide-ranging conservation and development project for the relatively new
Kiunga Marine Reserve on Kenya’s northern coast, and the
villages that occur within its boundaries. Turtle nesting
beaches are regularly surveyed. For example, local people
contributed almost 100 reports in 1998, and there is a lively
programme of conservation education in the local primary
32
WWF/DENIS HUOT/BIOS
Kenya
Hawksbill turtle swimming offshore in the Bahamas.
WHAT WWF IS DOING FOR MARINE TURTLES
LATIN AMERICA AND THE CARIBBEAN
CENTRAL AMERICAN REGION
Annually, more than 80,000 turtles, mainly greens and
hawksbills, are still captured off the coasts of Central
America. Among the direct measures urgently needed are
the prevention of accidental capture of olive ridleys by
shrimp fishermen, (throughout the region), and of leather-
WWF/F DI DOMENICO/PANDA PHOTO
Marine turtles are a “species of special concern” or flagship group for WWF’s Latin America and Caribbean
Programme. In late 1999, WWF sponsored, together
with IUCN/SSC Marine Turtle Specialist Group, WIDECAST and UNEP, a regional meeting in the Caribbean
to promote a discussion on the need for regional management of marine turtles. The meeting was attended by
31 resource managers from 27 governments who represented 35 of the countries and territories of the Wider
Caribbean. Recommendations of the meeting included
the need to: strengthen collaboration among stakeholders;
promote greater community participation; support
scientific research and monitoring of turtles and their
habitats; develop regional and national management
plans; improve implementation of national laws; and
Leading scientists at the meeting presented clear evidence
that the populations of all six species in the Caribbean are
severely depleted and endangered. It became obvious that no
population has a chance of recovery unless major changes to
the patterns of use occur and there is regional management
among range states. The only exception to this is the Kemp’s
ridley. While it remains a fraction of its original population, it
is recovering after decades of conservation effort by its range
states, the United States and Mexico. (See next page.)
WWF is working with TRAFFIC to monitor and stop the illicit trade in hawksbill turtles like the one pictured here.
harmonize national policies for sea turtle conservation
throughout the Wider Caribbean. National resource
managers identified the elements of effective scientific
management. What also emerged was a consensus with two
key elements:
1. the understanding that marine turtles have traditionally been a consumptive resource in the Caribbean; and,
2. true management can only occur through regional
coordination among range states.
2000 WWF Species Status Report
backs and other species by longline fishing fleets, (particularly in the Pacific). While populations of olive ridleys in
the Mexican Pacific, Kemp’s ridleys in the Gulf of Mexico,
and hawksbills in the Yucatan of Mexico appear to be
recovering, thanks to more than a decade of focused protection and conservation efforts, other populations, such as
Caribbean green turtles, are still in dire straits. Nevertheless, Cuba and Dominica are proposing to reopen international trade.
33
WHAT WWF IS DOING FOR MARINE TURTLES
In Central America, WWF is working to encourage local
communities and fishermen to protect turtles through use of
TEDs. Other initiatives include campaigns to keep trash
such as plastic bags and twine from banana plantations out
of rivers and oceans. WWF is also encouraging establishment of wildlife refuges and sanctuaries and supporting
patrols on turtle beaches. In addition, WWF is supporting
measures to reduce the harmful effects of street lighting near
beaches. On the trade front, the organization is working to
halt the sale of tortoiseshell products and bring poaching
activities to the attention of the authorities.
A major effort to conserve marine turtles in the Central
American region is being made through the Central
American Environment Programme (Programa Ambiental
Centroamericano – PROARCA) which seeks to promote
integrated coastal management and protected areas programmes. PROARCA is carried out in partnership with the
Central American Commission for Environment and Development and supported by the US Agency for International
Development. It is implemented by The Nature Conservancy, WWF, and the University of Rhode Island. Since
1995, WWF has focused its activities on two areas: the
Miskito Coast in northeast Nicaragua and the Gulf of Fonseca, which is shared by Honduras, Nicaragua and El Salvador. At both sites, WWF is working closely with local communities to promote sustainable use and management of
coastal resources, including marine turtles. In the Gulf of
Fonseca, WWF is working with the three governments to
secure a network of ten protected areas.
WWF is also expanding its programme to bring about a
“sea change” in national and international policy in the
region regarding turtles. WWF supported a study by the
Costa Rican Environmental Law Centre, which was followed-up by a Regional Marine Turtle Conservation Workshop held in Tortuguero, Costa Rica, in 1998.
WESTERN ATLANTIC – THE WIDER CARIBBEAN
Because turtles are highly migratory, a decline in a local population may be a direct consequence of human activity hundreds or even thousands of kilometres away. The proposals
made at the 1997 CITES Conference of Parties to reopen
trade in hawksbill products thus have region-wide implications and will only add to the long list of serious and growing
threats from human activities. Within the Wider Caribbean,
WWF has addressed this and other threats to the region’s
six endangered species of marine turtles. One of the first
steps taken by WWF was its co-sponsoring a meeting in
November 1999, Marine Turtle Conservation in the Wider
Caribbean: a Dialogue for Regional Management. Recommendations arising from this meeting will be used to implement regional consensus about marine turtle conservation
identifying actions needed for their recovery, and ways gov-
34
ernments could cooperate to undertake these actions.
Other WWF initiatives include measures to develop a network of protected areas within the MesoAmerican Caribbean
Reef Ecoregion to protect critical habitat (mangroves, seagrass beds and coral reefs) for hawksbill and green turtles.
GUYANA SHIELD ECOREGION
WWF has been supporting marine turtle conservation in the
Guyanas since the 1960s. This biologically rich area comprising Guyana, Suriname, French Guyana, and part of
Venezuela, Colombia and Brazil, has many important turtle
nesting beaches along its coasts. Suriname is host to four
species, including the only remaining nesting population of
the olive ridley in the western Atlantic. The imminent
extinction of the olive ridley makes protection of this area of
prime importance. The leatherback population nesting in
Suriname and French Guyana has increased over the past 30
years and is probably the largest in the world. The nesting
population of green turtles appears to have stabilized.
Through a number of initiatives, WWF is confronting
threats from the shrimp industry, overharvesting, and erosion of nesting beaches. A Regional Marine Turtle Conservation Programme is being implemented from WWF’s
newly established office in Paramibo, Suriname. Other current activities include conservation measures in Suriname’s
Galibi Nature Reserve, where thousands of green turtles
come ashore to nest, and at sites in French Guyana. WWF is
also continuing its long-running support for conservation
efforts at Hattes beach, French Guyana, which hosts 15,000
to 20,000 nesting female leatherbacks each year, and has
recently been declared a reserve.
Brazil
WWF provides support to Projecto TAMAR, the Brazilian
national sea turtle programme. A “mini-guide” project has
been developed in which schoolchildren between 8 and 13
years old learn about marine ecosystems and sea turtle ecology, and ways of protecting the turtles. After the course, the
children are given the chance to work as interns at the
TAMAR visitor centre at Praia do Forte, where they inform
tourists about sea turtles and help biologists in field activities. Their involvement not only gives them valuable skills
for interacting with tourists, but also an extra source of
income.4 WWF is also supporting conservation efforts at
Noronha Island on the northeast coast, where three million
hatchlings have been released over the past 19 years.
Costa Rica
WWF is supporting the ANAI Association, a local NGO, to
protect Gandoca beach and its leatherback, green and
hawksbill turtle rookeries. Last year, 449 volunteers helped
to relocate clutches from vulnerable nests to hatcheries,
WHAT WWF IS DOING FOR MARINE TURTLES
camouflage other nests, and count turtles. By providing
lodging for these volunteers, the local community earned
four times more than they would have earned from the
illegal selling of turtle eggs.
Anguilla
WWF has supported the Anguilla National Trust to manage
their sea turtle conservation programme, which included a
survey of turtle nesting beaches. Anguilla imposed a fiveyear moratorium on harvesting of both adult turtles and eggs
in 1995, but the number of nesting turtles is still declining. In
the last few years, more young hawksbills and greens have
been seen in Anguillan waters, but the conservation effort
will have to continue for many more years before populations begin to recover.
Venezuela
WWF’s associate in Venezuela, FUDENA, has worked for
two decades on sea turtle conservation on the Isla de Aves
and in the Laguna de Tacarigua National Park. The organizations activities on Isla de Aves include yearly monitoring
and tagging of females during their nesting period. FUDENA’s “Adopt a Sea Turtle” campaign helps to support this
programme. In Laguna de Tacarigua, FUDENA collaborates with several partners to involve local communities in
protection of sea turtle nests.
NORTHERN ATLANTIC
Canada
Mauritania
The Banc d’Arguin National Park, an important nesting and
feeding ground for green and loggerhead turtles, has been
supported by WWF since 1976. Observers estimate that several thousand turtles are killed each year as bycatch in the
offshore shark fisheries. It is hoped that WWF’s work on
fisheries management will have a positive impact on
solving this problem. Tag recoveries show that the Banc
d’Arguin’s green turtles come from as far away as Florida,
although others originate in the Archipelago dos Bijagos in
Guinea-Bissau.
Gabon
Marine turtles are heavily exploited along Africa’s Atlantic
seaboard, and all four species occurring along Gabon’s coast
are threatened by unsustainable harvesting of adults and
eggs, and through the bycatch of multinational fishing fleets.
Gabon hosts the second most important breeding site for
leatherbacks in the world and offshore seagrass pastures are
important feeding areas for green turtles. With the exception
of leatherbacks, which are partially protected, there are no
laws in Gabon to protect sea turtles. In northwest Gabon,
turtles are trapped with special nets; in other areas they are
killed when they come ashore to nest. In 1997, as part of a
regional action plan for turtles, WWF held a workshop in
Pointe Pongara to collate data from scientists on turtle status and define measures needed for their conservation in the
Gulf of Guinea. The workshop was timed to coincide with
the turtle nesting season so that participants could learn
field-monitoring techniques. WWF is pursuing a number of
priorities highlighted in the Marine Turtle Action Plan.
Rangers patrol waters off Mauritania’s
Banc d’Arguin National Park.
MARK EDWARDS/STILL PICTURES
Between 1824 and 1992, only 60 leatherbacks were reported
in Canadian waters. Since 1997, WWF Canada has supported a project to enlist the help of fishermen along the
southern coast of Nova Scotia. In 1998 alone,
over 200 were sighted. Thanks to this project,
more is being learnt about leatherback
distribution and movements – knowledge
that will help reduce the number of turtles
becoming entangled in fishing lines.
EASTERN ATLANTIC
2000 WWF Species Status Report
35
WWF/JEANNE MORTIMER
WHAT WWF IS DOING FOR MARINE TURTLES
Pictured here is a small “bekko” factory in Japan that produces tortoiseshell products.
Monitoring trade in turtle products
Most countries have national laws restricting turtle fishing
and egg collecting and many are members of CITES. Some
national laws do not recognize some species of marine turtle
as threatened or endangered. In Indonesia, for example, the
green turtle is not considered endangered and large numbers
are still killed for meat. Many tropical and subtropical countries allow harvesting of turtle eggs and theoretically this
harvest is controlled. But abuses often occur, in Mexico,
poachers removed 500,000 olive ridley eggs from a beach in
Oaxaca in 1996.5
TRAFFIC, the wildlife trade monitoring arm of WWF
and IUCN, documents the extent of the illegal international
trade and is working to bring violations of international
treaties to the attention of government authorities. Such violations appear to be widespread: there is still a substantial
underground trade in tortoiseshell, leather boots, whole turtles, meat and eggs. For example, customs officials made a
number of seizures of illegal turtle shells from Indonesia at
EU borders between 1990 and 1995.6 In September 1998,
police officers in Japan arrested five people attempting to
smuggle 66kg of tortoiseshell into the country.7 In the United
States, a number of arrests have been made recently at international airports in Florida, New York and California where
people have been caught smuggling turtle eggs and meat
in their luggage.8 The contraband finds its way to ethnic
restaurants, where it is sold as a delicacy at high prices. As
the trade in sea turtle eggs appears to be on the increase,
TRAFFIC is increasing its efforts to collect and disseminate
information on its extent, so that more effective protection
and management can be implemented.
TRAFFIC is also working with governments on
improving protection of species threatened by trade, even
36
where that trade is largely internal and legal. For example,
in Vietnam, large numbers of hawksbill turtles are legally
caught for meat and medicine, and their coastal habitats are
threatened by development. Numbers of tourists have been
growing steadily and stuffed hawksbill turtles and tortoiseshell products are often found for sale in local markets.
Many tourists are not aware that taking such items back to
their home countries is illegal. A 1993 to 1994 TRAFFIC
study of the effects of this trade on hawksbill populations
found that the trade was contributing to the decline of Vietnam’s hawksbills, already under threat from other factors.
As a result of this study, TRAFFIC was able to make a number of recommendations to the government of Vietnam on
suspending commercial exploitation of hawksbills.9
TRAFFIC North America is carrying out a trade
review and legal analysis of the fisheries and primarily commercial trade of marine turtles in the Bahamas, Cuba,
Dominican Republic, Haiti, Jamaica, Mexico, Puerto Rico,
Turks and Caicos Islands, British Virgin Islands, and U.S.
Virgin Islands.
WHAT WWF IS DOING FOR MARINE TURTLES
Turtle Conservation in Bali
Bali has been the world’s largest consumer of green turtles since the
1970s. Turtle meat is used particularly in the Badung and South
Denpasar areas for religious purposes and in traditional ceremonies. These practices have been in place for generations.
During the last several decades, however, there has been a
shift from using turtles within sustainable limits for ceremonial and
religious purposes, towards large-scale commercial exploitation.
WWF/ELIZABETH KEMF
The need to conserve the stock in the wild has been largely ignored;
consequently, there has been a dramatic decline as shown by the
significant decrease in the numbers of female turtles coming ashore
on Indonesian and neighbouring beaches in recent years.
WWF, working together with the office of Natural Resources
Ketut Putra, head of WWF’s marine turtle programme in Bali.
Conservation in Bali and the local government, is addressing this
problem in a number of ways. The first priority has been to record
management which only allows an annual consumption of 3,000
the numbers of turtles coming into Bali through several major
turtles per year.
ports such as Tanjung Benoa near Denpasar and Padangbai in the
WWF’s education and awareness programme focuses on the
eastern part of the island. Attention is also being given to recording
status of the turtle population, its biological profile and the laws
which species of turtles are brought to these ports as hawksbills as
protecting it. Together with local conservation groups, WWF has
well as greens are being butchered. These data include analyses of
launched a two-pronged programme to monitor the trade and,
the size of the turtles caught.
through Balinese religious, traditional and community leaders, to
A second focus is on developing and implementing a
educate devotees and young people to the fact that the green turtle
Bali-orientated education and awareness programme designed to
is endangered. In Prancak village, on the coast of west Bali, local
reach those who use turtle meat, turtle traders from outside Bali,
religious leaders have joined the awareness campaign and school-
and both foreign and domestic tourists. The goal is to reduce the
children have become “rangers” protecting turtle nests. Ex-turtle
amount of turtle meat consumed in Bali annually to within the cur-
hunters are among the many people now fighting for the survival
rent quota system. This quota, estab-
of turtles, and a number of Balinese youngsters have formed their
lished by Bali’s Governor in 1990,
own group, the Kelompok Pecinta Penyu Bali, which promises
is set at 5,000 turtles per year, but
to become a major force for turtle conservation. This
is intended to function within
programme must ultimately address ways to find
the national guidelines
alternative income sources for turtle hunters.
for turtle population
Leatherback turtle rescued at
the last minute from being killed
for sacrifice in Bali.
2000 WWF Species Status Report
WWF-CANON/KETUT PUTRA
by Ketut Sarjana Putra
37
WHAT NEEDS TO BE DONE
Six of the world’s seven species of marine turtles are
threatened with extinction. Many populations which were
abundant 100 to 200 years ago are now depleted, declining
or remnants of their former size. Local extinctions have
occurred in all ocean basins, and no population, not even
those that are stable as a result of long-term conservation
and management, is completely safe. Marine turtles present
enormous conservation challenges because they grow slowly
and require numerous and diverse habitats as they mature.
They also move great distances in their lifetimes, frequenting the waters of many nations and must come ashore to
lay their eggs.
Although marine turtles are ancient creatures, the science of marine turtle biology is relatively new. Scientists
have amassed a great deal of data about the amazing life history of these animals, but as one set of questions is answered,
new ones emerge. In recent years powerful new tools, such
as genetic analysis and satellite telemetry, have been developed to answer the riddles surrounding marine turtles, but
much remains to be discovered, and much needs to be done.
The following activities need to be undertaken:
hat
needs to
be done
Carry out long-term conservation action
Clear and comprehensive conservation programmes are
needed everywhere if marine turtles are to survive well into
the future. Ensuring many populations recover to abundance (so that turtles can fulfill their ecological roles in the
marine environment) is a necessary goal.
Recognizing that regional cooperation and collaboration are essential to marine turtle conservation and management, resource managers have started international initiatives, collaborating with near and distant neighbour
nations. More is needed.
Long-term commitments to conservation are essential.
Those started long ago are reaping rewards. Some depleted
nesting populations, such as green turtles in Malaysia, loggerheads and leatherbacks in South Africa, and hawksbills
and Kemp’s ridleys in Mexico, have stabilized and increased
in recent years. But this is after more than two decades of
protection and management. While the future of these populations remains tenuous, their improved status demonstrates the value of focused conservation efforts.
WWF/ARQUIVO PROJECTO TAMAR
Develop regional conservation and management
programmes
Leatherback returning to the sea after nesting in Brazil.
38
Marine turtle conservation and management need to be
addressed regionally so that activities in one area do not
undermine (but complement) programmes in others. Breeding and feeding areas are often widely separated, and within
each region, critical nesting, foraging, resting and migration
areas for each species must be identified and formally protected. Conservation hotspots in each region should also be
identified so that attention can be focused on resolving prob-
WHAT NEEDS TO BE DONE
lems, such as overexploitation of feeding grounds in one
country where turtles from other nations may congregate.
Regional agreements that provide legal frameworks, such as
the Inter American Convention for the Protection and Conservation of Sea Turtles and an initiative in the Indian Ocean
to negotiate a treaty for marine turtles, need to be supported. Successful regional programmes must involve the
participation of numerous sectors and include participants
from the local to national to international level. To date,
regional networks of biologists, conservationists, and
resource managers have evolved in Southeast Asia, the
South Pacific, the Mediterranean, Latin American, and the
wider Caribbean, while new groups are emerging in the
northern and western Indian Ocean, Arabian Gulf and
Eastern Atlantic. These networks need to be strengthened,
thus ensuring that cooperation, collaboration and the sharing of information, such as through regional databanks,
should be promoted on all levels. Financial support from
governments and donor organizations is also needed.
Reduce accidental capture in fisheries
After the shrimp trawl fishery was identified as a major
source of mortality in the early 1980s, net inserts or Turtle
Excluder Devices (TEDs) were developed to allow
entrapped turtles (and other bycatch) to escape. Although
TEDs are used widely in the western hemisphere, they are
not employed extensively in shrimp and other trawl fisheries
around the world. Mortality in longline fisheries for pelagic
species such as swordfish and tuna is a grave and increasing
threat, as these fisheries, which set billions of hooks each
year, continue to expand. Marine turtles swallow longline
hooks or become entangled in lines and drown. Many animals that are released alive but with hooks embedded in
their gastro-intestinal tracts subsequently succumb to their
injuries. Modifications to hooks and bait, as well as area and
seasonal closures, will be needed to address this problem satisfactorily. Marine turtles are also captured and drowned in
various gill net fisheries and in the lines of fish traps. Programmes to reduce mortality through modified gear and
fishing techniques, or closing particular areas at particular
times, are needed. Fishermen should be encouraged to assist
in these efforts.
Enforce CITES, laws and agreements
Most species of marine turtles have been prohibited from
international trade since 1975 when CITES came into force.
By 1981, all marine turtle species were listed on Appendix I
of CITES. This list prohibits trade by all CITES member
nations. However, Japan continued to import large quantities of green, olive ridley and hawksbill products until the
early 1990s under “reservations” or exceptions to the CITES
listing. In 1992, Japan agreed to comply with CITES and
stop marine turtle trade and retrain the bekko or tortoise-
2000 WWF Species Status Report
shell artisans. Today, more than 140 countries have acceded
to CITES, but tortoiseshell jewellry, turtle oil and stuffed
turtle curios are still entering international trade. Marine
turtles and their parts are sold in tourist markets and international airports in many areas of the western hemisphere
and Asia. WWF encourages CITES member nations to stop
illicit international trade and urges all countries to pass
and implement national laws and regional agreements to
conserve marine turtles.
Protect marine turtle habitat
Marine turtles move in and out of ocean and coastal habitats
as they grow and mature. Although crucial nesting and foraging habitats can be conserved within national parks and
marine protected areas, other areas utilized exceed the
capacity of any government to provide full protection.
Marine turtle conservation requirements should be included
in coastal zone management plans as well as ecosystem conservation programmes. Regulations for maintaining water
quality and contingency plans for oil and chemical spills are
critical to maintain the health and productivity of the ecosystems on which marine turtle depend. The threats posed by
dynamite fishing, marine debris, and oil pollution should be
eliminated. Where necessary, legislation must be encouraged, such as lighting restrictions on nesting beaches. Erosion, accretion, sand mining, and foot and vehicular traffic
on nesting beaches also need to be addressed to ensure that
nesting females, eggs and hatchlings are protected. Longterm monitoring programmes are also critical to assessing
the impact on these habitats.
Support development of sound ecotourism based
on marine turtles
Sound ecotourism not only benefits local guides, food vendors, and small hotel operators, but, as shown by the cooperatives run by Projecto TAMAR in Brazil, can also help
support entire communities. In Tortuguero, Costa Rica, the
village’s major source of income is generated by tourists who
visit the area to see its famous green turtles: in recent years
the influx of visitors has enabled the community to install
electricity and other modern amenities. These programmes
demonstrate that living marine turtles can be more beneficial to coastal communities as “renewable” resources rather
than harvested resources which are only used once.
Develop guidelines for use
Recognizing that some communities are dependent on
marine turtles and their eggs, WWF supports the need to
develop guidelines for use, with the goal of ensuring use is
sustainable and these programmes benefit local coastal people. Opinions vary about what constitutes sustainable use of
marine turtles. Thus, in developing guidelines, resource
managers and biologists have to address the status of the
39
WHAT NEEDS TO BE DONE
population within its full range. Various approaches will
need to be explored, such as weighing the value of an adult
female for her production of eggs versus meat or harvesting
nesting turtles that come ashore after a number of breeding
seasons. In many countries harvest regulations focus on the
wrong part of the population because they protect sub-adult
turtles at the expense of adult breeders. Although egg
collection is less controversial, these programmes are not
without problems, as in the case of an authorized egg collection for one species that jeopardizes the eggs of other species
needing full protection. Egg collection programmes need
to be flexible enough to ensure that a sufficient proportion
of eggs successfully hatch each year.
REFERENCES
History and Culture
Clark, E. E. 1979. Indian Legends of Canada, Mc Clelland
and Stewart, Toronto, Canada.
Devaux, B. 1991. La Tortue, Robert Laffont, Paris, France.
Parsons, J. 1972. The Hawksbill Turtle and the Tortoiseshell
Trade, Etudes de géographie tropicale offertes à Pierre
Gourou, Mouton. Paris. La Haye.
Pritchard, PCH 1990. The Turtle Planet, Ironwood Video,
USA.
Witzell, WN 1983. Synopsis of Biological Data on the
Hawksbill, Food and Agricultural Association of the United
Nations, Rome, Italy.
Support sea turtle research
Many gaps in our knowledge of marine turtle biology still
exist, such as how many hatchlings survive to reach maturity
or how long marine turtles live. While “full knowledge” is
not necessary to make many informed decisions about conservation and management, additional research is needed
about factors that affect health, reduce reproductive output,
or address the ecological roles of marine turtles in their environment. For example, in the last ten years, scientists have
become increasingly concerned about the impact of fibropapillomas, debilitating and life-threatening tumour-like
growths found in all species, but especially in green turtles.
The effects of pathogens, pollutants and climate changes on
sea turtles also need to be determined. While it is impossible
to determine how depleted populations may have functioned when they were more abundant, studies demonstrate
that nutrients from turtle eggs and egg shells play a critical
role in maintaining the roots of beach grass and the stability
of the associated dune ecosystem while offshore seagrasses
regularly grazed by green turtles are more productive.
Promote public awareness and education
For many populations of marine turtles around the world,
the day-to-day support of local coastal communities is crucial to their survival. Public awareness and educational programmes to instill understanding and appreciation are the
cornerstones of local and national initiatives to conserve
marine turtles. In Greece, for example, programmes developed by Archelon – the Sea Turtle Protection Society, reach
thousands of school children and visitors to turtle beaches
each year. This growing public awareness has enabled the
government to establish the National Marine Park of Zakynthos, a major loggerhead nesting area in Greece. Other sectors of society that need to be targeted include developers,
industrialists, and the media. Only by understanding the
needs of marine turtles will they be encouraged to address
the threats these species face.
40
Natural History
(1) WWF Mediterranean Programme 1998. Marine Turtle
Conservation Management in the Mediterranean –Recommendations for a New Approach. 16pp.
(2) Laurent, L. 1998. Conservation Management of Mediterranean Loggerhead Sea Turtle Caretta caretta Populations.
WWF International Project 9E0103. WWF International
Mediterranean Programme, Rome.
(3) Yerli, S., and Demirayak, F. 1996. Marine Turtles in
Turkey: a survey on nesting site status. Coastal Management
Report 96. DHKD, Istanbul, Turkey.
(4) Vieitas, C.F., Lopez, G. and Marcovaldi, M.A. 1999.
Local community involvement in conservation – the use of
mini-guides in a programme for sea turtles in Brazil. Oryx
33(2) pp. 127- 131.
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