Turtles, Its status and Conservation
Avinash Rasal,Prabhakar Nikumbe, Sachin Khairnar*, Amod Salgaokar,Trivesh
Mayekar, Pankaj patil**, Roshan Akhade**
of Fisheries Education, Mumbai 400 061
of India, Mumbai
fisheries, Shirgaon, Ratnagiri, Maharashtra.
Indian turtle, along with tortoise and
terrapin, belongs to the Testudines order of reptiles and the Chelonia crown
group. The body of a turtle is covered with special bony or cartilaginous
shell, which is developed from its ribs. One of the oldest reptile groups, the
turtle of India was in existence even before lizards and snakes. Some of the
species of the Indian turtles have become extinct, while a number of others
have become highly endangered. Turtles are cold-blooded creatures i.e., their
body temperature changes with their surroundings. The size of an Indian turtle
tends to vary a lot, with marine turtles being bigger than land and freshwater.
Cryptodira and Pleurodira
Types of Indian Turtles
- Olive Ridley Turtle (Lepidochelys olivacea)
- Green Sea Turtle (Chelonia mydas)
- Hawksbill Turtle (Eretmochelys imbricate)
- Leathery Turtle (Dermochelys coriacea)
- Eastern Mud turtle (Kinosternun subrubum subrubum)
Although many turtles
spend large amounts of their lives underwater, all turtles and tortoises
breathe air, and must surface at regular intervals to refill their lungs. They
can also spend much of their lives on dry land. Aquatic respiration in
Australian freshwater turtles is currently being studied. Some species have
large cloacal cavities that are lined with many finger-like projections. These
projections, called "papillae", have a rich blood supply, and
increase the surface area of the cloaca. The turtles can take up dissolved
oxygen from the water using these papillae, in much the same way that fish use
gills to respire.
Turtles lay eggs, like
other reptiles, which are slightly soft and leathery. The eggs of the largest
species are spherical, while the eggs of the rest are elongated. Their albumen
is white and contains a different protein than bird eggs, such that it will not
coagulate when cooked. Turtle eggs prepared to eat consist mainly of yolk. In
some species, temperature determines whether an egg develops into a male or a
female: a higher temperature causes a female; a lower temperature causes a
male. Large numbers of eggs are deposited in holes dug into mud or sand. They
are then covered and left to incubate by themselves. When the turtles hatch,
they squirm their way to the surface and head toward the water. There are no
known species in which the mother cares for the young.
Sea turtles lay their
eggs on dry, sandy beaches. Immature sea turtles are not cared for by the
adults. Most are endangered largely as a result of beach development and over
harvesting. Turtles can take many years to reach breeding age, and in many
cases breed every few years rather than annually.
have recently discovered a turtle's organs do not gradually break down or
become less efficient over time, unlike most other animals. It was found that
the liver, lungs and kidneys of a centenarian turtle are virtually indistinguishable
from those of its immature counterpart. This has inspired genetic researchers
to begin examining the turtle genome for longevity genes.
Current Status of turtle
species in India
legal protection given to all sea turtle species in India, in recent years the
populations migrating to Indian waters are on the decline. Several thousand
adult breeding individuals die every year along the Indian coastline, and have
become a major concern of national and international community (Pandav et al.
1997, Pandav & Choudhury 1999). The repercussions of such large scale
mortality of a globally migratory species group has had its reflection at the
WTO, where India contested a ban that was imposed by the USA on the export of
marine products caught with gear that did not address sea turtle mortality.
Known nesting beaches
Goa, Karnataka and Kerala
Olive ridley and Leatherback
ridley and Green
Gujarat: Mandvi in Kutch, Sea beach between Okay and Okha Madhi, Bhaidar, Beyt,
Nora and Chank Islands.
Maharashtra: Olive ridley nest near Gorai, Kihim, Manowrie and Versova.
(West Bengal, Orissa, Andhra Pradesh and Tamil Nadu)
ridley, Green, Hawksbill, Leatherback and Loggerhead
Tamil Nadu: Nest in Gulf of Mannar, Point Calimere, and 50 km coastline south of
Andhra Pradesh: Kakinada
coast, sea beach near the mouth of Godavari and Krishna and near
Orissa: All along the
coast south of Dhamra river mouth. Two mass nesting beaches at Gahirmatha
West Bengal: In the
sandy beaches of Sunderbans.
(Andaman & Nicobar
Islands and Lakshadweep)
ridley, Green Leatherback, Hawksbill and Loggerhead
ridley, Green, Hawksbill and Leatherback
Nicobar, Little Andaman, Rutland, Middle Andaman, Katchal, South
Sentinel, south Reef and Teris Islands
Table I: Nesting sites for
sea turtles in India
The small-scale research, conservation and management
of sea turtles in India, which dates back to the mid 1970's, culminated in the
mid 1980's with the active participation of the Indian Coast Guard and Navy in
sea turtle protection. However, sea turtles, which spend almost six months each
year along the Indian coastline, face a multitude of problems in need of
address. The major problems that sea turtles face in Indian coastline include:
1. Non-human predation: A significant proportion
of nests are subjected to heavy predation. Studies on the population dynamics
of the Olive ridley at Gahirmatha rookery, along northern Orissa coast, have
indicated that a large percentage of eggs laid during each nesting season are
destroyed (Dash & Kar 1990). This results from destruction of nests by
other females during an arribada, nest
destruction by wild pigs, jackals, and feral dogs, and by beach erosion (Pandav
et al. 1994). Feral dogs and wild pigs cause considerable damage to the nests
of Leatherback, Green and Hawksbill turtles in Andaman (Bhaskar 1993).
capture in fishing nets: Near-shore mechanized fishing within 5 km from the
shoreline results in the mortality of large numbers of sea turtles along the
Indian coast every year. More than 5,000 dead Olive ridley sea turtles were
counted along 480 km of the Orissa coast during a six month survey in 1994
(Pandav et al. 1994). The ongoing research programme of the Wildlife Institute
of India (WII) documents a three-fold increase in this number during 1997-98
along the same stretch. These deaths were due to accidental capture in trawl
nets, although details of the incidental capture of marine turtles in fishing
nets along rest part of Indian coast are yet to be documented.
of nesting habitats: Development activities close to the coast such as
construction of roads, tourist resorts and aquaculture projects result in the
loss of nesting habitats. Besides this, plantations of Casuarina close to some of the major sea turtle nesting beaches
has resulted in a drastic decline of the nesting population. The plantations
reduce the space available for sea turtles to nest, and once the Casuarina grows it changes the beach topography with its lifter
deposition and root growth, rendering the beach unsuitable for turtles nesting
(Pandav et al. 1994). Further, legislation which is supposed to protect nesting
sites of turtles and other marine life does not include sites presently and
historically known as breeding grounds. There are no legal guidelines for
discussion among concerned authorities and local villagers to develop a more
suitable non- forested coastal area protection program.
4 Artificial illumination: Many
of the major sea turtle nesting beaches are now subjected to bright
illumination. Artificial illumination from development activities near nesting
beaches has resulted in disorienting adult nesting sea turtles as well as
hatchlings, leading to heavy hatchling mortality (Pandav et al 1998).
Olive ridley turtle
The olive ridley sea turtle nests at several sites in
the western Indian Ocean, Indian subcontinent and Southeast Asia. The single
most important breeding area for olive ridleys in the Indian Ocean along the
Bay of Bengal is Orissa. The Olive ridley is the most numerous among the sea
turtles found in India and is well known for its arribadas, or annual mass nestings when thousands of turtles
migrate to the breeding ground to nest simultaneously. Of the few such mass
nesting beaches left in the world today where arribadas occur, India has three. A significant proportion of
world's Olive ridley population migrate every winter to the Indian coastal
waters to nest on these beaches in Orissa, as well as along other parts of
In 1993, biologists from the Orissa Forest Department
and the Wildlife Institute of India learned that large scale nesting of olive
ridley turtles was taking place near the mouth of the Rushikulya river. This
area is the location of one of the largest mass nesting (arribada) sites of
olive ridley sea turtles in India.
conservation agenda of Project Sea Turtle, Government of India
The 8129 km
coastline of India, with its high human population density and their utilization
of the diverse marine and coastal resources makes it difficult to develop a
conservation management strategy for sea turtles. The Indian Wild Life Protection
Act (1972), Amendment 2002, has a provision of declaring certain wildlife areas
as Community Reserve (CR). However, in
light of the fact that the Indian coastal environment harbors almost 30-40 % of
world's Olive ridley sea turtle population, the Government of India has
launched PROJECT SEA TURTLE at a national level. The main objectives of the
project are to:
- Prepare an inventory map of breeding sites, both
verified and others to be surveyed along the Indian coasts. These areas
would be placed under CRZ-I categories, accordingly in State and UT
Government's CRZ plans and maps.
- Identify areas along the coast, both on landward
side and seaward side, to be protected and managed as the nesting and
breeding habitats along the shore line.
- To establish guidelines for developing
infrastructure facilities, so as to safeguard and minimize the large scale
mortality of breeding sea turtles both on- and off-shore.
- Identify the migratory routes taken by sea
turtles in Indian territorial waters and beyond (if necessary with other organizations
active in this field). Annual migration charts are to be developed and
sent each year to all coastal management authorities and other agencies
involved in coastal resource use.
- Network and develop national and international
inter-agency co-operative and collaborative action for sea turtle
- Develop infrastructure and human resources for
sea turtle conservation that will also take care of other coastal
- Priorities areas, agencies and action (both
short-term and long-term) for a sustained sea turtle conservation program.
- Carry out extensive and exhaustive 5-year
surveys of the coastal area at the appropriate nesting times to verify
potential sites of turtle breeding.
guidelines for tourism in sea turtle areas, indicating the permissible and
prohibited activities (most of these can be given legal protection from
existing laws and regulations).
To meet the project
objectives the following strategy is planned to be adopted.
To train and dedicate staff
of the wildlife wing of nine coastal States and the Bay Islands to take up a
survey and demarcation of nesting beaches within their geographic locality,
which could be carried out by the WII in association with select agencies.
Thereafter, protection and monitoring of the nesting beaches could be taken by
individual State wildlife wings with technical support from an expert group.
Based on this a system of annual population monitoring and analysis plans would
be developed. Research centres to study breeding, feeding and migration biology
of these species could be initiated. Migration routes of the turtles would be
charted and monitored in a systematic manner so that future management
strategies evolve through them but based on them.
To enhance effective
off-shore patrols and protection of sea turtles through (a) wildlife wings of
coastal States and Bay islands, (b) State maritime fisheries departments and
(c) Indian Coast Guard, by providing them with adequate infrastructure. For
this purpose the Ministry of Environment and Forests (MoEF) is to organize a
consultative meeting to assess requirements.
To enforce the use of
Turtle Excluder Devices (TEDs) in trawl nets to minimize fishery-related sea
turtle mortality. The Ministry of Environment and Fisheries MoEF, Commerce and
Agriculture ministries will develop an advertisement and extension programme
for TED demonstration and subsidised supply of TEDs to trawl operators.
To initiate and upgrade
sea turtle research and monitoring and develop a suitable database, the MoEF
will lease with the Department of Ocean Development, University Grants
Commission and Commerce Ministry to support agencies such as the WII, the
Central Marine Fisheries Research Institute (CMFRI), the National Institute of
Oceanography (NIO) and coastal Universities, to set-up a suitable research
programs. Additionally, the MoEF will also priorities management-related
research topics in consultation with WII, CMFRI, NIO, wildlife wings of coastal
States and Islands and select universities.
To develop a national sea turtle conservation education and awareness
campaign. In consultation with Centre for Environmental Education (CEE), WII
and select media group, a national level long-term sea turtle conservation
education awareness campaign will be developed. Local NGO's will be encouraged
to initiate action on this issue.
Revive and strengthen
the Indian sea turtle expert group for technical advice and evaluation of
Develop a participatory
nesting beach protection and management programme with people participation,
and where benefits will reach the local people. A suggested protocol for this
is to bring adjoining villages together and create a Turtle Protection and
Village Development fund through development of a seasonal eco-tourism
activity. Benefits of such tourism should go directly to the human residents of
these sites where planned tourism is involved.
Regional and International Agencies in developing sea turtle Conservation
programs. The MoEF plans to initiate dialogue with organizations such as the
Convention of Migratory Species (CMS), United Nations Development Programme
(UNDP), and South Asia Association for Regional Co-operation (SAARC) and ASEAN
for developing a cross-sectional and integrated Coastal Resource management
program, where sea turtles feature in a significant manner.
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Kar, CS. & S. Bhaskar, 1982. The status of Sea
turtles in the eastern Indian Ocean. In The Biology and Conservation of Sea Turtles (K. Bjorndal, ed.)
Smithsonian Press, Washington DC: 365-372.
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