|
|
|
|
|
|
|
|
Project Elephant
Project Tiger
Crocodile Conservation
Sea Turtle Conservation
Blackbuck Conservation
Similipal Biosphere Reserve
Nandankanan
Chilika
Bhitarkanika
Mangroves
Vision for the Future
Organisation
Man-Wildlife Interface
Eco Tourism Destination
Wildlife Census
Wilset
Feed Back
Contact Us
 
 
   


ECOLOGICAL CONDITIONS FAVOURABLE FOR SEA TURTLES
In coastal Odisha, the area of confluence of any river and the sea, which is the deltaic region, is a fascinating ecosystem. Also called intertidal area, this is criss-crossed by estuary, rivers, creeks and creeklets. The land in these estuaries is continually inundated by the saline sea water under influence of sea tide and also sweet water of river. Such lands are covered with mangroves, a kind of vegetation endemic to these areas. The mangroves and the estuaries are the breeding and spawning grounds of varieties of marine life forms such as fishes, prawns, crabs and mollusks. These life forms spend their juvenile stage in the mangrove estuarine ecosystem, and migrate to the sea in the later part of their lives. October to May is the period during which these juveniles are available in abundance in the estuaries and the coastal sea. This is the time for the sea turtles to congregate in these areas, having migrated over large distances in the sea to feed on these fishes etc. in the shallow sea near the intertidal regions. During the months of October to May therefore, shallow sea near the river mouth becomes the feeding ground of the sea turtles, both for the adults and their juveniles. The sea turtles congregate and mate there and then look for suitable undisturbed beaches in these river mouth areas for laying eggs and nesting.
Based on these ecological conditions, certain pockets in the Odisha coast have become the famous mass nesting sites of the Olive Ridley sea turtles. Significant populations of these turtles visit the congregation areas en-masse before the winter months for breeding and nesting. This is a yearly phenomenon. This population represents about 50% of the total world population of Olive Ridleys, and about 90% of the Indian population of sea turtles. Worldwide attention is naturally focused on these rookeries for conservation of this species.

ECOLOGICAL CONDITIONS FAVOURABLE FOR SEA TURTLES
In coastal Odisha, the area of confluence of any river and the sea, which is the deltaic region, is a fascinating ecosystem. Also called intertidal area, this is criss-crossed by estuary, rivers, creeks and creeklets. The land in these estuaries is continually inundated by the saline sea water under influence of sea tide and also sweet water of river. Such lands are covered with mangroves, a kind of vegetation endemic to these areas. The mangroves and the estuaries are the breeding and spawning grounds of varieties of marine life forms such as fishes, prawns, crabs and mollusks. These life forms spend their juvenile stage in the mangrove estuarine ecosystem, and migrate to the sea in the later part of their lives. October to May is the period during which these juveniles are available in abundance in the estuaries and the coastal sea. This is the time for the sea turtles to congregate in these areas, having migrated over large distances in the sea to feed on these fishes etc. in the shallow sea near the intertidal regions. During the months of October to May therefore, shallow sea near the river mouth becomes the feeding ground of the sea turtles, both for the adults and their juveniles. The sea turtles congregate and mate there and then look for suitable undisturbed beaches in these river mouth areas for laying eggs and nesting.
Based on these ecological conditions, certain pockets in the Odisha coast have become the famous mass nesting sites of the Olive Ridley sea turtles. Significant populations of these turtles visit the congregation areas en-masse before the winter months for breeding and nesting. This is a yearly phenomenon. This population represents about 50% of the total world population of Olive Ridleys, and about 90% of the Indian population of sea turtles. Worldwide attention is naturally focused on these rookeries for conservation of this species.

The Crocodile Project started with the objective of building the population to a stage when incidence of sighting could be 5 to 6 crocodiles per KM length of water. The Project sought to make up the natural losses by death and predation through rear and release operation. This involved collection of eggs from the nests as soon as these were laid, incubation and hatching of these eggs in hatcheries under regulated conditions of temperature and humidity, rearing the young juveniles, marking and release of the young crocodiles into Nature in protected areas, and assessment of the degree of success in restocking any protected area with crocodiles released from the hatcheries. To accomplish these tasks, 3 separate research units were established at Tikarpara, Dangmal and Ramatirtha for the Gharial, Salt Water Crocodile and the Mugger, respectively. At the Nandankanan Biological Park, captive breeding plans for all three species were pursued.


The Olive ridleys are Schedule I species under the Wildlife (Protection) Act, and are listed as 'endangered' in the IUCN Red Data Book, in the 'Appendix-I' of CITES (Convention on International Trade in Endangered species of wild Flora and Fauna), and also listed in the CMS (Convention on Migratory species). India being a signatory nation to all these conventions has the responsibility of protecting this species of sea turtle and its nesting beaches, breeding, feeding and congregation areas, as well as its migratory pathways in the sea.

During the period from October to early summer, shallow seas near the river mouths become ideal feeding grounds for the Olive Ridley Sea turtles. At these places they also breed and look for undisturbed beaches for nesting.

The known major breeding grounds in Odisha where such congregation takes place are located near the river mouths off Dhamra, Devi, and Rushikulya, although there are also minor breeding grounds near other river mouths such as the Mahanadi, Subarnarekha, Budhabalanga, Keluni and Bahuda.
The famous mass nesting site of Olive Ridleys close to the mouth of Brahmani-Baitarani (Dhamara), received worldwide recognition in 1975-76 as one of the largest rookeries of the Ridleys.



THREATS
The sea fishing activities have direct adverse impact on the adult sea turtles and their hatchlings. Olive ridleys usually mate between October to February, when they congregate in the shallow coastal waters for prolonged periods, making them vulnerable to the fishing nets and propellers of the trawlers.
The other threats to sea turtles include: (i) Loss or modification of the nesting beaches due to Casuarina plantation; (ii) Fishing by gill nets; and development of fishing bases at the potential nesting sites and breeding areas; (iii) Strong illumination around nesting beaches which greatly disorients the adult turtles as well as the hatchlings; (iv) Large scale vessel movement in congregation zones severely disturb mating and breeding; (v) Nests and eggs are destroyed by predators like dogs, jackals, hyenas, etc., and by beach erosion.
The most significant of these threats is 'incidental catch' in marine fisheries (where a few thousand turtles are killed in trawl and gill nets every year), as well as depredation of turtles eggs by feral and wild predators.
To

POPULATION ESTIMATE OF NESTING SEA TURTLES

Population Estimation Technique

Recorded figures of the number of turtles which laid eggs in different rookeries and the number of turtle casualties detected in different years are as follows:

 

Year

No. of  Nesting Turtles at Rookeries (in lakhs)

No of turtle casualties detected along the Odisha coast during the year

Fishing vessels seized in Gahirmatha Marine Sanctuary

Gahirmatha

 

Devi

Rushikulya

1998-99

2.98

Not counted

No mass nesting

13,671

50

99-2000

7.11

25,000

No mass nesting

15,732

18

2000-01

7.41

No mass nesting

1.59

5,483

37

2001-02

No mass nesting

No mass nesting

0.35

12,977

135

2002-03

0.73

No mass nesting

2.08

10,086

63

2003-04

2.43

No mass nesting

2.01

4,981

37

* Gahirmatha: (Dhamara river mouth to Mahanadi river mouth)

PROGRAMMES AND ACTIVITIES:
* Declaration of Gahirmatha Marine Wildlife Sanctuary in September, 1997.
* Formation of State Level Steering Committee for sea turtles under the chairmanship of Chief Secretary, Odisha in 1997.
*Declaration of three major turtle congregation sites (nesting and breeding grounds) at Gahirmatha (Dhamara river mouth), Devi and Rushikulya River mouths as 'No Fishing Zones' during the reproductive and nesting period.
*Use of 'Turtle Excluder Device' (TED) has to be mandatory in all trawl fishing nets.
*Regular patrolling of the nesting beaches and congregation-breeding zones in the sea by setting camps along the sea coast, and by patrolling in sea by trawler.
*Monitoring the nesting beaches against predators and human interference.
*Motivating local people in conservation of the breeding and nesting turtles.
*Awareness creation among the fishing community and local inhabitants

Conservation highlights during 2003-04

· The nesting beaches were protected from biotic interference, and efforts have been made to keep them in proper condition for nesting of sea turtles and safe emergence of the hatchlings.
· Monitoring has been done by setting of camps at strategic locations on the shore to cover all nesting areas. 26 camps were set up covering 44 nesting beach segments on the entire Odisha coast.

· A Central Monitoring Unit (CMU) functioning in the office of Chief Wildlife Warden, Odisha coordinates and monitors day to day activities relating to Sea turtle conservation.
· Sea patrolling was launched from six offshore camps. Prohibition against trawl and gill net fishing was enforced in the turtle congregation zones in the coastal sea by taking up patrolling of these areas.

· VHF communication among the camps and forest offices in the coastal area was strengthened through 15 VHF Main sets and 12 Handsets. · Joint patrolling was done involving the Coast Guard and State Fisheries Department.

· A total of 37 fishing vessels / boats which were doing illegal fishing in the prohibited zone were seized and kept in the custody of forest officials and legal action has been initiated against the offenders.


Copyright © 2007 - 08 Wildlife Conservation (Odisha), All Rights Reserved