IN449
Car Nicobar


Site description (2004 baseline):

Site location and context
The Nicobar Islands in the Bay of Bengal are peaks of a submerged mountain range extending from Myanmar to Sumatra. The Nicobar group comprises of 23 islands covering an area of 1,841 sq km. Of these only 12 are inhabited. The Nicobar group of islands can be divided into three, the Great Nicobar, the Nancowry subgroup and the Car Nicobar subgroup (Sankaran 1998). Car Nicobar, along with Batti Malv, is part of the northernmost subgroup of the Nicobar Islands. They lie about 88 km north of the Nancowry subgroup. While Car Nicobar is inhabited, Batti Malv is not. The human population of Car Nicobar is over 19,000, of which more than 80% are tribals. Proximity to the equator and the sea ensures a hot, humid and uniform climate. The Islands receive rainfall from both the southwest and the northeast monsoons. The maximum precipitation is between May and December, the driest period being between January and April (Sankaran 1995). The forest type of the Nicobar Islands can be classified as tropical evergreen, with inland areas being forested or grasslands and a significant proportion of the coast being mangroves. In the Car Nicobar subgroup, Batti Malv is forested, while most of Car Nicobar bears coconut plantations or forest, with a small area under grassland (Sankaran 1998).

Key biodiversity

AVIFAUNA: One globally threatened species, which is also a Restricted Range species, Nicobar Sparrowhawk Accipiter butleri and one Near Threatened species, Nicobar Serpent-Eagle Spilornis minimus, have been reported from this IBA site. Other Restricted Range species include Andaman Wood Pigeon Columba palumboides, Andaman Cuckoo-dove Macropygia rufipennis, Andaman Hawkowl Ninox affinis and White-headed starling Sturnus erythropygius. The Nicobar Green Imperial Pigeon Ducula aenea nicobarica which was historically very common and on some islands (“simply swarming” Butler 1899-1900), has suffered a severe decline in numbers due to hunting by airguns on Car Nicobar (Sankaran 1998). However, on Tillanchong, they were abundant. Recently, Rasmussen and Anderton (in press) have recognized Ducula nicobarica as a full-fledged species. As the species is confined to the Nicobar group of islands (Ali and Ripley 1987 called it “race peculiar to the Nicobar group of islands south of the Ten Degree Channel”), it has to be added to the list of Restricted Range species of Andaman Islands prepared by Stattersfield et al. (1998). Another notable species here is the Brown Hawk Owl Ninox scutulata of which we have four subspecies in mainland India, and Ninox affinis of which we have two subspecies: N. a. affinis (Andaman Brown Hawk-Owl) and N. a. isolata (Nicobar Brown Hawk-Owl) (Ali and Ripley 1987). Grimmett et al. (1998) recognize two subspecies of Ninox scutulata: N. s. lugubris of mainland India, and N. s. obscura of Andaman and Nicobar islands. Rasmussen and Anderton (in press) have upgraded Ninox obscura to species level (Ali and Ripley 1987 have called it Hume’s Brown Hawk-Owl Ninox scutulata obscura). If this new classification is accepted, one more species has to be added to the Restricted Range list of the Andaman Islands EBA prepared by Stattersfield et al. (1998). BirdLife International (2001) has listed Nicobar Pigeon Caloenas nicobarica as Near Threatened as “relentless trapping for food, the pet trade and perhaps still their (certainly once-prized) gizzard stones seriously suppresses populations, as does clearance of small islands for plantations, and, almost certainly, the colonization of such islands by rats, cats and other alien predators”. However, Sankaran (1998) found that this species still nests in very large numbers on Batti Malv. The Andaman Red-whiskered Bulbul Pycnonotus jocosus whistleri, endemic to the Andaman Islands, was introduced by the British in the late 1800s to Camorta Islands, but now it is also found on Car Nicobar (Sankaran 1998), apparently introduced by the Nicobarese from Camorta. The Car Nicobar group is quite interesting as far as the distribution of bird subspecies is concerned. As many of these subspecies could become full species in future, some of them would have an extremely limited distribution.

OTHER KEY FAUNA: There are very few mammals on Car Nicobar: Wild Pig Sus scrofa was introduced long ago. The Nicobar Flying Fox Pteropus faunulus, is totally endemic to the Nicobar Islands, and Car Nicobar is one of its type localities (Bates and Harrison 1997). Another species of special concern to India is Blyth’s Flying Fox Pteropus melanotus melanotus which is a relatively abundant species (Bates and Harrison 1997), but the status of the subspecies needs reassessment.

The Green Sea Turtle Chelonia mydas, Dolphin Delphinus delphis and Dugong Dugong dugon are found in the surrounding seas. The aquatic life is too rich to be described in this short account.

Cantor’s Pit Viper Cryptelytrops (Trimeresurus) cantori, an endemic snake restricted to about 100 sq. km, is reported only from Car Nicobar and Camorta Islands. Similarly, the Nicobarese Bronze-backed Tree snake Dendrelaphis humayuni population is restricted to this IBA (Anon. 2001). The endangered Nicobarese Worm Lizard Dibamus nicobaricum is also reported from this site, but nothing is known about its ecology, behaviour and status.

Pressure/threats to key biodiversity
MAIN THREATS: Construction and impact of free port; Industrialization; Urbanization; Indiscriminate fishing in coral habitats; Habitat alteration by coconut plantations.

Car Nicobar was identified as a priority island for avian conservation by the IBA workshop participants. Several developmental plans are proposed for the Nicobar Islands, particularly the building of a dry dock and refueling base for international shipping in the Galathea Bay and making Great Nicobar a free port. If implemented, these projects will irrevocably damage the island ecosystem and expedite the loss of biodiversity, as the islands are much too small to sustain the impact of such activities. Alteration of the ecosystem would adversely affect and accelerate the extinction of endemic avifauna (Sankaran 1995). Free port construction in Great Nicobar may not in itself affect Car Nicobar, but increased marine traffic may (Tara Gandhi pers. comm. 2004). Car Nicobar has the highest human population density and has the largest number of settled Nicobarese. Forest cover on this island is negligible, due to which the erosion rate is high and the coastal ecosystem is under threat (Andrews and Sankaran 2002).

Acknowledgements
Key contributors: Ravi Sankaran and K. Sivakumar.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Car Nicobar (India). Downloaded from https://datazone.birdlife.org/site/factsheet/car-nicobar-iba-india on 22/11/2024.