Year of compilation: 2004
AVIFAUNA: Narcondam Island has the distinction of being the sole area of distribution of the Narcondam Hornbill. This hornbill has one of the smallest natural ranges of any bird species in the world (BirdLife International 2001). Thus it a high priority species for conservation. Hussain (1984) estimated a population of more than 400 birds, while Ravi Sankaran estimated the total to be around 330-360 birds. However, based on systematic line transect methods, Yahya and Zarri (2002a) estimated 432 birds, with an approximate density of 72 birds/sq. km. Flocks of up to 50 birds have also been reported congregating on fruiting figs on this island (Yahya and Zarri 2002a). Vijayan and Sankaran (2000) found that the hornbills were not distributed evenly. Higher densities were seen along the ridge that bisects the island and low densities were seen in the northern part of the island. This could be due to differences in availability of fruiting trees during the study area. Details of ecology and behaviour are given by Hussain (1984), Vijayan and Sankaran (2000) and Yahya and Zarri (2002a). The Andaman Scops Owl Otus balli is the other globally Threatened and Restricted Range bird species present on the island. Yahya and Zarri (2000b) recorded 22 species during their one month survey, including a sighting of 11 Fairy Terns Gygis alba. A specimen collected over a hundred years ago in the Bay of Bengal is the only record of this bird within Indian limits (Ali and Ripley 1987).
OTHER KEY FAUNA: As Narcondam is a tiny volcanic island, not connected to land mass, terrestrial mammalian fauna is absent. However, Nicobar Flying Fox Pteropus faunulus and Narcondam Small Flying Fox Pteropus hypomelanus are the most common mammals on this island. Among reptiles, Andaman Dwarf Gecko Cnemaspis kandiana, widely distributed in Andaman and Malay Archipelago, is also found on Narcondam Island. The Andaman Day Gecko Phelsuma andamanense, is also restricted in distribution to the Andaman group (Daniel 2002). The Common Amphibious Sea Snake Laticauda laticauda, confined to the Bay of Bengal and Nicobar Island, is seen here, while the Andaman Water Monitor Varanus salvator andamanensis is the only large predator on the island and is a threat to the Narcondam Hornbill, especially its young ones.
The Narcondam Hornbill is the one Threatened bird species in India that is entirely restricted to the Andaman Islands Endemic Bird Area. Constrained by the limits of its island home, its range and population size are threats in themselves. The population is constantly susceptible to stochastic events such as natural disasters. Primary threats arise from the establishment of a police outpost on the island in 1969. The police personnel introduced several pairs of goats, which by 1998 had grown to a population of 130–150 in the police camp and over 250 feral goats at large on the island, as a result of which there is very little evidence of natural regeneration of the woodland. About 50 acres of forest have been lost to the police camp and adjacent plantation of fruit trees and vegetable plots, and a little more in the environs has been degraded. At least 10–12 live trees are cut each year for fuel wood for the camp, and over 500 poles were cut to make and repair fences to prevent goats from entering the vegetable plots (Vijayan and Sankaran 2000). Regular cyclones destroy many older trees with suitable nesting cavities, and cutting of large old trees is likely to have a detrimental impact on the island’s hornbill population. Until very recently, the police staff hunted Narcondam Hornbills for meat but now this has more or less stopped. There is also a sizeable population of domestic and feral cats on the island, although whether they prey on the hornbills is not known. The complete removal of goats from the island appears to be a high priority. It has also been suggested that a second population of the Narcondam Hornbill might be established on another suitable island in the Andamans, as a backup measure in case of serious population declines or natural disasters. Before any such action is taken, an ecological appraisal of the recipient island should be undertaken to estimate which species the hornbill would compete with for nesting sites and food (BirdLife International 2001).
BirdLife International (2020) Important Bird Areas factsheet: Narcondam Island Wildlife Sanctuary. Downloaded from http://www.birdlife.org on 28/09/2020.