The Andaman and Nicobar archipelago is a repository of astounding biological and cultural diversity. Situated nearly 1200 km east of the Indian mainland at the juncture of the Bay of Bengal and the Andaman Sea, this tropical archipelago of more than 800 islands, islets, and rocky outcrops span nearly seven degrees of latitude (6º 45′ N – 13º 40′ N) and consitute a land area of 8249 km². Complex geological and biogeographic histories of these rifted arc-raft continental islands have led to high degrees of endemism in both the Andaman and Nicobar groups, which are a part of the Indo-Burma and Sundaland biodiversity hotspots respectively.
Still under-explored, this region currently reports 60 species of mammals (33 endemics), 214 species of birds (106 endemics), 72 species of reptiles (25 endemics), 19 species of amphibians (10 endemics), and over 2500 flowering plants (223 endemics). The beaches of these islands provide important nesting sites to four species of marine turtles, including the Leatherback turtle (Dermochelys coriacea). The coastal zones also support large tracts of mangroves forming one of India’s largest mangrove ecosystems; these habitats foster a rich assemblage of invertebrates, monitor lizards, coastal birds and saltwater crocodiles, and serve as nurseries for several species of marine fish. Coral reefs in the Islands include nearly 200 recorded coral species and support a plethora of ecologically and economically important marine biodiversity. Protection for this biodiverse region is provided under 98 designated protected areas, including nine national parks, two marine national parks and one biosphere reserve.
The Islands are home to indigenous peoples, including the Great Andamanese, the Jarawa, the Ongee, the Sentinelese, the Shompen, and the Nicobarese. Several colonization events over the last century have led to a complex social assemblage of communities. These ‘settlers’ belong to descendants of the “convicts” at the erstwhile British penal colony on the Islands, Karen settlers from Burma, the Ranchi community, the Bhatu community, and timber workers, refugees and fishing communities from the Indian mainland. The Islands now form a Union Territory of the Republic of India.
Research on the Islands’ biodiversity has its origin in colonial era expeditions of the 19th Century. Several biodiversity inventories have been carried out since then, yet most taxa apart from birds and mammals are considered to be highly under-discovered. This is reflected in the consistent rise in species descriptions over the last two decades, including reporting of apparently common and unique species (e.g., the tree toad Blythophryne beryet and more recently, the shrew Crocidura narcondamica). Biogeographic (including phylogeographic) research have been carried out for most vertebrate groups, along with some studies on community assemblages in both terrestrial and marine ecosystems. Species-centric conservation research have been carried out on marine turtles, dugongs, the edible nest-swiftlet among many others. Apart from species recovery, applied research has explored the effects of logging, biological invasions, and climate change. Long-term research monitoring of tropical forests, crocodiles, turtles, and birds are also ongoing. Given the complex social dimensions of these Islands, socio-ecological research has been increasingly given importance, particularly in relation to fisheries and post-tsunami recovery of biodiversity.
Threats and an uncertain future
The Andaman and Nicobar Islands are at the cusp of dramatic change that may severely alter the fragile ecosystem permanently. While dramatic increases in selective logging of tropical forests in the 1990s and early 2000s were temporarily restrained by a policy change implemented by the Shekhar Singh Commission, forest loss and subsequent fragmentation continue to pose a serious threat. The fast-tracking of projects in the last two years, proposing rapid development in the archipelago – both for tourism and commerce – directly threaten large swathes of intact forests, coral reefs and sea grass meadows.
Changes on land are mirrored by changes in resource extraction at sea – rising global demand for marine resources and subsidies from the State mean that the fisheries industry continues to expand across archipelago even though evidence for for trickle down benefits to local fishing communities remains to be seen. While traditional and more sustainable extraction practices like spear fishing or trochus extraction are on the decline, trawling by Indian as well as foreign boats in international waters presents a lose-lose scenario where both livelihood security of local people as well as the health and integrity of marine ecosystems are at stake.
These changing terrestrial and marine spheres of co-occurence of people and wildlife have exacerbated detrimental human-wildife interactions: the threat to human life from salt-water crocodiles remains real but their cause is unclear, and the inevitable crop-raids by Nicobar Long-tail Macaques may see a second wave of heightened conflict after the 2006 tsunami, as forests cleared for a shipping port in Great Nicobar Island may create a similar forced overlap of people and macaques competing for resources. Invasive species like the Indian bullfrog and the African Giant Snail have expanded rapidly after human introduction, even as invasive deer and feral elephant populations appear to have declined.
The insular nature of this archipelago mean that changes to ecology above and below the sea feedback directly and rapidly to impact people’s lives. Water shortages have increased in intensity each year with rising demand from mushrooming urban centres, while concomitantly, both forest cover and fish catch continues to decline.
The precarious future of the Andaman and Nicobar Islands rests heavily on planning and management that accounts for the vast coastal and forested landscapes in the region. However, a huge challenge in providing any solution is the near absence of scientific information to inform decision-making: we have barely scratched the surface in our understanding of the ecology of these terrestrial and marine ecosystems, despite its timely relevance. What is urgently required for effective management and conservation of the natural world in the archipelago is innovative ecological research that not only provides baseline information but also mechanistic insight into ecological patterns and processes in the Islands’ ecosystems.