Andaman & Nicobar Islands’ Rich Faunal Diversity

A recent publication by the Zoological Survey of India (ZSI) titled Faunal Diversity of Biogeographic Zones: Islands of India, has for the first time come up with a database of all faunal species found on the Andaman and Nicobar (A&N) islands.

• According to the publication, A&N islands which comprise only 0.25% of India’s geographical area, are home to more than 10% of the country’s fauna species.
• The presence of a large number of species in such a small area makes the A&N islands one of the richest ecosystems and biodiversity hotspots in India.
• A long period of isolation from the mainland made the islands hotspots for speciation (the formation of new and distinct species) resulting in hundreds of endemic species and subspecies.

Faunal Diversity

• Major endemic faunal species found only on the A&N Islands and nowhere else are Narcondam hornbill, Nicobar megapode (a bird that builds nests on the ground); Nicobar treeshrew (a small mole-like mammal), Long-tailed Nicobar macaque, and the Andaman day gecko.
• Among marine fauna found on the islands, the Dugong (sea cow), and the Indo-Pacific humpback dolphin are classified as Vulnerable under the IUCN (International Union for Conservation of Nature) Red List of Threatened Species.
• Among the terrestrial mammalian species found, three species have been categorised as Critically Endangered under IUCN Red List — Andaman shrew (Crocidura andamanensis), Jenkin’s shrew (C. jenkinsi) and Nicobar shrew (C. nicobarica).
• Another unique feature of the islands’ ecosystem is its marine faunal diversity, which includes coral reefs and its associated fauna.
• More than 500 species of scleractinian corals (hard or stony corals) are found in the island ecosystem which have been protected under Schedule I of the Wildlife Protection Act, 1972.

Key Findings: Causes & Consequences

• Anthropogenic threats-tourism, illegal construction and mining are posing a threat to the islands’ biodiversity, which is already vulnerable to volatile climatic factors.
• The development paradigm that is being pushed such as tourism, construction and development of military, is not taking in account three factors — ecological fragility of the area (the endemism), geological volatility (earthquakes and tsunamis), and the impact they will have on local communities.
• Any stress can have a long-lasting impact on the A&N islands’ biodiversity, devastating the population size of any endemic fauna, followed by extinction within a limited span of time.