Search By:

Global


Administrative Units

India

Ecological Units

Biodiversity Hotspots

Bio-geographic Zones

Eco-regions

Coastal & Marine Eco-systems

wetlands

Conservation Units

World Natural Heritage Sites


Biosphere Reserves


Tiger Conservation Units

Project Tiger


Project Elephant


Important Bird Areas

Ramsar Sites

Madagascar and the Indian Ocean Islands Hotspot

The Madagascar and the Indian Ocean Islands group is unique in that despite being located close to the African continent, the biodiversity of the region is strikingly different from the African mainland. Spread over an area of 600,461 sq km the hotspot is a striking example of species evolution in isolation. Natural vegetation consists of tropical rainforests, dry deciduous forests and spiny desert.

The hotspot has 13,000 plant, 155 mammal, 310 bird, 384 reptile, 230 amphibian and 164 freshwater fish species. The hallmark of the hotspot is, however, the high level of species endemism. As much as 89.2% of plants found in the region are endemic. Interesting trees on the island include members of the baobab family like the giant Grandidier's baobab (Adansonia grandidieri) and the traveler's tree (Ravenala madagascariensis), both of which are pollinated by lemurs. Birds of Madagascar have faced severe threats leading to a number of extinctions; famous among these are the dodo (Raphus cucullatus) and the flightless elephant bird (Aepyornis maximus). Endangered birds include the Madagascar serpent-eagle (Eutriorchis astur) and the Madagascar red owl (Tyto soumagnei).

Nearly 92.9% of mammals are endemic with new species being discovered at a rapid rate. Flagship mammals are the lemurs making this hotspot the world leader in primate endemism. Of the 72 species of lemurs in the region, a striking lemur found here is Madame Berthe's mouse lemur (Microcebus berthae) which is the world's smallest primate weighing only 30 gms. Other interesting mammals found on the islands include, the fossa (Cryptoprocta ferox), the giant jumping rat (Hypogeomys antimena) and Madagascar flying fox (Pteropus rufus). With a 95.6% reptile endemism the hotspot is best known for the Seychelles' Aldabra giant tortoise (Geochelone gigantean). Amphibian endemism is at 99.9% and one of the most striking specimens is the tomato frog (Dyscophus antongili)

The world's largest terrestrial invertebrate the coconut or robber crab Birgus latro, the world's largest millipede (Sechelleptus seychellarum) and the endemic giant tenebrionid beetle (Polposipus herculeanus) are found here. Species of invertebrates on the islands include 651 snail, 40 scorpion, 459 spider, 181 dragonfly and damselfly, 211 tiger beetle, 148 scarab beetle, 300 butterfly, six freshwater crayfish and 26 freshwater shrimp species.

Over the years the hotspot and its biodiversity has been affected by human activity like agriculture, timber production, plantations, mining, hunting and grazing. Introduction of alien species like pigs, deer, rabbits, rats, cats and mongoose, and water hyacinth (Eichhornia crassipes) have affected the ecosystems drastically. About 16,131 sq km of land area in is under some form of official protection.

[The information has been sourced from the Conservation International website on biodiversity hotspots (www.biodiversityhotspots.org). Accessed in February 2008.]

ATREE, Tel: 91-80-23530069, 91-80-23533942