๐ฆ Chapter 02 ยท Topic 02 ยท Biodiversity Hotspots
Biodiversity Hotspots โ India’s 4 Hotspots
Norman Myers criteria, India’s four biodiversity hotspots, endemic species, and their conservation significance for UPSC & PSC exams.
What is a Biodiversity Hotspot?
The concept of a Biodiversity Hotspot was introduced by British ecologist Norman Myers in 1988. A hotspot is a biogeographic region that is both a significant reservoir of biodiversity and is threatened with destruction.
To qualify as a hotspot, a region must meet two strict criteria:
- Must contain at least 1,500 endemic vascular plant species (โฅ 0.5% of world’s total)
- Must have lost at least 70% of its original habitat (i.e., only 30% or less remains)
โก Key Numbers: There are 36 biodiversity hotspots globally (as per Conservation International’s latest count). They cover only ~2.5% of Earth’s land surface but contain more than 50% of the world’s endemic plant species and ~43% of endemic bird, mammal, reptile, and amphibian species.
๐ฟ India’s Position: India has 4 biodiversity hotspots โ the highest number among South Asian nations. This reflects India’s extraordinary biological wealth concentrated in specific threatened regions.
India’s 4 Biodiversity Hotspots
1. Western Ghats & Sri Lanka
- Location: Western coast of India (Kerala, Karnataka, Tamil Nadu, Goa, Maharashtra) + Sri Lanka
- Area: ~189,611 kmยฒ (original extent); only ~6.8% primary vegetation remains
- Key endemic flora: Cullenia exarillata, Myristica swamps, Dipterocarpus indicus
- Key endemic fauna: Lion-tailed macaque, Nilgiri tahr, Malabar giant squirrel, Nilgiri langur, Purple frog (Nasikabatrachus sahyadrensis)
- UNESCO World Heritage Site: Western Ghats declared WHS in 2012
- Receives heavy monsoon rainfall; one of world’s 8 “hottest hotspots”
2. Himalayas (Eastern Himalayas)
- Location: Extends across Nepal, Bhutan, NE India, and parts of southern Tibet and Yunnan (China)
- Key endemic flora: Rhododendrons (over 30 endemic species), orchids, medicinal plants
- Key endemic fauna: Snow leopard, red panda, Himalayan brown bear, takin, golden langur
- Contains the world’s highest altitude ecosystems โ alpine meadows, glaciers, high-altitude wetlands
- Threatened by climate change, hydropower projects, and overgrazing
3. Indo-Burma (Indochina)
- Location: Covers Myanmar, Thailand, Laos, Cambodia, Vietnam, and parts of NE India (Manipur, Mizoram, Nagaland)
- Known for: Exceptional freshwater biodiversity โ one of the world’s richest freshwater fish regions (Mekong River basin)
- Key endemic fauna: Irrawaddy dolphin, saola (Asian unicorn), Indochinese tiger, giant Mekong catfish
- NE India’s contribution: High endemism in plants, birds, and herpetofauna
- Threatened by deforestation, dam construction, and wildlife trade
4. Sundaland
- Location: Malay Peninsula, Sumatra, Borneo, Java, Bali + India’s Nicobar Islands
- Key endemic flora: Rafflesia (world’s largest flower), Dipterocarp forests
- Key endemic fauna: Orangutan, Sumatran tiger, Sumatran rhino, proboscis monkey
- India’s Nicobar Islands are part of this hotspot โ home to Nicobar megapode, Nicobar pigeon
- Severely threatened by palm oil plantations and logging
Hotspots at a Glance โ Comparison Table
| Hotspot | Indian States/UTs | Key Endemic Species | Primary Threat |
|---|---|---|---|
| Western Ghats & Sri Lanka | Kerala, Karnataka, TN, Goa, Maharashtra | Lion-tailed macaque, Nilgiri tahr, Purple frog | Deforestation, plantations |
| Himalayas (Eastern) | Sikkim, Arunachal, Uttarakhand, HP | Snow leopard, Red panda, Golden langur | Climate change, hydropower |
| Indo-Burma | Manipur, Mizoram, Nagaland, Assam | Hoolock gibbon, Sangai deer | Deforestation, wildlife trade |
| Sundaland | Nicobar Islands (A&N UT) | Nicobar megapode, Nicobar pigeon | Tsunamis, development |
Why Hotspots Matter
- Conservation priority: Limited resources must be directed where biodiversity loss is most acute
- Maximum species per unit area: Hotspots offer the best return on conservation investment
- Endemism concentration: Species found nowhere else on Earth โ once lost, gone forever
- Ecosystem services: Hotspots provide water, climate regulation, and livelihoods to millions
- Indicator of global health: Hotspot degradation signals broader planetary biodiversity crisis
โก Note on Andaman Islands: The Andaman Islands are NOT part of any biodiversity hotspot. Only the Nicobar Islands fall within the Sundaland hotspot. This is a common exam trap.
India’s Contribution to Global Biodiversity
- 4 of 36 global hotspots = ~11% of all hotspots within Indian territory
- India hosts 3 of the world’s 34 “hottest hotspots” (Western Ghats is among the top 8)
- India’s hotspots together cover about 5% of India’s land area but contain disproportionately high biodiversity
- Sacred groves, community reserves, and traditional conservation practices supplement formal hotspot protection
Revision Checklist
โ
Hotspot concept: Norman Myers, 1988
โ Two criteria: โฅ1500 endemic vascular plants AND โฅ70% habitat lost
โ 36 hotspots globally (Conservation International)
โ India has 4 hotspots: Western Ghats & Sri Lanka, Himalayas, Indo-Burma, Sundaland
โ Western Ghats: Lion-tailed macaque, Nilgiri tahr, Purple frog; UNESCO WHS 2012
โ Himalayas: Snow leopard, Red panda, Golden langur
โ Indo-Burma: Freshwater biodiversity, Hoolock gibbon, Sangai deer
โ Sundaland: Nicobar Islands (NOT Andaman); Nicobar megapode
โ Hotspots cover ~2.5% land but hold 50%+ endemic plant species
โ Andaman Islands โ hotspot; only Nicobar Islands = Sundaland hotspot
โ Two criteria: โฅ1500 endemic vascular plants AND โฅ70% habitat lost
โ 36 hotspots globally (Conservation International)
โ India has 4 hotspots: Western Ghats & Sri Lanka, Himalayas, Indo-Burma, Sundaland
โ Western Ghats: Lion-tailed macaque, Nilgiri tahr, Purple frog; UNESCO WHS 2012
โ Himalayas: Snow leopard, Red panda, Golden langur
โ Indo-Burma: Freshwater biodiversity, Hoolock gibbon, Sangai deer
โ Sundaland: Nicobar Islands (NOT Andaman); Nicobar megapode
โ Hotspots cover ~2.5% land but hold 50%+ endemic plant species
โ Andaman Islands โ hotspot; only Nicobar Islands = Sundaland hotspot