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Module 4:
Biomes of the World
(Part-III)
Biodiversity Hotspots
http://coralreef.noaa.gov/aboutcorals/values/biodiversity/resources/coraltri_bur
dick.jpg
Diversity rich areas in the world
Tropical rain forests
Coral reefs
Large tropical lakes…fishes…isolated
productive habitat
Deep sea…..age and stability
Tropical shrublands
Tropical grasslands
Deserts
Temperate shrublands
Diversity rich areas in the world
Marine systems contain 28 of 33 existing
animal phyla
13 of these phyla are present only in
marine environment
Biodiversity Hotspots
Biodiversity hotspots
The 34 biodiversity hotspots contain:
• at least 150,000 plant species as
endemics, 50 percent of the world’s
total.
• 29 percent of the world's freshwater fish
species
In only 2.3 percent of the planet's land area
What are these hotspots?
Qualifying factors for hotspot designation:
1. Regions harbouring a great diversity of endemic
species
– Must have at least 1,500 endemic species (0.5% of
the global total)
2. Significantly impacted and influenced by human
activities
– Must have lost at least 70% of its original habitat
Why hotspots rich in endemism?
1. Isolation over long period of geologic time
– Island
2. Benign environments
– Tropical and Mediterranean
3. Topographically diverse
– Mountains
Benign environments +
varied topography +
isolated for long geological time
Presence of species not present anywhere else
Why hotspots rich in endemism?
Isolation of hotspots:
1. Tropical island archepelagos
– Caribbean island
– Philippines
2. Large island
– Caledonia
3. Combination of both
– Sundaland
4. Continental islands
– Isolation by surrounded deserts, mountains, seas
– Indo-Burma, Western Ghats
5. Landlocked islands
Threats to hotspots
1. Fragile ecosystems
2. Loss of habitat:
1. Physical restriction of species
2. No other population of the same species…..global
extinction
3. Species not prepared to compete with the exotics
Hottest of the hotspots
1. Madagascar & Indian Ocean Islands
2. Philippines
3. Sundaland
4. Atlantic Forest
5. Caribbean
6. Indo-Burma
7. Western Ghats & Sri Lanka
8. Eastern Arc Mountains & Coastal Forests
Hotspot
Endemic
plants
Endemics as a
Percentage
of World Total
Madagascar & Indian
Ocean Islands
11,600
3.9
6,091
2
15,000
5
2948
1
11,700
3.9
Indo-Burma
7,000
2.3
Western Ghats & Sri
Lanka
3,049
1
Himalayas
3,160
1.1
Philippines
Tropical Andes
Southwest Australia
Mediterranean Basin
References
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Campbell, N.A. 1996. Biology, 4th Edition. The Benjamin/Cummings Publishing
Company, Inc., Menlo Park, California. http://www.worldbiomes.com/
Large Marine Ecosystems of the World
http://www.lme.noaa.gov/LMEWeb/downloads/lme64.pdf
Ecoregions of the World by WWF
http://www.worldwildlife.org/science/ecoregions/item1847.html
Hotspots in Context
http://www.conservation.org/where/priority_areas/hotspots/Pages/hotspots_in_conte
xt.aspx
Norman Myers, Russell A. Mittermeier, Cristina G. Mittermeier, Gustavo A. B. da
Fonseca & Jennifer Ken. 2000. Biodiversity hotspots for conservation priorities.
NATURE | VOL 403 | 24 FEBRUARY 2000.
Roberts, et al. 2002. Marine biodiversity hotspots and conservation priorities for
tropical reefs. Science 295, 1280-1284
Maps and resources:
http://staff.tuhsd.k12.az.us/gfoster/standard/7seas.gif
World Atlas on Biodiversity http://archive.org/details/worldatlasofbiod02groo
World Mangrove Atlas http://archive.org/details/worldmangroveatl97spal
Food for Thought
-Which aspects of the biodiversity hotspot concept
do you consider the most relevant for the
conservation of marine and coastal sites?
- Do you see any risk involved in using this concept
for prioritizing conservation at global and national
level?
- Some areas harbor higher species richness than
others – why is that so? Do you see ways of
enhancing species richness in threatened or
degraded areas?
A difficult decision: imagine you were responsible for the
management of your site: would you rather invest the restricted
funds available in the maintenance / restoration of singular
habitats and endemic species, or would you concentrate on
broader conservation and outreach strategies? Think about your
reasons – and potential strategies for covering both aspects.