loss of biodiversity is the most important in biodiversity and conservation.it is useful to reduce the activities which are responsible for extinction and endangering of living organisms.

1. • The colonisation of tropical pacific islands by human beings has
led to the extinction of more than two thousand species of native
birds.
•The IUCN Red list (2004) document the extinction of 784 species
in the last 500 that include 359 invertebrates, 338 vertebrates
and 87 plants.
•Some of the animals that have become extinct recently include:

3. STELLER’S SEA COW (Russia)

4. DODO (Mauritius)

5. THYLACINE (Australia)

6. QUAGGA (Africa)

7. Three sub-species
(BALI, JAVAN, CASPIAN)
of TIGER
BALI
JAVAN
CASPIAN

8. - More than 15,500 species worldwide are facing threat including 12
per cent of bird species, 23 per cent of all mammal species, 32 per cent
of all amphibian species and 31 percent gymnosperm species.
- Before humans appeared on Earth, there have been five episodes of
‘mass extinction’ (i.e., loss of large number of species in a short time),
and ‘ Sixth Extinction’ presently in process.
- The current rate of species extinction is 100-1,000 times faster than
the pre-human times and our activities are responsible for the faster
rate.

10. (i) Decline in plant production
(ii) Lowered resistance to environmental
perturbation.
(iii) Increased variability in ecosystem processes
like water use, pest/disease cycles, plant
productivity, etc.

11. CAUSES OF BIODIVERSITY LOSSES
• There are four major causes (called “The Evil Quartet”) of
biodiversity losses:
•Habitat loss and fragmentation,
•over exploitation,
•alien species invasions and
•co-extinction.

12. HABITAT LOSS AND FRAGMENTATION
•It is the most important cause of extinction, e.g.
•The tropical rain forests, once covering 14 per cent of the land surface of Earth,
but now they cover only 6 per cent of the land area.
•The Amazon rain forests (called the ‘lungs of the planet’) are cleared for
cultivation of soybeans or are converted into grasslands for raising beef-cattle.
•The loss of a habitat deprives many animals and plants their homes and they
face extinction.
•Degradation of many habitats by pollution threatens the survival of many
species.
•When a large habitat is broken up into fragments, the populations of mammals
and birds with migratory habits or requiring large territories are badly affected.

13. AMAZON RAIN FOREST
(Lungs of the Planet)

14. OVER –EXPLOITATION
•When ‘need’ turns to ‘greed’, it leads to over-
exploitation of natural resources; many species
become extinct, e.g.
•Steller’s sea cow, passenger pigeon, many marine fises
became extinct due to over-exploitation by humans.

15. ALIEN SPECIES INVASION
•When alien species are introduced in an area, some of them
become invasive and may cause extinction of indigenous species,
e.g.
•Introduction of Nile Perch into Lake Victoria (East Africa)
caused extinction of more than 200 species of cichlid fish in
lake.
•Invasive weed species such as Parthenium (carrot grass),
Lantana and Eichhornia (water hyacinth) causing
environmental damage and posing threat to our native species.
The illegal introduction of the African catfish (Clarians
gariepenus) for aquaculture purposes, is posing threat to the
indigenous catfishes in our rivers.

16. CILCHID FISH

17. CARROT GRASS

18. LANTANA WATER HYACINTH

19. AFRICAN CAT FISH
INDIGENOUS CAT FISH

20. CO-EXTINCTION
•When a species becomes extinct, the plant and animal
species associated with it also become extinct, e.g.
•When a host fish becomes extinct, its unique parasites also
become extinct.
•Similarly, when one partner of a co-evolved pollitator
mutualism becomes extinct, the other partner also have the
same fate.

21. BIODIVERSITY CONSERVATION
•REASONS FOR CONSERVATION OF BIODIVERSITY
•The reasons of for conservation of biodiversity can be grouped
into following three categories.
1. Narrowly utilitarian reasons
2. Broadly utilitarian
3. Ethical reasons

22. NARROWLY UTILITARIAN REASONS
• These are obvious reasons.
• Human being derive countless direct economic benefit from nature such as
(cereals, pulse, fruits), firewood, fibre, construction materials, industrial
products (tannin, lubricants, dyes, resins, perfumes) and products of
medicinal importance.
• More than 25 per cent of the drugs are derived from plants and about
25000 species of plants are used by native people as traditional medicine.
• Now more and more resources are put into bioprospecting (i.e. exploring
molecular genetic and species level diversity for products of economic
importance) to know the economic use of plants.

23. BROADLY UTILITARIAN
•Biodiversity plays a major role in many ecosystem services provided
by the nature. These include:
(a)Production of oxygen e.g. Amazon forests produce 20 per cent of
the total oxygen in the Earth atmosphere through photosynthesis.
(b) Pollination of plants (through bees, bumble bees, birds, and bats)
without which they can not give us fruits and seeds.
(c) Aesthetics pleasures of walking through tick woods, watching
spring flowers in full bloom, walking up to a bulbul’s song in the
morning etc.

24. ETHICAL REASONS
•Every species has an intrinsic value, even
if it may not be of current economic value
to us.
•We have a moral duty to care for their
well being and pass on the biological
legacy in a good order to future
generations.

25. CONSERVATION OF BIODIVERSITY
•There are two approaches for conservation of biodiversity:
(i) In –situ conservation ( on site conservation)
(ii) Ex-situ conservation ( off site conservation)
Biodiversity Conservation Strategies
In situ conservation Ex situ conservation
Biosphere
reserves
National
Parks
Wildlife
sanctuaries
Sacred
groves
Botanical
Gardens
Zoological
Parks
Seed Banks Gene
Banks

26. IN SITU CONSERVATION
•Faced with the conflict between development and conservation, many nations
find it unrealistic and economically not feasible to conserve all their biological
wealth.
•The conservationists, have identified for maximum protection certain regions
called ‘biodiversity hotspots’ with high level of species richness and high degree of
endemism (i.e., species confined to that region and not found anywhere else.)
•Out of 34 hotspots of biodiversity in the world, three are in India, i.e. Western
Ghats and Sri Lanka, Indo-Burma and Himalayas.
•Biodiversity hotspots cover less than 2 per cent of the earth’s land area, they
harbour extremely high number of species and strict protection of these hotspots
could reduce the ongoing mass extinction by almost 30 per cent.
•In India, ecologically unique and biodiversity rich regions are legally protected as:
1) Biosphere Reserves
2) National Parks
3) Wildlife Sanctuaries and
4) Sacred Groves

27. BIOSPHERE RESERVES
•These are large tracts of protected land with multiple use
preserving the genetic diversity of representative ecosystem
by protecting wildlife, traditional life styles of the tribals
and varied plant and animal genetic resources.
•India now has 14 biosphere reserves.

28. NATIONAL PARKS
•These are areas reserved for wildlife
where they are able to obtain all the
required natural resources and proper
habitats.
•Presently, India has 90 National
Parks.

30. WILDLIFE SANCTUARIES
•These are tracts of land with or without lake
where animals are protected from all types of
exploitation and habitat disturbance.
•At present, India has 448 wildlife sanctuaries.

31. SACRED GROVES
•These are tracts of forest set aside where all the trees and wildlife
within are venerated and given total protection.
•Such sacred groves are found in Khasi and Jaintia Hills in
Meghalaya; Aravali Hills of Rajasthan; Western Ghat regions of
Karnataka and Maharashtra and the Sarguja; Chanda and Bastar
area of Madhya Pradesh.
•In Meghalaya, the sacred groves are the last refuges for a large
number of rare and threatened plants.

32. SACRED GROVE
A sacred grove or sacred woods are any grove of trees of special
religious importance to a particular culture. Sacred groves feature in
various cultures throughout the world.

33. EX SITU CONSERVATION
•The threatened animals and plants are taken out from
their natural habitat and placed in special setting, where
they can be protected and given special care.
•Botanical gardens, zoological parks and wildlife safari
parks serve this purpose.
•The gametes of threatened species are preserved in viable
and fertile conditions using cryopreservation techniques.
•Commercially important plants can be kept for long
periods using tissue culture methods or in seed banks.

34. Ex situ conservation has following
disadvantages:
•Some plants do not produce fertile seeds.
•Loss of seed viability.
•Seed destruction by pests, etc.
•Poor germination rate.
•This is only useful for seed propagating plants.
•It’s a costly process.

35. INTERNATIONAL EFFORTS FOR
BIODIVERSITY CONSERVATION
THE EARTH SUMMIT
•It was the historic convention on Biological
diversity, held in Rio de Janeiro in 1992.
•It called upon all the nations to take appropriate
measures for
(i)Conservation of biodiversity, and
(ii)Sustainable utilization of the benefits of
biodiversity.

36. THE WORLD SUMMIT
•It was held in 2002 in Johannesburg, South Africa.
•190 countries pledged their commitment to achieve a
significant reduction in the current rate of biodiversity loss at
global, regional and local levels by 2010.