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Chapter VII
Biodiversity Hotspots
and Conservation
Priorities
Why conservation efforts should be
prioritized to certain zones
A living fossil: Gymnocrinus richeri
The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
Introduction Chapter VII:
Biodiversity Hotspot and Conservation Priorities
Despite that biodiversity losses are occurring everywhere on
Earth, some areas which are both extraordinarily rich in life
forms and particularly threatened from a number of sources
have been identified.
The principal behind the concept of biodiversity hotspot
comes from the fact that despite that all ecosystems on
Earth should be preserved, only limited funds are available
worldwide to undertake such needed actions.
As a general trend, equatorial and tropical zones have a
particularly rich biodiversity when compared to the rest of
the word. The colder it gets, the less bio-diverse the
ecosystems tend to be.
As such, it is necessary, in order to preserve as much
biodiversity as possible, to focus on areas which are the
most at risk and where the efforts will result in the greatest
number of species saved.
Examples of biodiversity hotspots include the rainforest of
Borneo and as a matter of fact most of the forests of
Indonesia and Malaysia, Reef environments across tropical
zones and many others.
Often, loss of biodiversity arise from rapid deterioration of
the environment in the pursue of the extraction of
resources for immediate profit. One must however
understand that such models are not sustainable.
18 principal biodiversity hotspots where conservation should
be prioritized have been identified.
Once extinct, species have disappeared forever from the
planet.
© Sylvain Richer de Forges
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.1 (a) What is a
Biodiversity Hotspot?
A biodiversity hotspot is a biogeographic region with a
significant reservoir of biodiversity that is threatened
with destruction.
The concept of biodiversity hotspots was originated by
Dr. Norman Myers. The hotspots idea was also
promoted by Russell Mittermeier in the popular book
“Hotspots Revisited” (2004).
To qualify as a biodiversity hotspot on Myers 2000
edition of the hotspot-map, a region must meet two
strict criteria: it must contain at least 0.5% or 1,500
species of vascular plants as endemics, and it has to
have lost at least 70% of its primary vegetation.
Around the world, at least 25 areas qualify under this
definition, with nine others possible candidates. These
sites support nearly 60% of the world's plant, bird,
mammal, reptile, and amphibian species, with a very
high share of endemic species.
© Sylvain Richer de Forges
2010 © Sylvain Richer de Forges. All rights reserved.
149
The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
Source: Conservation International
VII.1 (b)
The above map shows the principal biodiversity hotspots which have been identified around the world. The above map
shows that most biodiversity rich regions are in tropical and subtropical areas. South East Asia has numerous hotspots.
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.2 Case Study:
Madagascar
Madagascar, is the fourth-largest island in the world,
and is home to 5% of the world's plant and animal
species, of which more than 80% are endemic.
Emblematic species includes the lemur, the
carnivorous fossa, three bird families and six baobab
species.
Madagascar's long isolation from the neighboring
continents has resulted in a unique mix of plants and
animals, many found nowhere else in the world.
Of the10,000 known plants native to Madagascar, 90%
are found nowhere else in the world.
Madagascar's varied fauna and flora are endangered
by human activity, as a third of its native vegetation
has disappeared since the 1970s, and only 18%
remains intact. Since the arrival of humans 2000
years ago, Madagascar has lost more than 90% of its
original forest.
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.3 (a) Case Study:
Philippines
The Philippines is one of the ten most biologically megadiverse countries and is at or near the top in terms of
biodiversity per unit area. Around 1,100 land vertebrate
species can be found in the Philippines including over 100
mammal species and 170 bird species not thought to exist
elsewhere.
With an estimated 13,500 plant species in the country, 3,200
of which are unique to the islands, Philippine rainforests
boast an array of flora, including many rare types of orchids
and Rafflesia. Philippine territorial waters encompass as
much as 1.67 million square kilometers producing unique and
diverse marine life and is an important part of the Coral
Triangle.
Deforestation, often the result of illegal logging, is an acute
problem in the Philippines. Forest cover declined from 70%
of the country's total land area in 1900 to about 18.3% in
1999. Many species are endangered and scientists say that
South East Asia, which the Philippines is part of, faces a
catastrophic extinction rate. According to Conservation
International, the country is one of the few nations that is,
in its entirety, both a hotspot and a megadiversity
country, placing it among the top priority hotspots for
global conservation.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.3 (b)
The Philippines is suffering from severe degradation of its biodiversity. Most of this occurs as a result
of deforestation, trading of animal species and overexploitation of resources
© Sylvain Richer de Forges
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.4 Case Study:
Borneo
Borneo is very rich in biodiversity compared
to many other areas. There are about
15,000 species of flowering plants with
3,000 species of trees, 221 species of
terrestrial mammals and 420 species of
resident birds in Borneo. It is also the
centre of evolution and radiation of many
endemic species of plants and animals. The
remaining Borneo rainforest is the only
natural habitat for the endangered Bornean
Orang-outang. It is also an important refuge
for many endemic forest species, as the
Asian Elephant, the Sumatran Rhinoceros,
the Bornean Clouded Leopard, and the
Dayak Fruit Bat.
It is one of the most biodiverse places on
earth. The World Wildlife Fund has stated
that 361 animal and plant species have
been discovered in Borneo since 1996,
underscoring its unparalleled biodiversity.
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.5 (a) Case Study:
Barrier Reefs
The Australian Great Barrier Reef is the world's largest
coral reef system composed of over 2,900 individual reefs and 900
islands stretching for over 2,600 kilometres over an area of
approximately 344,400 square kilometres. The reef is located in the
Coral Sea, off the coast of Queensland in north-east Australia.
The Great Barrier Reef supports a diversity of life, including
many vulnerable or endangered species, some of which are
endemic to the reef system.
The Great Barrier Reef has been classified as one of the great
wonders of the world and is therefore a focus of attention. However,
most reef ecosystems around the world and especially in the South
Pacific are extremely rich in biodiversity.
Such ecosystems are at risk from overexploitation, pollution and
climate change.
The loss of coral reefs would result in enormous biodiversity loss and
potential destabilization of entire marine ecosystems. The
preservation of coral reefs should be a high priority along with forest
ecosystems to preserve the biodiversity of life on Earth.
© Sylvain Richer de Forges
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII 5 (b)
Coral reefs are amongst the most biodiverse ecosystems on Earth, yet some of the
most threatened.
Barrier reefs around the world
contain an incredible amount
of biodiversity of which most
remains unknown to date.
As we know that these
ecosystems will be greatly
affected by climate change and
anthropic disturbances across
the century and will suffer
from
massive
biodiversity
losses, efforts to study their
biodiversity
should
be
intensified while we still can.
© Sylvain Richer de Forges
2010 © Sylvain Richer de Forges. All rights reserved.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
VII.6 Case Study:
The Galapagos
The Galapagos islands are an archipelago located on
the equator in the eastern Pacific ocean. They are
composed of about 40 islands of volcanic origin. On
these islands can be found the National Park of the
Galapagos and a marine reserve which has been
classified as a UNESCO world heritage site.
In 1835 Charles Darwin studied its species diversity
which inspire his famous study on evolution and
natural selection in 1859.
The islands are very rich in flora and fauna. The
archipelago inhabits 58 species of birds among 28 are
endemic and unique reptiles such as the iguana and
giant turtles. The marine fauna is also very rich with
over 300 species of fish and small mammals.
The islands hold a variety of plant species which vary
in accordance to different microclimates. Of the 875
known plant species, 228 are endemic.
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The Diversity Of Life On Earth
Chapter VII: Biodiversity Hotspots and Conservation Priorities
Conclusion Chapter VII
As highlighted in this chapter, because some
areas are much richer in biodiversity than
others; some are more threatened and
resources for conservation efforts are limited,
the concept of biodiversity hotspots has been
introduced.
At least 18 such zones have been classified as
biodiversity hotspots of which most of South
East Asia and would therefore require much
conservation efforts. However, all of these
zones, despite their classification are still
experiencing serious environmental pressures.
If we are to succeed in preserving the
biodiversity of life on Earth, our efforts should
focus on these hotspots as a start.
However, such efforts need to be done in
parallel to global negotiation issues such as
climate change and trade of illegal timber if
significant benefits are to remain in the long
term.
Conservation is
international issue.
both
a
local
and
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2010 © Sylvain Richer de Forges. All rights reserved.
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