Cloud forests and forest structure

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WALLACE RESOURCE LIBRARY
Lecture 06 – Endemism and Biodiversity
Hotspots
This is an ‘example’ of a lecture that is given to A level students as part of their
academic lecture series whilst on their expedition.
It has been produced for the exclusive use of the lecturer conducting the series
and is solely intended for educational purposes.
Most of the material comes from Operation Wallacea sources and any other
material that has been used has been credited (as far as is possible) to the
appropriate author wherever possible.
This lecture is only to be used for EDUCATIONAL purposes.
WALLACE RESOURCE LIBRARY
Lecture 06 – Endemism and Biodiversity
Hotspots
Lecture overview
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Understanding of endemism
Use of biodiversity measurements
Conservation International’s Hotspots
Wallacea
Alfred Wallace
The Wallace Line
The Lambusango Forest Reserve
Endemism
• Endemic species are only found in one specific
geographical area
• Endemism is described on varying geographic
scales
• Could be endemic to a forest patch of a few
hundred metres, a forest, or a forest biome
Endemism
• High endemism usually occurs in areas that have
been isolated for a long time, such as islands or
isolated forest fragments
• In these regions there are usually high rates of
speciation
• Areas with high levels of endemism do not
necessarily have high biodiversity levels
Measuring endemism
Degree of endemism recorded by
• Species counts - the number of endemic
species in a given area or habitat
• The percentage of endemic species present
in relation to all species in the given area
Using measures of biodiversity
• Areas with high endemism are valuable as
those species occur nowhere else on earth
• Species that are threatened, either due to
decreasing populations, habitat loss or
excessive predation are also considered
valuable
• These factors are often used as a basis to
implement conservation measures
IUCN Red List
International Union for Conservation of Nature
Nine categories:
• Extinct
• Extinct in the Wild
• Critically Endangered
• Endangered
• Vulnerable
• Near Threatened
• Least Concern
• Data Deficient
• Not evaluated
Yellow-crested cockatoo (Critically Endangered)
less than 7000 individuals remain
Which conservation organisations
do you know?
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WWF
Conservation International
Flora and Fauna International
Wildlife Conservation Society
Birdlife International
The Nature Conservancy
Biodiversity Hotspots
• Conservation International use
two factors to determine which
areas qualify as a global
biodiversity hotspot:
– Number of endemic vascular
plant species (those found
nowhere else)
– Amount of original habitat lost
Biodiversity Hotspots
Biodiversity Hotspots
• Each hotspots contains over 1,500 endemic vascular
plants species
• This represents over 0.5% of the world’s total
vascular endemic plant species
Biodiversity Hotspots
• Degree of threat was determined by the percentage of
remaining habitat within a region, with each hotspot
retaining less than 30 percent of its original natural
habitat
• Some of the hotspots have less than 10 percent of the
original natural habitat
Biodiversity Hotspots
• Overall, the 34 hotspots once covered 15.7% of
Earth’s land surface
• 86% of the hotspots’ habitat has already been
destroyed
• Intact remnants of the hotspots now only cover 2.3%
of the Earth’s land surface
• Hold at least 150,000 endemic plant species
• Contain 11,980 endemic terrestrial vertebrate
species
Biodiversity hotspots
Biodiversity Hotspot: Wallacea
Hotspot original extent (km2)
Hotspot vegetation remaining (km2)
Endemic plant species
Endemic threatened birds
Endemic threatened mammals
Endemic threatened amphibians
Extinct species
Human population density (people/ km2)
Area protected (km2)
Source: Conservation International 2006
338,494
50,774
1,500
49
44
7
3
81
24,387
Alfred Russel Wallace
• English naturalist born in 1823
• Researched the ecology and
diversity of species in South
East Asia from Borneo to
Sulawesi, Nusa Tenggara and
on to Irian Jaya
• A contemporary of Darwin
who independently and
simultaneously wrote about
evolution and the process of
natural selection
Alfred Russel Wallace
Wallace’s, Weber’s and Lydekker’s
lines
Formation of Wallacea
Migration routes between Australasia and Asia through the Wallacean islands during
the pleistocene ice age (70,000 to 40,000 years ago). Dark green signifies where land
masses became connected
Biodiversity in Wallacea
• Roughly 10,000 species vascular plants, 1,500
endemic
• Over 650 bird species, 265 endemic
• More than 220 reptile species, 100 endemic
• Nearly 50 amphibian species, 30 endemic
Biodiversity in Wallacea
• 220 mammal species, 127 endemic
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125 species of bat
25 species of rodent
12 endemic species of primate (7 macaque and 5 tarsier)
Other charismatic endemics include anoa, babirusa,
Sulawesi palm civet
• Over 300 species of freshwater fish, 75 endemic
Buton Island
• Located off the southeast coast of Sulawesi
• 4,200 km2
• Thickly forested with
axial chain of
limestone hills rising
to 1,190 metres
• Limestone karst
forest
Lambusango Forest
• 65,000ha of uninhabitated
lowland evergreen rainforest
in southern Buton
• 2 protected areas:
Lambusango Wildlife Reserve
(28,510ha) and Kakenauwe
Nature Reserve (810ha)
• Plus 35,000ha of limited
production forest
Lambusango Forest
• Last remaining
extensive and intact
forest in southern
Buton
• Area threatened by
– Illegal logging
– Forest encroachment
– Asphalt mining
Lambusango Forest
 Tree diversity maximal for Sulawesi and good
remaining forest cover
 21 new species of vertebrate discovered
 Numerous threatened species of
herpetofauna, birds and bats
 Flagship species such as the Buton macaque,
and anoa
The research we do
• Operation Wallacea conducts research in this area to
discover what is here, and to demonstrate how
biologically important the region is.
• Very poorly studied region
• More than 50% of all the herpetofauna, small
mammal and bat species recorded throughout the
whole of Sulawesi have been recorded just in the
Lambusango
• 21 new species of vertebrate have been discovered
in the area.
• This work helps to generate funding which is then
used to protect the area.
Discussion
• Recap: What is biodiversity? What is
endemism?
• How would you design a project in order to
designate limited funding to achieve
maximum conservation benefit?
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