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Feeling Hot Hot Hot?
Hotspots as focal points of conservation and
ecological knowledge
Mary O’Connor
Christy Royer
Questions we find interesting:
• Are hotspots good conservation
targets?
• In particular, are the 25 hotspots
proposed by Myers et al. good targets?
• Do marine hotspots exist?
• Are coral reefs hotspots or simply
diverse ecosystems?
• Are marine hotspots the same as
Why discuss hotspots?
• Targets of
conservation effort and
investment
• Areas that can be
potentially useful for
increasing our
knowledge and
understanding of local
patterns of biodiversity
Definitions of hotspots:
• High endemism and high threat (Myers et al.
2000)
• Relatively high species richness (Prendergast et
al.
1993)
• High levels of rarity or endemism (Williams
1996)
• High complementarity (Araujo and Williams 2001)
• Concentrations of endangered species
(Dobson et
al. 1997)
Tour of Hotspot Literature
• Myers
hotspots’
1988, 1990:
First mentioned ‘biodiversity
• Prendergast et al. 1993: Cross-taxon congruence,
rarity and species richness
• Williams 1996: Complementary areas as alternatives to
areas of richness as hotspots.
• Reid
1998:
• Myers
hotspots
A review of hotspot definitions and their use for
conservation
et al. 2000:
to 25
Expands list of global terrestrial
Theoretical relevance of hotspots:
• Cross-taxon congruence
• Ecological transition zones
• Sampling effects
• Scale
Hotspots in Myers et al.
They
defined ‘biodiversity hotspots’ as areas ‘where
2000:
exceptional concentrations of endemic species
are undergoing exceptional loss of habitat.’
Two criteria:
1. An area must contain at least 0.5% or 1,500 of the
world’s 300,000 plant species as endemics.
2. A hotspot should have lost 70% or more of its
primary vegetation.
Myers et al. 2000:
25 global biodiversity hotspots, areas of high endemism and
threat:
Comparison: Hughes et al. and Roberts et al.
Hughes
Roberts
Central Indo-Pacific is
biodiversity hotspot
yes
yes
Cross taxon congruence in
species richnes patterns
yes
yes
Number of small range
fishes and corals
yes
yes
Cross-taxon centers of
endemism
no
yes
Congruence of species
richness and endemicity
no
yes for corals, no for
fish, snails, and
lobsters
Hotpots as conservation
priority
no
yes
Conservation recommendations of
Hughes et al. and Roberts et al.
• A ‘two pronged’ strategy for marine conservation
shifting focus from hotspots to preservation of
connectivity and genetic diversity for pandemic
species, as well as intensive protection of peripheral
areas with high endemism.
• A different ‘two pronged’ strategy to conserve
hotspots and areas of high richness not currently
classified as hotspots due to low habitat threat.
Roberts et al. 2002: Concordance in species
richness, level of threat, and concordance in range
rarity
Discussion Questions:
• Should
hotspots be primary targets for
conservation? What about other habitats?
• Which elements of the Hughes and
Roberts conservation strategies can we
recommend, and do we have additional
suggestions?
• Is the definition of hotspot used by Myers
et al. an optimal definition?
Future directions for research:
• Continue the search for indicator species
of multi-taxon richness
• Continue the search for global hotspots in
marine systems
• Quantify patterns of invertebrate diversity
• Knowledge of regional scale variation in
species richness and patterns of endemsim.
“We could go far towards safeguarding the
hotspots and thus a large proportion of all
species at risk for an average of $20 million
per hotspot per year over the next five years,
or $500 million annually. Although this is 12.5
times the annual average of the $400 million
spent on hotspots over the past decade, it is
still only twice the cost of a single Pathfinder
mission to Mars, which has been justified
largely on biodiversity grounds (the search for
extraterrestrial life).”
-Myers et al. (Nature 2000)