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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)