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Purposes of protected areas . protect focal sp. / spp. umbrella species protect biodiversity (spp. richness, endemism) protect large, functioning ecosystems BUT … how do we go about prioritizing?. Large-scale conservation planning. ecoregions biodiversity hotspots limitation?
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Purposes of protected areas • protect focal sp. / spp. • umbrella species • protect biodiversity (spp. richness, endemism) • protect large, functioning ecosystems BUT… how do we go about prioritizing?
Large-scale conservation planning • ecoregions • biodiversity hotspots • limitation? • inappropriate for fine-scale conservation actions (i.e. protected area selection)
GAP Analysis: Proactive, multi-species approach to identify areas of conservation priority, and inform reserve planning and management efforts. Can be done at various spatial scales. www.gap.uidaho.edu for more info Groom et al, (2006)
Population viability analysis (PVA): Method used to inform reserve system planning efforts that focus on single species that uses demographic and environmental data (including variability) to model probability of extinction. Can be based on population sizes and/or size of landscape. (Vos et al. 2001)
Reserve design issues SLOSS(Single Large or Several Small) • single large reserve should be preferred to several small reserves for nature conservation - J. Diamond 1975 • agree or disagree? • advantages / disadvantages to both approaches? vs.
Extinction Immigration Small Near Large Far Number of Species Single large • Theory of Island Biogeography: species-area curve • more spp. at equil. and w/ lower extinction rates • protect • patch interior spp. (undisturbed habitat) • high trophic level spp. • communities / ecosystems • poor dispersers • but… Rate
Several small • small reserves maximize diversity… why? • Locate areas of highest richness • issue: what are you trying to conserve? • species richness • rare spp. • taxonomic diversity • ecological / system processes • not necessarily concordant
Shape of reserve • circular is ideal to minimize edge effect • Also minimize • within reserve dispersal distances • extinction risk • interaction of size and shape • what are characteristics of focal spp./system?
Principles of reserve design Generally Worse Generally Better degree of protection size fragmentation number
Generally Worse Generally Better Connectivity -corridors Connectivity - stepping stones Habitat diversity shape
Generally Worse Generally Better reserve composition management human presence
(Soulé 1991) (Shafer 1997)
UNESCO International Biosphere Reserve model • 3 concentric zones • core • buffer • transition • 3 complementary functions • conservation • development • logistic
Must consider how various factors influencing wildlife are impacted when designing reserves as well: • Fragmentation • Climate change • Disturbance regimes • Add to this various human stakeholders and different conservation goals and you have… • A complex problem with many answers. One overarching message: • Don’t do the same thing everywhere