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Methods for Defining and Identifying Critical Habitat for Rare and Endangered Species. Jeremy VanDerWal and Lesley Lovett-Doust Dept. of Biological Sciences, University of Windsor. Two main theories: Metapopulation theory and Landscape ecology
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Methods for Defining and Identifying Critical Habitat for Rare and Endangered Species Jeremy VanDerWal and Lesley Lovett-Doust Dept. of Biological Sciences, University of Windsor
Two main theories: • Metapopulation theory and Landscape ecology • Assume landscape is binary…composed of patch and matrix
The Patch • Metapopulation ecology • Framework for understanding population dynamics in spatially structured landscapes • remains focused on species characteristics and the patch • patches may vary in size, degree of isolation, quality, etc. • often ignores the matrix
Patch-based modeling • Attempts to relate species characteristics to characteristics of the patch -- i.e. • species abundance with patch size, shape, quality… • probability of extinction/recolonization with patch size, isolation...
The Matrix • Landscape ecology • summarizes effects of landscape composition and configuration on ecological processes • landscapes can not be simply classified as patch and matrix • Matrix is composed of patches which are more or less similar to the focal patch • the matrix matters -- i.e. influences dispersal
Patch/matrix-based modeling • Relate species characteristics to characteristics of the patch AND the surrounding matrix -- i.e. • species abundance with patch size, shape, quality…AND also surrounding landuses, soil types, etc. • probability of extinction/recolonization with patch size, isolation…BUT with isolation influenced by the matrix
Opuntia humifusa • Prickly Pear Cactus • Species at Risk in Canada (COSEWIC) • only 2 populations located at Point Pelee National Park and on Pelee Island
Rules: • Within: • primary or secondary successional savannas • perimeter of PPNP (cannot be in Lake Erie) • At least: • 10m from beach • 68m from marsh* • 128m from pond* • 174m from wet meadow* • Cannot be within: • forest • on a road or trail • park infrastructure areas * except along east beach
The challenge • Binary landscape – patch / matrix • perspective of the organism • define habitat … delineate patch • Scale of influence of the matrix • different environmental factors may have influence on a species at different scales • Incorporating multiple species…
# rare species = 4 3 7 2 3 9
GARP software FOCUS software Landscape Ecology & Metapopulation Theory Additional considerations?? Hybrid model
Acknowledgements: • Lesley Lovett-Doust • Jon Lovett-Doust • Jan Ciborowski • Phil Graniero • Helen Murphy • Jeff Holland • Fellow grad students • AERC • NHIC • NSERC • OGS • My wife, Andrea, • AND my endangered species