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Minimum Viable Population. The smallest population for a species which can be expected to survive for a long time Many factors effect MVP – the study of those factors is often called Population Viability Analysis – or Population Vulnerability Analysis – or PVA. English Skylark.
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Minimum Viable Population • The smallest population for a species which can be expected to survive for a long time • Many factors effect MVP – the study of those factors is often called Population Viability Analysis – or Population Vulnerability Analysis – or PVA
Metapopulation • A series of small, separate populations united together by dispersal • Thus even if all members of one population go extinct, other populations survive and dispersal from survivor populations can recolonize the area – a rescue effect
Population dynamics of Bay Checkerspot Butterfly
Habitat Loss Orange County, California
Habitat Loss • Habitat is the physical and biological environment used by an individual, a population or a species • Habitat degradation is the process by which habitat quality for a given species is diminished • Habitat loss occurs when the habitat quality for a given species is so low that the environment can no longer support the species
Ecosystem Loss • Ecosystem is a group of organisms and their physical environment • Ecosystem degradation occurs when alterations to an ecosystem degrade or destroy habitat for many of the species that constitute the ecosystem • Ecosystem loss occurs when the changes to an ecosystem are so great and so many species typical of that ecosystem (especially dominant species) are lost that the ecosystem switches from one type to another
Processes that degrade habitat and ecosystems • Contamination • Human built structures • Soil erosion • Changing fire regimes • Human consumption of water
Copper Basin, Tennessee 1926 1939
Restoration of Burra Burra Pit, Copper Basin Mid-1990s Mid 2000s
Copper mine tailings, Butte, Montana – largest Superfund site in America
Dying Coral Reefs Bleached coral Silted out reef
DDT in Zimbabwe
Pacific or California Fire-bellied Newt –don’t try this at home w/o washing hands
Snake migration in Shawnee Copperhead
Dingo Fence – The World’s Longest – New South Wales
Smokey the bear - 1953
Smokey the Bear - 1960