Transcript Copperhead
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 Metapopulations 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 Metapopulation Dynamics Bay Checkerspot Butterfly Population dynamics of Bay Checkerspot Butterfly Types of Metapopulations 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 Copper Basin, Tennessee 1926 1939 Copper Basin today Copper Basin – Superfund site Restoration of Burra Burra Pit, Copper Basin Mid-1990s Mid 2000s Copper mine tailings, Butte, Montana – largest Superfund site in America Mine tailings outskirts of Sudbury, Ontario Restoration of Sudbury Air pollution – Mexico City Extent of Acid Precipitation Rhine River Basin Healthy Coral Reef Dying Coral Reefs Bleached coral Silted out reef DDT use in 1950s DDT in Zimbabwe Thin Egg Shells from DDT Human Built Structures Pacific or California Fire-bellied Newt Pacific or California Fire-bellied Newt – don’t try this at home w/o washing hands Tilden Park, Berkeley, CA Snake migration in Shawnee Copperhead Dandelion dispersal – along roads and railroads Bonneville Dam, Columbia River, Oregon Fish Ladders The Dingo – Canis familiarus dingo Dingo Fence – The World’s Longest – New South Wales Erosion and loss of habitat on Round Island, Mauritius Smokey the bear - 1953 Smokey the Bear - 1960 Everglades Surface Water Flow