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Preserving Earth’s Biological Diversity. Chapter 17. Delisted - On August 8, 2007. Species Richness. Genetic Diversity. Ecosystem Diversity. Biological Diversity. Extinction Types. Local Extinction Ecological Extinction - functionally extinct Biological Extinction - extinct
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Preserving Earth’s Biological Diversity Chapter 17 Delisted - On August 8, 2007
Species Richness Genetic Diversity Ecosystem Diversity Biological Diversity
Extinction Types • Local Extinction • Ecological Extinction - functionally extinct • Biological Extinction - extinct • Commercial Extinction
Some Stats About Species • 1.4-1.8 catalogued organisms • 5-100 million thought to exist - we don’t know! • 99.9% of all that existed are now extinct
Extinction-Level Events (ELE), • 5 recognized mass extinctions • Most famous being the dinosaurs
Continuous, slow rate of extinction over millions of years 1 every 200 years Numerous species disappear over geologically short time frame. Endangered and Extinct Species • Background Extinction vs. Mass Extinction
Endangered Species • Endangered Species Act
IUCN - The Red List International Union for Conservation of Nature and Natural Resources
Maintains smaller fish populations by eating gar Nests eventually become small islands of trees Digs underwater holes used by other aquatic organisms Gator trails clear out aquatic vegetation Why Biological Diversity Ecosystem Services and Species Richness
Endangered and Extinct Species • Earth’s Biodiversity Hotspots Small area - rich in diversity
Most wide reaching act passed by the U.S. • National Marine Fisheries Services monitors ocean species. • U.S. Fish and Wildlife Services monitors all other wildlife species. • Act forbids federal agencies to carry out, fund or authorize projects that would endanger species or their habitat. • Forbids Americans to purchase endangered species • There are 1,260 species currently on the list.
Efforts to Weaken the ESA • Make protection of endangered species on private land voluntary. • Have governments compensate landowners for their land. • Make it harder to list newly endangered species.
Efforts to Strengthen the ESA • Find out what species and ecosystem the country has. • Locate and protect the most endangered ecosystems and species within such systems. • Put more emphasis on preventing species from becoming threatened and ecosystems from becoming degraded. • Provide private landowners who agree to help protect endangered ecosystems with significant financial incentives.
CITES CITES was drafted as a result of a resolution adopted in 1963 at a meeting of members of IUCN (The World Conservation Union). 172 countries signed CITES works by subjecting international trade in specimens of selected species to a permit process.
Convention on International Trade in Endangered Species (CITES)1973 Roughly 5,000 species of animals and 28,000 species of plants are protected by CITES against over-exploitation through international trade.
Conservation Biology • Scientific study of how humans impact organisms and development of strategies to protect diversity • Wildlife management differs from conservation biology in that wildlife managers focus on game species
Conservation Biology • Protecting Habitats
Example of artic snow geese impact Wildlife Management
Benefits & Problems with Zoos • human domination over equal creatures • Some criticize their educational value as being superficial and useless. • Point to the often unnatural and controversial conditions of keeping animals in captivity • behavioral patterns such as pacing, rocking and swaying indicate suffering of animals in unsuitable enclosures.
Arabian Oryx Between October 1996 and March 1999, the numbers of Arabian Oryx in the wild in Oman fell from 400 to 100. In 3 years, poachers have removed or killed at least 200 oryx. The situation has become so precarious that 39 wild oryx have been moved to enclosures to protect them from poaching.