Unformatted text preview: Species Prone to Extinction Species Prone to Extinction Low reproductive rate Specialized niche Narrow distribution Fixed migratory patterns Rare Commercially Valuable Require large territories Factors Leading to Decline in Factors Leading to Decline in Species Environmental Stress Large Environmental Disturbance Extreme Environmental Conditions Resource Limitations Invasive nonnative species Geographic Isolation Mass Extinction Mass Extinction loss of a significant number of species in short period of time, lack of speciation to replace them 5 mass extinctions in history where 50% of animal species were wiped out All related to some form of climate change Mass Extinction Mass Extinction
CretaceousTertiary Extinction 65 MYA 16% Marine families, 47% marine Genera, 18% Land vertebrates, including the dinosaurs caused by asteroid End of the Triassic 199210 MYA 52% Marine Genera Volcanic Activity, formation of Atlantic Ocean Mass Extinction Mass Extinction PermianTriassic Extinction 251 MYA 95% of all Species possibly asteroid impact Late Devonian 364 MYA 57% Marine Genera cause unknown OrdovicianSilurian extinction 439 MYA 50% Marine Genera, caused by decline in sea levels due to glaciation Protecting Biodiversity Protecting Biodiversity Legal Aspects Do we have a responsibility to protect and control nature? Who “owns” nature? Do we have a right to exploit natural resources at the expense of diversity? Domestic Laws to Protect Wildlife Domestic Laws to Protect Wildlife Lacey Act of 1900 Prohibits the transport of Live or dead Wild Animals across state Borders without a permit Endangered Species Act of 1973 Endangered Species Act Endangered Species Act Threatened and Endangered Species identified By US Fish and Wildlife, National Marine Fisheries Service Species can not be hunted, injured, collected or killed in the United States Decisions based on Biology only, though economic considerations taken into account when deciding recovery plans Between 1973 and 2002 number of species increased from 921250 59% plants 41% animals Estimate is that 30,000 species are in danger Critical habitats and recovery plans established by the department of Interior 124 established as of 2002 USFWS and NMFS come up with recovery plans75% of species have recovery plans 1982 Interior can establish Habitat Conservation Plans Landowners can destroy some critical habitat or kill endangered species in exchange for taking protective steps Relocation of species, set aside preserves, pay govt. to buy habitat elsewhere Weaknesses Weaknesses Evasive techniques can be used by landowners land can be managed to reduce use by endangered species planting crops, plowing fields, deforestation No timetable for establishment of recovery plans International Treaties International Treaties 1975 Convention on International Trade in Endangered Species (CITES) lists species that cannot be traded as live specimens because endangered Enforcement difficult Small fines Member countries can exempt themselves Convention on Biological Diversity (1992) binds signatory nations to reverse global decline in biodiversity Sets guidelines for compensation, regulation of bioprospecting Sanctuary Approach Sanctuary Approach National Wildlife Refuge System 524 refuges in the USA 20% of endangered species and their habitats Potential Use for abandoned military bases Zoos, Parks Seed Banks, Gene Banks Wildlife Management Wildlife Management Regulation of fishing and hunting to manage populations Manipulation of Vegetation and Water Supplies ...
View Full Document
- Fall '08
- Rare species, extinction mass extinction, Mass Extinction Mass