Chapter 18 Environmental Science Notes

unit 6 ch 18 The loth mass extinction extinction: when there are no longer any of the species in the world. •we are currently losing approximately 50,000   species per year Genetic Diversity: •scientists want to conserve genetic diversity so that the species can 'survive environmental change and inbreeding will not occur. •In   breeding occurs when individuals with similar genotypes, generally relatives, breed with each other. Categories of endangerment extinct→   no known species exist today threatened → species with a high risk of extinction in the future near threatened → species that are likely to become threatened in the future least concern → species are wide spread and abundant birds mammals amphibiavis HIPCO Habitat loss Invasive species Pollution Climate change Overharvesting Habitat loss For most species the greatest cause of decline and extinction is habitat loss. Most habitat loss is due to human development.   Invasive species Alien species (exotic species) species that live outside their historical range. Invasive species when alien species spread rapidly across large areas. Kudzu, zebra mussel, silver carp   Pollution: Threats to biodiversity can come from toxic contaminants such as pesticides, heavy metals, acids, and oil spills.   Climate change The concern is now climate change will affect temperature and precipitation around the world, and how this will impact biodiversity.   Overharvesting When individuals of a species are removed at a rate faster than the population can replace them. Dodo, American bison, passenger pigeon.   Lacey Act: one of the earliest laws in the U.S. to control the trade of wildlife first passed in 1900, the act prohibited the transport of legally harvested game animals, primarily birds and mammals, across state lines. CITES: CITES Convention on International Trade in Endangered Species of Wild Fauna and Flora developed in 1973 to control the international trade of threatened plants and animals today, CITES is an international agreement between 175 countries of the world. Red List: the (IUCN) keeps a list of threatened species. known as the Red List each country has its own way to monitor and regulate the import and export of animals on the list Conservation legislation marine mammal protection act prohibits the killing of all marine mammals in the U.S. and prohibits the import or export of any marine mammal body parts. Endangered Species Act endangered species act first passed in 1973, it authorizes the U.S. Fish and Wildlife Service to determine which species can be listed as threatened or endangered. and prohibits the hawking of these species trading these species is also illegal the act also authorizes the government to, purchase habitat that is critical to the species   Convention on biological diversity in 1992, nations came together and made a treaty to protect biodiversity. the treaty has 3 objectives conserve biodiversity sustainably use biodiversity equitably share the benefits that emerge from the commercial use of genetic resources such as pharmaceutical drugs.     steps, snappy and connections when designing and managing protected areas we must consider how close to another area they should be, how large the area is, and the amount of edge habitat the area contains communities come together, typically forming an abrupt transition   edge: the area where 2 different ecosystems meet, typically forming an abrupt transition like a grassy field meeting a forest Biosphere reserves: protected areas consisting of zones that vary in the amount of permissible human impact.