CHAPTER 8: Sustaining Biodiversity: Saving Species

biological extinction

Complete disappearance of a species from the earth. It happens when a species cannot adapt and successfully reproduce under new environmental conditions or when a species evolves into one or more new species.

background extinction rate

natural rate of extinction

Extiction rates

Percentage or number of species that go extinct within a certain period of time such as a year.

Endangered species

Wild species with so few individual survivors that the species could soon become extinct in all or most of its natural range.

Ex. Red Wolf.

threatened species

Wild species that is still abundant in its natural range but is likely to become endangered because of a decline in numbers.

Ex. African Elephants.

HIPPCO

• Habitat destruction.

• Invasive species

• Population growth

• Pollution

• Climate change.

• Overexplotation.

Habitad fragmentation

Breakup of a habitat into smaller pieces, usually as a result of human activities.

bioaccumulation

An increase in the concentration of a chemical in specific organs or tissues at a level higher than would normally be expected.

biomagnification

Increase in concentration of DDT, PCBs, and other slowly degradable, fat-soluble chemicals in organisms at successively higher trophic levels of a food chain or web.

ESA

Endangered Species Act

• identify and protect endangered species in the US and abroad

CITES

Convention on International Trade in Endengerd Species

• Has helped reduce the international trade of mant threatened spcies.

CBD

Convention on Biological Diversity.

• legally commits participating governments to reducing the global rate of biodiversity loss and to sharing the benefits from the use of the world’s genetic resources. It also aims to prevent or control the spread of ecologically harmful invasive species.

USFWS

U. S Fish and Wildfire Services.

• primary federal agency dedicated to conserving, protecting, and enhancing fish, wildlife, plants, and their habitats for the American public

Seed banks

A conservation tool that enables the long-term storage of seeds from different plant species to preserve their genetic diversity.

Zoos

preserve some individuals of critically endangered animal species.

• The long-term goal is to reintroduce such species into protected wild habitats.

2 techniques for preserving endangered terrestrial species

• Egg pulling

• captive breeding

Egg pulling

involves collecting eggs laid in the wild by critically endangered bird species and then hatching them in zoos or research centers.

Captive Breeding

aim of reintroducing their offspring into the wild

Case Study ─ The Passenger Pigeon

• Once one of the world’s most abundant birds

• Hunted to extinction by 1900

Burmese Python

• Sold as pets

• Reproduce rapidly

• Huge appetites

• Invasive species

Habitat degradation.

Lowering the quality of a habitat through HIPPCO

Habitad destruction

the process by which natural habitats are rendered incapable of supporting their native species, driven primarily by human activities like agriculture, deforestation, and urbanization

Instric Value

the inherent worth of nature, ecosystems, and species, independent of their utility, economic benefit, or value to human beings