Biology Chapter 6: Endangered Species

What is an Endangered Species?

• An endangered species is an animal or plant that is at risk of extinction, with only a few individuals left on Earth.
• Endangered species are those that are not doing well, often due to overhunting or habitat destruction.

Evaluating Endangered Species

• Endangered species assessments consider a species' population structure, life history characteristics, abundance, and threats caused by human activities.

Identification of Endangered Species

• Under the Endangered Species Act (ESA), species can be listed as endangered or threatened.
• Endangered means a species is in danger of extinction throughout its range, while threatened means it is likely to become endangered in the near future.

Criteria to Access Extinction Risk

• The five criteria to assess extinction risk include:
  • Rate of population decline
  • Geographic range
  • Small population size
  • Restricted area or small range
  • High probability of extinction in the wild

Main Cause of Endangered Species

• Habitat loss is the primary cause of higher extinction rates.
• Other causes include habitat changes, over-exploitation, introduction of non-native species, pollution, and disease spread.

Examples of Endangered Species

• Javan Rhinoceros: only around 75 individuals remaining on the island of Java, Indonesia.
• Amur Leopard: fewer than 92 individuals remaining in their natural range.

Listing Endangered Species

• Over 157,100 species are listed on the IUCN Red List, with over 44,000 species threatened with extinction.

Critically Endangered and Endangered Species

• Critically Endangered (CR): extremely high risk of extinction in the wild.
• Endangered (EN): high risk of extinction in the wild.
• Vulnerable (VU): high risk of endangerment in the wild.

Saving Endangered Animals

• Measures to save endangered animals include:
  • Reducing food waste and consumption
  • Making cities more wildlife-friendly
  • Controlling cat populations
  • Protecting forests and habitats
  • Conserving endangered species

CITES

• CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) regulates or bans international trade in endangered species.
• "Wildlife" includes all fauna and flora, and CITES addresses both legal and illegal trade.

Learn about the definition and meaning of endangered species, why animals become endangered, and more in this quiz based on Chapter 6 of your biology textbook.