Many animal species are at risk of becoming extinct, or dying out. Although natural causes can be a factor, humans are largely responsible. Activities such as logging, farming, and construction have destroyed many animal habitats, and illegal hunting has only added to the problem. A group called the International Union for Conservation of Nature (IUCN) surveys different animal populations to determine if they are at risk.

critically endangered
Noun

level of conservation between "endangered" and "extinct in the wild."

Noun

organism threatened with extinction.

extinct
Adjective

no longer existing.

Noun

environment where an organism lives throughout the year or for shorter periods of time.

pesticide
Noun

natural or manufactured substance used to kill organisms that threaten agriculture or are undesirable. Pesticides can be fungicides (which kill harmful fungi), insecticides (which kill harmful insects), herbicides (which kill harmful plants), or rodenticides (which kill harmful rodents.)

poach
Verb

to hunt, trap, or fish illegally.