40 CFR § 257.3-2 - Endangered species.
(a) Facilities or practices shall not cause or contribute to the taking of any endangered or threatened species of plants, fish, or wildlife.
(c) As used in this section:
(1) Endangered or threatened species means any species listed as such pursuant to section 4 of the Endangered Species Act.
(2) Destruction or adverse modification means a direct or indirect alteration of critical habitat which appreciably diminishes the likelihood of the survival and recovery of threatened or endangered species using that habitat.
(3) Taking means harassing, harming, pursuing, hunting, wounding, killing, trapping, capturing, or collecting or attempting to engage in such conduct.