Critical habitat

Critical habitat is a habitat area essential to the conservation of a listed species, though the area need not actually be occupied by the species at the time it is designated. This is a specific term and designation within the U.S. Endangered Species Act-ESA

Critical habitat must be designated for all threatened species and endangered species under the Endangered Species Act, with certain specified exceptions. Designations of critical habitats must be based on:

Before designating critical habitat, careful consideration must be given to the economic impacts, impacts on national security, and other relevant impacts of specifying any particular area as critical habitat. An area may be excluded from critical habitat if the benefits of exclusion outweigh the benefits of designation, unless excluding the area will result in the extinction of the species concerned.

If habitat land is nonfederal, there must be a federal connection for the ESA to be triggered; purely private actions are not covered. A federal agency with whom a landowner is dealing must ensure that its actions (which may include giving a loan, increasing irrigation flows, etc.) do not adversely modify these areas.

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