Endangered Species
Ecological Services

Listing and Critical Habitat | Petition Proces
s (click here for advice on submitting a petition)

The Petition Process

Petitions are formal requests to list a species as endangered or threatened under the Endangered Species Act. The ESA requires that we make and publish specific findings on the petition. We (or the National Marine Fisheries Service for most marine species) must make a finding within 90 days of receiving a petition (to the extent practicable) as to whether or not there is “substantial information” indicating that the petitioned listing may be warranted. If this preliminary finding is positive, a status review is conducted. Within one year of receipt of the petition, we must make a further finding that the listing either is or is not warranted. A positive one-year finding can be incorporated into a proposed listing rule or, if a prompt proposal is precluded by other listing activities, the proposal may be deferred. These “warranted but precluded” determinations require subsequent one-year determinations in each successive year until either a proposed listing rule is published or a “not warranted” finding is made.

Last updated: August 30, 2016