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Listing Program

Black Sphinx moth larvae

When the Service is formally requested (“petitioned”) to list a species as endangered or threatened under the Endangered Species Act, we must make a finding within 90 days determining whether or not there is substantial information indicating that listing may be warranted. If this preliminary finding is positive, then within one year we must determine whether or not listing is warranted. If we determine that listing is warranted, we then prepare a proposed listing. Anyone may petition the Service to have a species listed or reclassified as endangered or threatened.

  •  A species is only determined to be an endangered species or a threatened species because of any one or more of the following factors (economics or others not listed here are not permissible under the Act):

    • the present or threatened destruction, modification, or curtailment of its habitat or range;
    • overutilization for commercial, recreational, scientific, or educational purposes;
    • disease or predation;
    • the inadequacy of existing regulatory mechanisms; or
    • other natural or man-made factors affecting its continued existence.

    The Service publishes a proposed rule to list the species as endangered or threatened in the Federal Register. At this stage, all interested parties are encouraged to comment and provide additional information on the proposal and to submit statements at any public hearing that may be held.

    Within one year of publication of a listing proposal, one of three possible courses of action must be taken: 1) a final listing rule is published; 2) if the biological information then on hand does not support the listing, the proposal is withdrawn; or 3) if, at the end of one year, there is substantial disagreement within the scientific community concerning the biological appropriateness of the listing, the proposal may be extended, but only for an additional six months. After that, a decision must be made on the basis of the best scientific information available. If approved, the final listing rule generally becomes effective 30 days after publication in the Federal Register. After a species is listed, its status is reviewed at least every five years to determine if Federal protection is still warranted.


    View PIFWO Listing Database (this is an Microsoft Access file that will download to your computer if you click on the link)

    View ECOS National Database

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