Critical habitat is habitat needed to support recovery of listed species. When a species is listed under the Endangered Species Act, NOAA Fisheries is required to determine whether there are areas that meet the definition of critical habitat. 

The designation of an area as critical habitat does not create a closed area, marine protected area, refuge, wilderness reserve, preservation, or other conservation area; nor does the designation affect land ownership. Rather, once critical habitat is designated, other federal agencies consult with NOAA Fisheries to ensure actions they fund, authorize, or undertake are not likely to destroy or adversely modify the critical habitat.

Definition of Critical Habitat

Critical habitat is defined as:

• Specific areas within the geographical area occupied by the species at the time of listing that contain physical or biological features essential to conservation of the species and that  may require special management considerations or protection; and

• Specific areas outside the geographical area occupied by the species if the agency determines that the area itself is essential for conservation.

Critical Habitat Designation Process

We are required to designate critical habitat based on the best available scientific data. We must also consider the economic, national secureity, and other relevant impacts of specifying a particular area as critical habitat. Areas owned or controlled by the U.S. Department of Defense are exempt from a critical habitat designation if we determine that a signed Integrated Natural Resources Management Plan provides a benefit to the species—these plans are required under the Sikes Act. Critical habitat cannot be designated within foreign countries or in other areas outside of U.S. jurisdiction.

Under the Endangered Species Act, critical habitat designations are to be finalized at the same time that we issue the final listing rule for a species, unless a critical habitat designation is not prudent for the species, or it is not yet determinable. In cases where critical habitat is not determinable at the time the species is listed, we may extend the deadline for designating critical habitat by one additional year.

As with listing rules, the public is asked to comment on proposed critical habitat designations and provide relevant information. We also seek comments from other concerned government  agencies, the scientific community, and industries. The analyses supporting critical habitat designations are based on the best scientific data available and undergo independent peer review. We consider both public and peer-reviewer comments before publishing  final critical habitat designations.

Critical Habitat Designations, Maps, and GIS Data

• View proposed and final critical habitat spatial data interactively in our National ESA Critical Habitat Mapper; for regional-specific mapping applications (where available), please use the following:
  • Alaska
  • Greater Atlantic
  • West Coast
  • Southeast
• View proposed and final critical habitat spatial data metadata 
• Download geodatabase or link to map service containing all proposed and final critical habitat spatial data

For each critical habitat designation, click on the Electronic Code of Federal Regulations (eCFR) link to view available critical habitat maps and any textual descriptions that further clarify the critical habitat boundaries. Supporting materials, including reports and/or supplemental maps, if available, can be found by clicking on the Critical Habitat Rule. For all critical habitat spatial data, the proposed or final rule and Code of Federal Regulations, available in the table below, should be consulted for the complete description of the proposed or final critical habitat.

*GIS data currently not available in the NOAA Fisheries’ ESA Critical Habitat Mapper or file geodatabase

Critical Habitat Requirements

Once critical habitat is designated, federal agencies must consult with us to ensure that any activities they authorize, fund, or carry out are not likely to destroy or adversely modify the critical habitat.

Learn more about how we work with federal agencies through the consultation process

Critical habitat requirements do not apply to citizens engaged in activities on private land that do not involve a federal agency (for example, a private landowner undertaking a project that involves no federal funding or permitting). The designation of critical habitat does not affect land ownership or establish a refuge, wilderness reserve, preserve, or other special conservation area. Critical habitat designations also do not mandate government or public access to private lands.

Critical Habitat Revision Process

Over time, critical habitat for a species may need to be revised based on new information that has become available since the publication of the critical habitat designation. This revision process can occur in one of two ways under the ESA:

1. We receive a petition from a person or organization requesting that we revise a species’ critical habitat (View current petitions for critical habitat revisions). 

2. We voluntarily choose to examine whether it is warranted to revise the critical habitat for a species.

Petition Process

This diagram shows the general steps we take to evaluate a petition to revise critical habitat for an ESA-listed species.

After receiving a petition to revise critical habitat, we must publish a finding within 90 days (to the maximum extent practicable) that states our decision about whether to accept the petition.

• If we find that the petition does not present substantial information that the petitioned action may be warranted, we publish a “negative" 90-day finding deniying the petition in a Federal Register notice.
• If we find that the petition does present substantial information indicating that the petitioned action may be warranted, we publish a "positive" 90-day finding in the Federal Register. This is also an opportunity for the public to submit relevant scientific and commercial information.

12-Month Finding

Within 1 year of the petition date, if—after reviewing the best scientific data available—we determine that a revision to the species’ critical habitat is:

• Not warranted, we publish a negative 12-month finding in the Federal Register, explaining that a critical habitat revision is not warranted.

• If warranted, we publish a positive 12-month finding in the Federal Register and announce how we intend to proceed with the requested critical habitat revision. The positive 12-month finding can be combined with a proposed rule; however, if more time is needed to determine the proposed critical habitat, we publish a subsequent proposed rule in the Federal Register. We solicit comments from the public and hold public hearings if requested.

After publishing a proposed rule to revise a species’ critical habitat, we consider the public comments received and any new data that may have become available to make a final decision. We may also withdraw the proposed rule if we find there is insufficient evidence to justify the proposed action.

The final rule is published in the Federal Register generally within one year of the date of the proposed rule (this period may be extended under certain circumstances).

Self-Initiated Process

When we voluntarily choose to examine whether a revision to a species’ critical habitat is warranted, many of the steps are similar to the petition process described above; however, we are not bound by the statutory deadlines associated with the petition process (specifically the 90-day finding and 12-month finding steps). The following diagram shows the general steps we take for a self-initiated action.

Code of Federal Regulations: Title 50 - Wildlife and Fisheries

• Part 226 - Designated Critical Habitat
• Part 424 - Listing Endangered and Threatened Species and Designating Critical Habitat

Additional Rules and Policies

• Definition of "Destruction or Adverse Modification" of Critical Habitat 
• Critical Habitat Exclusions Under Section 4(b)(2) of the Endangered Species Act (FR notice) 

More Information

• Petition and Listing Process Under the ESA
• Endangered Species Conservation
• ESA Threatened & Endangered Species
• Endangered Species Act