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Significant Portion of Its Range

The U.S. Fish and Wildlife Service and National Oceanic and Atmospheric Administration's National Marine Fisheries Service (the Services) jointly announced a policy to improve and clarify implementation of the Endangered Species Act (ESA) by providing a formal interpretation of the phrase "significant portion of its range" that appears in the ESA definitions of "endangered species" and "threatened species." This policy improves ESA implementation by providing a consistent and uniform standard for interpretation of the phrase "significant portion of its range" by the Services in making decisions to list species in need of federal protection and delist species no longer in need of federal protection.


Karner blue butterfly.
 

This policy clarifies that the Services can list a species if it is endangered or threatened in a "significant portion of its range," even if that species is not endangered or threatened throughout all of its range. Under the policy, a portion of the range of a species is defined as "significant" if the species is not currently endangered or threatened throughout all of its range, but the portion's contribution to the viability of the species is so important that, without the members in that portion, the species would be in danger of extinction, or likely to become so in the foreseeable future, throughout all of its range.



View the News Release
View the Final Policy
View the Federal Register notice
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Last updated: March 31, 2015