Areas of Critical Environmental Concern (ACEC) is a conservation ecology program in the Western United States, managed by the Bureau of Land Management (BLM). The ACEC program was conceived in the 1976 Federal Lands Policy and Management Act (FLPMA), which established the first conservation ecology mandate for the BLM. The FLPMA mandate directs the BLM to protect important riparian corridors, threatened and endangered species habitats, cultural and archeological resources, as well as unique scenic landscapes that the agency assesses as in need of special management attention.

Criteria

To be considered a potential ACEC an area must meet criteria of both relevance and importance.

Relevance

An area meets the relevance criteria of an ACEC if it contains one or more of the following:

Importance

An area meets the importance criteria if it is characterized by one or more of the following:

Designated ACECs

Alaska

Arizona

California

Colorado

Idaho

Montana

(For more detailed descriptions of the following sites see)

Nevada

New Mexico

Oregon

Utah

Wyoming