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CENTER for BIOLOGICAL DIVERSITY Because life is good

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For endangered species, critical habitat is the key to survival. In fact, a study by the Center found that plants and animals with this federally protected habitat are more than twice as likely to be moving toward recovery than species without it.

One of the Endangered Species Act’s greatest components, designation of critical habitat is required for all domestic species listed under the Act. Strictly defined, this habitat includes specific areas within a species’ current range that have “physical or biological features essential to the conservation of the species,” as well as areas outside the species’ current range upon a determination “that such areas are essential for the conservation of the species.” In other words, critical habitat must include all areas deemed important to a species’ survival or recovery, whether the species currently resides in those areas, historically resided in those areas, uses those areas for movement, or needs them for any other reason.

Critical habitat provides key protections for listed species by prohibiting federal agencies from permitting, funding, or carrying out actions that “adversely modify” designated areas. Designating critical habitat also provides vital information to local governments and citizens about where important habitat for endangered species is located — and why they should help conserve it.

Despite the obvious importance of critical habitat, both the U.S. Fish and Wildlife Service and National Marine Fisheries Service — the agencies required by law to designate critical habitat — have been hesitant to do so. From the time the Endangered Species Act was passed in 1973 through the mid-1990s, the agencies, particularly the Fish and Wildlife Service, routinely claimed that critical habitat was either indeterminable or not prudent. After such claims were ruled illegal by a series of court orders, the Center brought dozens of suits to force designation of critical habitat for hundreds of species that had previously been denied this habitat protection. 

Unfortunately, the bulk of these critical habitat designations fell to the Bush administration, which did its utmost to ensure that species received as little protection as possible. During Bush’s tenure, critical habitat areas were reduced by an average of 49 percent for 67 percent of all species with critical habitat to protect, resulting in the elimination of at least 63 million acres. The administration repeatedly ignored the advice of its own and outside scientists. Of 163 peer reviews of proposed critical habitats analyzed by the Center, for example, 80 called for granting species additional habitat, while only four species received it; in several cases when proposed critical habitat was at the minimum to ensure survival, the Interior Department reduced it anyway. Habitat for the endangered San Bernardino kangaroo rat, for example, was slashed by 40 percent (22,113 acres) even though four scientists said the original protected acreage must be expanded if the species is ever to recover.


The Center is actively engaged in challenging the bad critical habitat decisions made under Bush; so far, we’ve filed suit over designations for 49 species and the Obama administration has redone or agreed to redo critical habitat for 40, with talks ongoing for others. We’re also working to strengthen habitat protections for all endangered species; in March 2010, we joined 49 other groups in asking the Obama administration for a more specific regulatory definition of “adverse modification” of critical habitat — prohibited under the Endangered Species Act — in order to halt projects that destroy habitat.

Today, less than half of listed species have critical habitat — but that’s far too few. We won’t stop fighting to give all at-risk species the crucial habitat protections they need to regain their footing in the world.

Oregon silverspot butterfly photo by GaryFalxa/U.S. Fish and Wildlife Service