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




One of the Endangered Species Act’s strongest provisions, designation of “critical habitat” is required for all domestic species listed under the Act. Critical 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, the original definition of critical habitat said it 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 the National Marine Fisheries Service — the agencies required by law to designate critical habitat — have been hesitant to protect it. Ever since the Endangered Species Act was passed in 1973, the agencies (especially the Fish and Wildlife Service) often drag their feet on designating critical habitat or even refuse to designate it altogether.

The Center is constantly working to ensure every species listed under the Act is granted critical habitat. We’ve had great success with lawsuits to pressure the Fish and Wildlife Service and the National Marine Fisheries Service to protect habitat as soon as possible after a species receives federal protection.

Critical Habitat Rules Under Threat

Likely because of its effectiveness, critical habitat has frequently come under attack. In 2019 the Trump administration passed rules exempting species threatened by climate change (or other threats not involving direct habitat destruction) from getting critical habitat at all. These regulations also raised the bar for what constitutes “adverse modification” to habitat, letting projects proceed if their impacts are deemed localized. That leaves many species vulnerable to a death by a thousand cuts. 

Still not satisfied, the Trump administration issued a new proposal in late July 2020 to severely limit the government’s ability to protect habitat that imperiled animals and plants will need to survive and recover.  

The latest in its attempt to weaken the Endangered Species Act, this proposal limits protections to habitat that could currently support the species — but would not protect areas that could be restored or safeguarded to provide additional habitat for future recovery. That would preclude protecting habitat that has been historically used by a species as well as habitat that could be important as species move in response to threats such as climate change.

Our Work Continues

We have challenged the 2019 regulations weakening critical habitat in court, will challenge the additional change proposed in 2020, and continue our fight to make sure every single listed species receives the habitat it needs to survive. If we don’t, the extinction crisis will rapidly worsen. We can’t let that happen.

Banner photo of California condors by Loren Chipman/Flickr