Changes to ESA Critical Habitat Designations Will Leave At-Risk Species Vulnerable

September 4, 2020

Gary Frazer
U.S. Fish and Wildlife Service
Department of the Interior
Washington, DC 20240

Samuel D. Rauch III
National Marine Fisheries Service
Office of Protected Resources
1315 East-West Highway
Silver Spring, MD 20910


Re: Endangered and Threatened Wildlife and Plants; Regulations for Listing Endangered and Threatened Species and Designating Critical Habitat; Docket Number FWS-HQ-ES-2020-0047.

Dear Mr. Frazer and Mr. Rauch:

The American Fisheries Society (AFS) respectfully submits the following comments in response to the proposed rule, Endangered and Threatened Wildlife and Plants; Regulations for Listing Endangered and Threatened Species and Designating Critical Habitat; Docket Number FWS-HQ-ES-2020-0047, published in the Federal Register on August 5, 2020.

AFS is the world’s oldest and largest professional society of fishery and aquatic scientists and managers. AFS seeks to improve the conservation and sustainability of fishery resources and aquatic ecosystems by advancing fisheries and aquatic science and promoting the development of fisheries professionals. AFS supports and promotes the use of best available science in policy-making efforts.

We appreciate the opportunity to comment on the above referenced rulemaking regarding the proposed definition of habitat under the Endangered Species Act (ESA) of 1973. Given the U.S. Supreme Court ruling in Weyerhaeuser Co. v. U.S. FWS, 139 S. Ct. 361 (2018) which requires that an area must be ‘habitat’ in order to be designated as ‘critical habitat,’ we support the concept of including a regulatory definition of habitat for the ESA.

As Congress recognized in explaining the purpose of passing the ESA, listed species depend upon ecosystems. Indeed, many ESA petitions and listings have identified the loss of useable habitat or access to habitat in ecosystems as the reasons for the decline in species. Increases in water temperature, lack of water in streams and rivers, poor water quality, invasive species, and habitat degradation have imperiled forty percent of all freshwater species. The immense challenges of climate change for fish and aquatic resources will undoubtedly lead to additional declines.

Therefore, based on the knowledge of imperiled species experts within our membership, we believe that any definition of habitat within the ESA regulations needs to be broad and flexible enough to account for a wide variety of situations to ensure that the ecosystems upon which endangered species and threatened species depend are conserved. Such situations may include a species expansion into habitats not currently utilized, through processes such as, but not limited to, colonization from source populations, response to climate change, habitat restoration, and species reintroductions.

AFS recommends that the definition of habitat take into account areas that may not ‘house’ the species but are important for flow of energy and resources. Examples of this in practice could include the karst topography that is critically important for species like the Alabama Cavefish and Ozark Cavefish, the upstream spring inputs that are important to species like Pygmy Sculpin, salmonids, springfish, and pupfish, or the headwater habitats necessary for imperiled species downstream like the Truckee River flows for the Cui-ui and Lahontan Cutthroat Trout in Pyramid Lake, NV. The breadth of a definition of habitat is important for fisheries management because conservation efforts for species protection and recovery are moving toward holistic watershed approaches (e.g., Native Fish Conservation Areas like the Little Tennessee River).

Here, we explain our concerns with the two proposed definitions. In the first definition proposed by FWS/NMFS, the statement “Habitat includes areas with existing attributes that have the capacity to support individuals of the species” is restrictive for restoring degraded or destroyed habitat, especially as the definition does not mention what habitat excludes. For example, before parts of the Ash Meadows National Wildlife Refuge were restored, those areas wouldn’t have provided existing attributes that had the capacity to support individuals. No one would argue that the human altered Ash Meadows spring seeps weren’t critically important for the pupfish, killifish, and dace endemic to that small geographic area. But, if the drained and altered springs couldn’t support those species at present, then that area could not have been included as critical habitat under this proposed definition which just ensures status quo and nothing better. That wouldn’t make sense from a management perspective for species recovery or the legislative perspective intended by Congress in enacting the ESA. Indeed, if a similar definition was used for polluted waters in the U.S. under the Clean Water Act, we would never have improved water quality by installing treatment systems to remove pollutants, as the definition leaves the only condition as status quo. Those springs were species habitat that needed to be restored to allow these species to be self-sustaining. A similar argument could be made for listed species whose habitat has been altered by dams (salmon, sturgeon, minnows, darters) and for wetland-dependent species.

In the second definition, the statement “Habitat includes areas where individuals of the species do not presently exist but have the capacity to support such individuals, only where the necessary attributes to support the species presently exist” could be restrictive to management for species that need to be moved outside of known historic ranges such as to mitigate for climate change or land use change. This definition leaves the status quo as the desired state for species conservation without any direction that many areas will need to be rehabilitated to allow reintroduction of species back into their native range. The use of the word “presently” is problematic for adaptive management under environmental change because it could be used to imply that the species had to exist in that location in the past.

The second part of the second definition is also problematic. Many species are listed because the necessary attributes to support the species do not exist in habitat that was suitable in the past and part of their historic distribution. For example, to delist the Rio Grande Silvery Minnow, populations are required in the Pecos River and the Big Bend National Park reach of the Rio Grande, which are part of its historic range. However, these reaches do not have environmental conditions at present to support the species. Though these reaches are not designated critical habitat for this species, failing to consider them habitat in a broader context does not make sense if the management goal is to delist the species which will likely need habitat rehabilitated to allow them to be self-sustaining populations. The agencies point out these restrictions in their explanation of the definition. The second definition is more restrictive than the first.

Thank you for your consideration. The fisheries professionals of AFS are available to work with you to identify a definition of habitat that does not restrict designation of critical habitat to recover and delist species. Please contact AFS Policy Director Drue Winters at [email protected] if we can provide you with additional information.


Douglas J. Austen, Ph.D.
Executive Director