Endangered Species Act: U.S. Fish and Wildlife Service Lists Two Missouri Crayfish

The United States Fish and Wildlife Service (“Service”) issued a pre-Federal Register Notice publication announcing threatened specie status under the Endangered Species Act (“ESA”) for:

• Big Creek crayfish
• St. Francis River crayfish

The two crayfish species’ range include Southern Missouri.

The Service also designated critical habitat which includes:

• Approximately 1,079 river miles for the Big Creek crayfish
• 1,043 river miles for the St. Francis River crayfish

The Missouri counties referenced include:

• Iron
• Madison
• St. Francois
• Washington
• Wayne

The ESA defines a species as “threatened” if it is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range. An “endangered” species is one that is in danger of extinction throughout all or a significant portion of its range.

Section 4(a)(3) of the ESA requires that the Service designate critical habitat concurrent with listing to the maximum extent prudent or determinable.

The Big Creek crayfish is described as a small, olive-tan crayfish with blackish blotches or specks over the upper surface of pinchers, carapace, and abdomen. The length of adult individuals ranges from 1.1 to 2.2 inches.

The St. Francis River crayfish is described as a small, dark brown crayfish with blackish blotches or specks over the upper surfaces of the pinchers, carapace, and abdomen. The length of adult individuals of the St. Francis River crayfish are stated to have been observed to be similar to the adult Big Creek crayfish.

Big Creek crayfish are stated to be generally found in streams with less than 33 feet under small rocks or in shallow burrows in headwater streams and small rocky creeks in shallow depths.

St. Francis River crayfish are stated to be generally found in swiftly moving streams under rocks and boulders in small headwater streams and up to moderately large rivers. They may prefer pool/backwater areas and run macrohabitats over faster riffles.

A copy of the pre-Federal Register Notice publication can be downloaded here.