FWS closer to listing Tuscon shovel nosed snake, but highlights difficulties in critical habitat determinations
73 Fed. Reg. 43905 (Tuesday, July 29, 2008)(DEPARTMENT OF THE INTERIOR; Fish and Wildlife Service; 50 CFR Part 17; Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Tucson Shovel-Nosed Snake (Chionactis occipitalis klauberi) as Threatened or Endangered with Critical Habitat; Notice of 90-day petition finding and initiation of status review)
The Tucson shovel-nosed snake is a small snake (9.84–16.73 inches long) in the family Colubridae with a shovelshaped snout, an inset lower jaw, and coloring that mimics coral snakes. Like other shovel-nosed snakes, the Tucson shovel-nosed snake uses venom to capture arthropod prey, including scorpions, and in fact, the Tucson shovel-nosed snakes may have developed a resistance to scorpion venom. Image from Pima County, AZ.
SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 90-day finding on a petition to list the Tucson shovel-nosed snake (Chionactis occipitalis klauberi) as threatened or endangered under the Endangered Species Act of 1973, as amended (Act). We find that the petition presents substantial scientific or commercial information indicating that listing the Tucson shovel-nosed snake may be warranted. Therefore, with the publication of this notice, we are initiating a status review of the subspecies, and we will issue a 12- month finding to determine if listing the subspecies is warranted. To ensure that the status review of the Tucson shovelnosed snake is comprehensive, we are soliciting scientific and commercial information regarding this subspecies. DATES: We request that information be submitted on or before September 29, 2008.
KEITHINKING: The petition demonstrates some of the difficulties present in the designation of critical habitat. Defining critical habitat necessitates the delineation of clear boundaries on a map, but nature and species needs rarely conform to such rigid geometry. In this petition, the Center for Biological Diversity (who today issued a satisifed press release) “requested that the Service consider an ‘‘intergrade zone’ between the Tucson shovel-nosed snake and the Colorado Desert shovel-nosed snake as part of the Tucson shovelnosed snake’s range. An intergrade zone is an area of overlap between the ranges of two subspecies where individuals may possess intermediate characters or traits of both subspecies.” The Service rejected the request because it “would not be consistent with current scientific practice.” However, the Service did find that (A) threats from agricultural and urban development are credible and substantial; and that (D) existing regulatory mechanisms may be inadequate to prevent the progressive decline of populations of the Tucson shovel-nosed snake and its habitat.