Bighorns Shun Desert Water Tanks

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Bighorns Shun Desert Water Tanks

Controversial Artificial Impoundments Failing Their Purpose

Tucson, AZ — Remote cameras installed to detect bighorn sheep use at two controversial man-made water developments constructed in the Kofa Wilderness in 2007 suggest the tanks have completely failed to provide water for bighorns. The cameras, installed by the US Fish and Wildlife Service (USFWS) at the McPherson and Yaqui Tanks, captured photos of mule deer, hawks, doves, vultures, coyotes and bobcats, but not a single bighorn drinking from the tanks in the two years since their construction.

“Building these artificial water developments in an attempt to artificially inflate bighorn sheep numbers was contrary to preserving the area as wilderness,” stated George Nickas, Executive Director of Wilderness Watch. “We’ve felt all along that the project was wrong from both a legal and ecological standpoint. The camera data bear that out and they completely undermine the USFWS’ argument that the tanks are necessary in Wilderness.”

A coalition of local and national conservation groups, including Wilderness Watch, the Sierra Club, and the Arizona Wilderness Coalition, filed a lawsuit in June 2007 after learning the USFWS had constructed one 13,000-gallon tank within the Kofa Wilderness and was planning to install a second. In 2008, the District Court in Phoenix ruled in favor of the USFWS. The conservation groups have appealed that decision to the U.S. Court of Appeals for the Ninth Circuit.

“The agencies have failed to demonstrate that, despite many years of constructing artificial water catchments, these catchments do anything to help the bighorn sheep,” said Sandy Bahr, Chapter Director for the Sierra Club’s Grand Canyon Chapter. “They violated the laws that protect wilderness and provide for transparency in the public process all to build tanks that the sheep don’t use. We want to ensure that both the federal and state agencies are taking actions that have had public review and comment opportunity and that are truly in the best interest of wildlife, wilderness, and the greater public.”

The Arizona Game and Fish Department’s (AGFD) McPherson Tank Habitat Enhancement and Wildlife Management Proposal lists species to benefit as: bighorn sheep 90% and mule deer 10%. AGFD’s website also lists both the McPherson Tank and the Yaqui Tank in a table of “waters considered to be critical to bighorn sheep, based on their locations in sheep habitat and documentation of sheep use from waterhole counts, aerial surveys, and remote cameras.” The data, however, clearly fail to support the Department and Service’s claims.

“Bighorn avoidance of these tanks is part of a disturbing failure of Arizona Game and Fish and the US Fish and Wildlife Service to understand critical needs of bighorn on the Kofa National Wildlife Refuge,” said ecologist Daniel Patterson, Southwest Director of Public Employees for Environmental Responsibility. Patterson is also an Arizona hunter.

“These waterholes were clearly constructed for desert mule deer as any wildlife biologist or hunter familiar with bighorn habitat would understand a priori,” stated retired Kofa biologist Ron Kearns. “McPherson Tank—especially—will artificially inflate mule deer populations that will likely compete for limited forage and finite freestanding water resources where their extensive home ranges overlap with the more restrictive ranges of Kofa bighorn. Importantly, this waterhole could help extend the home ranges and increase densities of mountain lions, while serving as a localized ‘prey trap’ for all predators.”

Congress designated the nearly 550,000-acre Kofa Wilderness in 1990. The Wilderness comprises more than 80 percent of the Kofa National Wildlife Refuge, established by President Franklin D. Roosevelt in 1939 as the Kofa Game Range.

Following a decline in the desert bighorn sheep population in 2006, the US Fish & Wildlife Service (USFWS) issued a Categorical Exclusion (CE) under the National Environmental Policy Act (NEPA) to construct the tanks. The agency provided no public notice of—or opportunity to comment on—the CE or the decision to construct the tanks. AGFD and the Yuma Valley Rod and Gun Club partnered with the USFWS in the building the tanks.

The conservation groups are asking the U.S. Court of Appeals for the Ninth Circuit to find that construction of the tanks violated the Wilderness Act by harming the area’s wilderness character and violating the Act’s prohibition on structures, installations and the use of motor vehicles. The groups also allege the USFWS violated NEPA by failing to give public notice of, or prepare a public analysis of, the environmental impacts of building the two tanks. The lawsuit asks the court to reverse the district court’s decision, vacate the USFWS decision to build the water development structures, and order their removal by non-mechanized means.

Wilderness Watch obtained the camera data through two Freedom of Information Act (FOIA) requests. The data included more than 650 photos taken at the McPherson Tank between October 2007 and July 2009 and more than 3,500 images taken at the Yaqui Tank from March through July 2009.


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