Date: Feb. 6, 2002

Contacts: Bill Kearney, Media Relations Officer
Andrea Durham, Media Relations Assistant
(202) 334-2138; e-mail <>

Higher Water Levels Not Scientifically Justified
To Protect Fish in Klamath Lake and River

WASHINGTON -- Current scientific evidence does not support the need to require higher water levels in Oregon's Upper Klamath Lake or higher flows on the nearby Klamath River, as proposed by two federal agencies to protect endangered and threatened species of fish, says a new interim report from the National Academies' National Research Council. The lower minimum water levels proposed by a third federal agency also lack sufficient scientific backing.

"The available scientific evidence does not support current proposals to change water levels or river flows to promote the welfare of the fish currently at risk, although future research may justify doing so," said William M. Lewis Jr., chair of the committee that wrote the report, and professor and director, Center for Limnology, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder.

Both the U.S. Fish and Wildlife Service and the National Marine Fisheries Service issued what are known as "biological opinions" last year, calling for water levels and flow rates to be increased to protect short nose and Lost River suckers, two fish species listed as endangered in 1988, as well as coho salmon, which were designated as threatened in 1997. Suckers live primarily in Upper Klamath Lake while the salmon live in both the Klamath River and the Pacific Ocean, where the river empties after running through northern California.

The agencies' opinions and accompanying water-management proposals said more water was needed than had been proposed in an earlier assessment by the U.S. Bureau of Reclamation, whose operation of dams on the river and its tributaries determines water levels. The bureau has a legal obligation to provide water to local farms, but the U.S. Department of the Interior -- of which the bureau and the Fish and Wildlife Service are part -- decided that, given the requirements of the federal Endangered Species Act, biological opinions must prevail over the bureau's assessment, even though these would result in more water being diverted from farms. However, a severe drought in the Klamath region last summer caused tempers to flare even further between farmers, whose crops were dying, and those government officials and groups supporting higher water levels in the lake and river for the sake of the endangered and threatened fish populations. This prompted the Interior Department to ask the Research Council to review the scientific validity of the biological opinions.

The committee's interim report finds no clear connection between water levels in Upper Klamath Lake and conditions that are adverse to suckers. For example, fish kills in the lake have not been linked to years of low water levels. Chemical conditions that pose a threat to suckers have not coincided with low-water years, either. In fact, the highest recorded increase in the number of adult suckers occurred in a year when water levels were low.

Based on these findings, the committee said there is no scientific basis for the Fish and Wildlife Service's proposal to keep the water at levels greater than the average high between 1990 and 2000. At the same time, however, it concluded that there also is no sound scientific support for letting the lake waters drop below mean minimum levels that occurred during the same 10-year period, which would be allowed under the Bureau of Reclamation's proposal. The risk to suckers at levels below the mean minimum occurring in recent years has not been documented.

Likewise, the committee said there is no scientific justification for increased minimum flows in the Klamath River to protect coho salmon, as called for by the National Marine Fisheries Service. The water needed to increase flows during dry years would have to come from reservoirs, but the temperature of reservoir water during the warmest months could equal or exceed those lethal to coho. The main river already is excessively warm and any juvenile coho living there probably tolerate the temperature only by staying in pockets of cool water created by ground-water seepage or small tributary flows. Adding substantial amounts of warm water could reduce the size of these thermal shelters. Tributary conditions, in fact, appear to be the critical factor governing the welfare of coho, but these conditions are not addressed in the National Marine Fisheries Service plan because Klamath dam operations do not affect them.

The National Marine Fisheries Service -- part of the U.S. Department of Commerce -- proposed the higher flows primarily to increase habitat space for coho in the main river. But the space increase that can be achieved in dry years through adjustments in dam operations is small and possibly insignificant, the committee said.

On the other hand, the reduction in minimum river flows that the Bureau of Reclamation's proposal would allow cannot be justified on scientific grounds either, the committee said. Again, as is the case with suckers in Upper Klamath Lake, the risk presented by such minimum flows to the coho is unknown since there is no documentation of how they would be affected.

The committee's final report on the environmental requirements of suckers and coho salmon is expected next spring.

The study is sponsored by the U.S. Department of the Interior and U.S. Department of Commerce. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter. A committee roster follows.

The report Scientific Evaluation of Biological Opinions on Endangered and Threatened Fishes of the Klamath River Basin is available for free on the Internet at Copies will soon be available for purchase from the National Academy Press; tel. (202) 334-3313 or 1-800-624-6242. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above).

Division on Earth and Life Studies
Board on Environmental Studies and Toxicology

Committee on Endangered and Threatened Fishes in the Klamath River Basin

William M. Lewis Jr. (chair)
Professor and Director
Center for Limnology
Cooperative Institute for Research in Environmental
University of Colorado

Richard M. Adams
Professor of Agriculture and Resource Economics
Oregon State University

Ellis B. Cowling *
Distinguished Professor
North Carolina State University

Gene S. Helfman
Institute of Ecology
University of Georgia

Charles D. D. Howard
Founder and Past President
Howard & Associates Ltd. (retired)
Victoria, British Columbia

Robert J. Huggett
Professor Emeritus of Marine Science
College of William and Mary, and,
Professor of Zoology and Vice President for
Research and Graduate Studies
Michigan State University
East Lansing

Nancy E. Langston
Environmental Studies/Forest Ecology and
University of Wisconsin

Jeffrey F. Mount
Professor of Geology
University of California

Peter B. Moyle
Department of Wildlife, Fish, and Conservation
University of California

Tammy J. Newcomb
Assistant Professor of Fisheries and Wildlife Sciences
Virginia Polytechnic Institute and State University

Michael L. Pace
Assistant Director
Institute for Ecosystem Studies
Milbrook, N.Y.

J.B. Ruhl
Professor of Law
Florida State University


Suzanne Van Drunick
Study Director

* Member, National Academy of Sciences