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Paddlefish Study Project

Paddlefish (Polyodon spathula) have been lost from four states and Canada, and 11 of 22 states within the remaining species range now list the paddlefish as endangered, threatened, or a species of special concern. Restoration of paddlefish populations is a shared goal of many state and federal agencies. UMESC scientists, in collaboration with the More...

  • Image of a Paddlefish (Polyodon spathula)

Near-Shore Habitat Use by Endangered Juvenile Suckers

The objectives of this study are 1) to determine how and when juvenile suckers use near-shore habitat with emergent vegetation, 2) determine how the distribution and abundance of juvenile suckers varies between near shore and offshore areas as well as between different areas of the lake over time, 3) determine if water quality conditions affect More...

  • Juvenile sucker captured in emergent vegetation.

Rescuing the Razorback Sucker

The razorback sucker (Xyrauchen texanus) is a fish few people recognize. Once abundant in the turbulent and unpredictable Colorado River, the razorback sucker is now restricted to a few remnant populations, the largest being found in Lake Mohave, Arizona-Nevada. Habitat loss due to channelization and reservoir construction, along with competition More...

  • Image of the razorback sucker (Xyrauchen texanus)

Beulah Reservoir (2001) - Food-Based Studies for Bull Trout

Bull trout were listed by the U.S. Fish and Wildlife Service as a threatened species throughout the Columbia and Klamath river basins in 1998, and Oregon has listed the North Fork Malheur River population "Of Special Concern". Reasons for the decline of bull trout in the Malheur River likely include habitat degradation, habitat fragmentation, and More...

  • Catch and release of bull trout at Beulah Reservoir.

American Fisheries Society Imperiled Freshwater and Diadromous Fishes of North America

This website provides access to the list of imperiled freshwater and diadromous fishes of North America as determined by the 2008 American Fisheries Society (AFS) Endangered Species Committee (ESC) on Fishes. At this website, one can view lists of imperiled fishes by freshwater ecoregion, by state or province boundary, and plot distributions of More...

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Silent Streams? Escalating Endangerment for North American Freshwater Fish: Nearly 40 Percent Now At-Risk

Nearly 40 percent of fish species in North American streams, rivers and lakes are now in jeopardy, according to the most detailed evaluation of the conservation status of freshwater fishes in the last 20 years. The 700 fishes now listed represent a staggering 92 percent increase over the 364 listed as "imperiled" in the previous 1989 study More...

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Evaluate Status of Coastal Cutthroat Trout in the Columbia River Basin Above Bonneville Dam

The goal of this project is to provide vital information on the current status of cutthroat trout (Oncorhynchus clarkii) populations as a necessary prerequisite to determining need and type of future recovery efforts. Coastal cutthroat trout were petitioned for listing under the Endangered Species Act in 1997.

  • cutthroat trout (Oncorhynchus clarkii)

Water Quality and Other Environmental Variables Associated With Variations in Population Densitites of the Santa Ana Sucker

The Santa Ana sucker (Catostomus santaanae), was recently identified by the U.S. Fish and Wildlife Service (FWS) as a species of special concern. This sucker is endemic to the Los Angeles, San Gabriel, and Santa Ana river drainages of southern California. The purpose of this study was to develop a better understanding of environmental factors More...

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