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Streamflow and Endangered Species Habitat in the Lower Isleta Reach of the Middle Rio Grande

San Acacia Dam is located in a reach of the Rio Grande that has been designated as critical habitat for two endangered species, the Rio Grande silvery minnow (Hybognathus amarus) and the southwestern willow flycatcher (Empidonax traillii extimus). Presently, Rio Grande upstream from the dam is used to convey irrigation water to the Socorro main More...

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Evaluating the Role of Wetlands to Endangered Salmonids at Toppenish and Tualatin River National Wildlife Refuge

Threatened and endangered salmonids in the Pacific Northwest often use backwaters and wetlands as they migrate toward the ocean, however our understanding of the role of wetlands to juvenile salmonids is limited. The major Objective of this study was to determine whether juvenile steelhead were being tapped on the wetland during spring, and More...

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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)

Genetic population structure of the green floater (Lasmigona subviridis): Identification of management units and associated fish hosts

Freshwater bivalves, which are among the most threatened animals in North America, present significant challenges to conservation biologists that attempt to maintain ecological and evolutionary processes within and among populations. Effective management of this rare fauna is often complicated because inadequate information exists for More...

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Investigating Passage of ESA-listed Juvenile Fall Chinook Salmon at Lower Granite Dam During Winter When the Fish Bypass System is Not Operated

Fall chinook salmon (Oncorhynchus tshawytscha) in the Snake River are currently listed as threatened under the Endangered Species Act (ESA). Although fish bypass systems reduce the mortality of fish entering turbine intakes at mainstem hydroelectric dams, they are only operated during the spring, summer, and early fall during the peaks of seaward 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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Texas Gulf Coast Field Research Station

The BFRS works cooperatively with team members from CERC and with faculty and graduate students of Department of Wildlife and Fisheries Sciences at Texas A&M University in research areas represented by the branch structure of the CERC including toxicology, ecology, biochemistry and physiology, environmental chemistry, ecogeography, and information More...

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Evaluation of sampling designs to monitor populations of freshwater mussels in small- to mid-sized drainages in the northeastern ecoregion

Freshwater mussels are declining rapidly in response to habitat degradation associated with anthropogenic changes. Williams et. al. (1993) reported that 213 of the 297 recognized taxa are considered endangered, threatened, or of special concern. There is a documented need for BRD centers to provide guidance on freshwater mussel ecology in general, More...

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Landscape Analysis of Freshwater Mussels in the Upper Mississippi River Basin

Freshwater mussels are the largest group of federally listed endangered or threatened invertebrates, and their declines may signal declining riverine health. They are a renewable resource, providing significant ecological and economic benefits to the Nation. Our study uses a landscape-level approach to assess whether the distribution of mussels More...

  • butterfly mussel (Ellipsaria lineolata)

Genetic Analysis of Salmonids and Other Fishes in the Western US

As salmonid populations continue to decline in the western US, it is imperative to develop a better understanding of ecological, genetic, and biological aspects of these species. Within the broad context of the Fisheries and Aquatic Resources Program the 5-year research goals address: development of non-lethal genetic procedures for identification More...

  • Bridgecreek, a tributary of the Stehekin river.

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)