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Monitoring Populations of Sage-Grouse: Proceedings of a Symposium at Idaho State University Hosted by University of Idaho and Idaho State University

The greater sage-grouse (Centrocercus urophasianus) and the Gunnison sage-grouse (C. minimus) are species of concern because of their population declines and shrinking geographic distributions. Of continuing interest is the question of population abundance and trends. This publication answers the questions that deal with sage-grouse population, More...

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Monitoring black-footed ferrets during reestablishment of free-ranging populations: Discussion of alternative methods and recommended minimum standards

Although the monitoring of black-footed ferret (Mustela nigripes) populations following reintroductions has not been haphazard, several ferret recovery groups since 1994 have recommended development of uniform standards prescribing minimum methods, intensities, and frequencies of monitoring that would provide data on population size, mortality More...

  • black footed ferret publication

Sea Otter Mortality

Recent increases in the frequency and variety of infectious diseases in the southern sea otter may jeopardize the population recovery of this threatened species. This information sheet includes a list of selected publications.

  • sea otter with its head poking out of the ocean

Fisheries Investigations for Lost River and Shortnose Suckers in Upper Klamath Lake

The value of this long-term monitoring program will provide data crucial for understanding demographic and reproductive characteristics of these endangered sucker populations. This research will have wide applicability to federal, state, and tribal agencies in the basin for management and recovery efforts.

  • Biologist holding female Lost River sucker (Deltistes luxatus)

Fish Passage through Dams in Large Temperate Floodplain Rivers: An Annotated Bibliography

This report describes an electronic database containing 474 annotated citations that are relevant to fish passage through dams in large temperate floodplain rivers. The goal of this project was to survey the literature to help define the potential ecological consequences of restricted fish passage through dams in the Upper Mississippi River System More...

  • Upper Mississippi River dam

Salvaging Injured, Recently Dead, Ill, and Dying Wild, Free-Roaming Desert Tortoises (Gopherus Agassizii)

Salvage of injured, recently dead, ill, and dying desert tortoises is a very important part of recovery programs for these reptiles. Salvaged desert tortoises can provide a wealth of information about such subjects as health, disease, presence of heavy metals and other toxicants, and causes of mortality in populations. When tortoises are salvaged More...

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Bioaccumulation and Effects of PCBs on Tree Swallows Nesting along the Housatonic River, Massachusetts

Research at the Upper Midwest Environmental Center, which gathered detailed observations on tree swallow nesting success and contaminant concentrations in 1998-2000, to guide EPA and the U.S. Fish and Wildlife Service in effectively managing the risk of chemical contaminants to wildlife and the environment.

  • Warning sign near the Housatonic River

Vegetation responses to natural regulation of elk in Rocky Mountain National Park

A quasi-experimental situation exists in Rocky Mountain National Park, where elk (Cervus elaphus) populations have increased 3-fold since 1968 following their release from artificial controls within the park. Increases in elk habitat use and decreases in deer habitat use were observed. Significant increases in cover of mosses and lichens occurred More...

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Science Support for Wetland Restoration in the Napa-Sonoma Salt Ponds

Over the past 150 years, land reclamation activities have resulted in loss of significant amounts of tidal marshes (sometimes referred to as inter-tidal wetlands, the estuarine zone that is alternately flooded and exposed) in San Francisco Bay and the Sacramento-San Joaquin Delta (Bay/Delta). Recently, in an effort to halt or reverse the decline More...

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Bioaccumulation of Mercury by Fish and Fish-forage Organisms in Camp Far West Reservoir, Yuba and Placer Counties, California

Mercury contamination from historic gold mining operations is widespread in many rivers, lakes, and reservoirs on the western slopes of the Sierra Nevada. A multidisciplinary investigation by USGS is attempting to better understand mercury dynamics and to identify hot spots within Camp Far West Reservoir in order to determine if remediation More...

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Heritability of Disease Resistance and Immune Function in Chinook Salmon, with Special Emphasis on Broodstock Culling to Control Bacterial Kidney Disease

Many diseases of trout and salmon persist in our cultured fish stocks today, despite improvements in fish culture practices and years of research on vaccines and chemotherapeutants. An excellent example is bacterial kidney disease (BKD), caused by the bacterium Renibacterium salmoninarum. Infections by R. salmoninarum are considered by many to be More...

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Effects of Swimming and Exhaustive Stress in Pacific Lamprey (Lampetra tridentata)

A management decision was made in 1994 to increase survival of migrating juvenile salmon by increasing the proportion of river water and fish passed via spill at Snake and Columbia river dams. One result of this action was an increase in dissolved gas supersaturation, which can lead to gas bubble disease in fish. This disease can lead to More...

  • Image of as bubbles in gill filaments.