The Green River basin is the last remaining stronghold of the Colorado squawfish (Ptychocheilus lucius) and the razorback sucher (Xyrauchen texanus) in native riverine environments. It also supports populations of the humpback chub (Gila cypha) and is a recommended recovery area for the bonytail chub (Gila elegans). Flows of the Yampa River, last free-flowing river containing endangered fish habitat in the Upper Colorado River Basin, are considered critical to the maintenance of usable fish habitat of rare and endangered fishes (Figure 1) in the Green River basin (reviewed by Tyus and Karp 1989).
Population status of Kittlitz's and Marbled Murrelets and surveys for other marine bird and mammal species in the Kenai Fjords area, Alaska
The Kittlitz's murrelet (Brachyramphus brevirostris) is a rare seabird that nests in alpine terrain and generally forages near tidewater glaciers during the breeding season. More than 95% of the global population breeds in Alaska, with the remainder occurring in the Russian Far East. A global population estimate using best-available data in the early 1990s was 20,000 individuals. However, survey data from two core areas (Prince William Sound and Glacier Bay) suggest that populations have declined by 80-90% during the past 10-20 years. In response to these declines, a coalition of environmental groups petitioned the USFWS in May of 2001 to list the Kittlitz’s murrelet under the Endangered Species Act. In 2002, we...
Abundance and Run Timing of Adult Pacific Salmon in the Tuluksak River, Yukon Delta National Wildlife Refuge, Alaska, 2002
Landscape conservation cooperatives (LCCs) are conservation-science partnerships between the U.S. Fish and Wildlife Service, U.S. Geological Survey (USGS), and other federal agencies, states, tribes, NGOs, universities and stakeholders within a geographically defined area. They inform resource management decisions to address national-scale stressors-including habitat fragmentation, genetic isolation, spread of invasive species, and water scarcity-all of which are accelerated by climate change.
Abundance and Run Timing of Adult Pacific Salmon in the Tuluksak River, Yukon Delta National Wildlife Refuge, Alaska, 2001
Spawning and Seasonal Distribution of Adult Steelhead in Southcentral Alaska’s Kasilof River Watershed from 2007 to 2008
Streams across the world are highly fragmented due to the presence of in-stream barriers (e.g., dams and stream-road crossings), many of which restrict or block fish passage. Retrofitting or replacing these structures is a high priority for restoring habitat connectivity for native fishes and other aquatic organisms in the Pacific Northwest. The task of restoring habitat connectivity for problematic stream-road crossings is daunting given the many thousands of barriers that are present and the massive financial investments required. Further, the potential risks to road infrastructure from flooding, debris flows, and climate change will need to be addressed to ensure the best allocation of resources. In this study,...
Environmental Contaminants Program: To protect, improve and restore the quality of fish, wildlife and habitat resources through the identification, prevention and correction of environmental contaminant problems in Alaska. [The page provides links to the following documents:] Contaminant Studies and Technical Reports Organochlorine Analysis in Burbot (Lota lota) (pdf. 451 KB) Contaminants in Peregrine Falcon Eggs Peregrine Falcon Population Trends: Porcupine River, Alaska Contaminant Assessment: Kenai National Wildlife Refuge Kensington Mine Area: Baseline Contaminants Study Contaminant Data: Selawik Wildlife Refuge (pdf. 7,513 KB) Contaminant Data: Nowitna Wildlife Refuge (pdf. 1,971 KB) Metal Analyses at Kanuti...
Evidence of handling mortality in fall chum salmon caused by fish wheel capture on the Yukon River, Alaska
This project will provide a comprehensive synthesis of beaver recolonization science and techniques for successful reintroduction or population expansion through a thorough, in-depth, coordinated review of all North American beaver-related information, including identification of research gaps and data needs, and recommendations for project implementation. This information will be disseminated through a series of one-day workshops.
Spawning and Seasonal Distribution of Adult Steelhead in Southcentral Alaska’s Kasilof River Watershed from 2007 to 2009
Considering Multiple Futures: Scenario Planning to Address Uncertainty in Natural Resource Conservation
An Investigation of the Potential Effects of Selective Exploitation on the Demography and Productivity of Yukon River Chinook Salmon
Yukon River Chinook salmon (Oncorhynchus tshawytscha) have been targeted in large-mesh gill net fisheries for over 100 years. Recent reductions in productivity and perceptions of reduced size and earlier age at maturation have elevated concerns regarding the potential consequences of the selective exploitation of large fish. Investigations associating changes in population productivity and demography, particularly size and age composition, with overharvest and selective exploitation are common in the fisheries literature. However, most such investigations have considered long-lived species repeatedly subject to exploitation, often prior to maturation. Similar investigations concerning semelparous Pacific salmon...