Fish

Water temperature plays a large role in freshwater ecosystems in the Arctic and sub-Arctic. It affects the physical and biological features of rivers, like how the water interacts with the landscape and the life cycles of organisms that live in the river. For example, unseasonably warm water temperatures in Alaska’s large rivers in 2019 caused large numbers of salmon to die before they...

Ensuring the long-term sustainability of water resources requires careful stewardship of water for societal uses (i.e. municipal, agricultural, and industrial sectors) and also for the many other benefits that aquatic ecosystems provide to humans. In particular, reservoir fisheries and river ecosystems provide a range of economic, cultural, and recreational benefits. Maximizing the...

Water temperatures affect the distribution, growth potential, and productivity of stream fishes that are targeted in subsistence, sport, and commercial fisheries across Alaska, making stream and lake temperature data critical for managing freshwater resources. Evaluating the variation in temperatures across Alaska will improve understanding of impacts of both climate change and...

Freshwater is a critical driver for island ecosystems and essential part of the water cycle in tropical islands, which is threaten by climate change. Changes in streamflow patterns may impact streams, estuarine, and coastal habitats. In Hawai‘i, these habitats support five native stream fish species. To examine how changes in streamflow have impacted habitat quality for these native...

There are significant investments by states and resource agencies in the northeast U.S. for invasive aquatic species monitoring and management. These investments in jurisdictional waters help maintain their use for drinking, industry, and recreation. It is essential to understand the risks from invasive species, because once established, species can be costly to society and difficult or...

High latitude northern ecosystems are currently warming twice as fast as the global average. Over the last several decades, this has caused dramatic losses of frozen area in the Arctic and sub-Arctic. However, it is unclear how melting coastal mountain glaciers, thawing permafrost, and declines in snowpack will affect the quality of freshwater habitat for culturally and economically...

State and federal agencies are negotiating long-term water-supply agreements for the Colorado River basin, but current policies prioritize water supply over ecological factors due to limited knowledge about how water storage strategies impact ecosystems. Researchers supported by this Southwest CASC project will develop a tool to evaluate river ecosystem outcomes of various patterns of...

Salmon are an important resource to the ecosystems, economy, and culture of the Kenai Peninsula, Alaska. However, salmon are under increasing stress due to warming water temperatures and decreasing stream flow. Groundwater is a major contributor to many streams that can help maintain fish habitat during low flows and contributes cooler water that regulates stream temperatures in the warm...

Climate change is making coldwater stream fish and their habitats more vulnerable than ever. In the Midwest, warming stream temperatures threaten recreational fishing for brook trout in their native range around the Great Lakes. To ensure that brook trout populations will persist into the future, it is crucial to focus management on areas where brook trout populations are most resilient...

The Northern Glaciated Plains in the upper Midwest United States is a region where fishing generates millions of dollars a year for local and state economies. Maintaining these revenues requires the management of fish populations that are popular and accessible (e.g. boat ramps, public land access) to anglers. Fisheries throughout the world are currently undergoing unprecedented changes...

Climate change has the potential to magnify existing problems in conservation, such as invasive species and disease. This threat is particularly severe in the Klamath Basin, where the fish parasite Ceratonova shastais making national headlines for killing salmon, and invasive trout have extirpated populations of native trout. The Klamath Basin is slated for one of the largest restoration...

Lake sturgeon are a fish of strong subsistence, cultural, and spiritual importance for many Tribal nations. But lake sturgeon are especially vulnerable to climate change given their unique life history and historical mass declines. Therefore, there is a great need to incorporate Tribal perspectives on lake sturgeon shifts and information needs into adaptation planning to conserve these...