Rivers, Streams and Lakes

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...

The greater Mississippi River Basin (MRB) is the largest river basin in North America and the fourth largest basin in the world. The MRB encompasses 24 terrestrial ecosystems, providing habitat for 100 species of mammals, reptiles, and amphibians Its floodplain supports 40% of the waterfowl and wading birds in North America, and the MRB’s rivers transport 40% of the nation’s total...

As climate change is impacting water resources and aquatic ecosystems, there is a great need for natural resource managers to assess adaptation measures in a holistic manner. This can be done by integrating model predictions of climate, hydrology, and ecosystems with observational data to better refine estimates of conditions on-the-ground; however, it can be challenging to combine these...

Stream flow is directly tied to climate, and numerous studies provide substantial evidence that climate change is a threat to future aquatic water flow processes. In the southwestern United States, mountain snow is a primary water source for streams and rivers. However, climate change is threatening the region's mountain snow, leading to reduced snowpack, earlier snowmelt, and more...

Rain-on-snow events occur when warm rain falls on an existing snowpack, causing rapid snowmelt that can lead to damaging floods, reduced spring and summer streamflow, and altered stream temperatures, with ecological, social, and economic consequences. Rain-on-snow events can result in a loss of riverine biodiversity, decreases in fisheries production, and degradation of stream habitat...

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...

In ecosystems characterized by flowing water, such as rivers and streams, the dynamics of how the water moves - how deep it is, how fast it flows, how often it floods - have direct effects on the underlying ecological communities. Yet increasingly, climate extremes like droughts and floods are disrupting fragile stream ecosystems by specifically changing their internal aquatic flows...

Understanding the paths by which water flows through the landscape is critical for providing fresh water for human use, maintaining ecosystem function, and better predicting how disturbances such as fire or drought may impact water quantity and water quality. Yet projected changes in climate, disturbances, and land use, are likely to alter hydrologic flow paths, and natural resource...

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...

Atmospheric warming is driving a shift in precipitation from snow to rain, changing precipitation intensity and seasonality, and increasing atmospheric demand for moisture in mountain river watersheds across the western United States. These changes will likely alter the timing and quantity of streamflow in rivers draining from the mountains. The Tongue River flows from the Bighorn...