Rivers and Streams

Freshwater ecosystems support the health and well-being of human life and society through a myriad of services. Intact freshwater biodiversity maintains the health of freshwater ecosystems and the benefits they provide. However, staggering rates of freshwater biodiversity loss and declining ecological function of freshwater ecosystems threaten these natural benefits and human life. This...

Nearshore marine ecosystems in Alaska and Hawai‘i rely heavily on organic materials and nutrients delivered by rivers and streams. It is hypothesized that the magnitude and timing of stream flows influences this delivery of materials to coastal ecosystems. However, despite previous research on the topic, there is still considerable uncertainty about how stream flow may influence these...

Manoomin, or wild rice, is an essential, sacred species for Native people throughout the Upper Great Lakes region, who have relied on the plant for food and ceremony for hundreds of years. Manoomin is also important to non-Native people, who also harvest it and benefit from the wildlife sustained by it. Manoomin is an indicator of ecosystem health—if manoomin is healthy so is the...

Freshwater is a critical driver for island ecosystems. Climate change has fundamentally altered the water cycle in tropical islands. The changes in dynamic patterns of streamflow could result in the temporal and spatial difference in the riverine, estuarine, and coastal habitats that support native species. In particular, these habitats support the nine native aquatic species in Hawaiʻi...

Stream fish are in peril from a changing climate, particularly for species with restricted distributions or populations on the southern edge of their range. For these fish, the opportunity to escape warming temperatures is limited by the network of stream channels accessible to them. To deal with temperatures beyond their physical capacity, fishes must move, adapt, or die. However...

Aquatic invasive species threaten our lakes, streams, and wetlands. These species not only change the biology within the waterbody, but they can change the way we use those waterbodies and the resources they produce. Those changes may have large economic impacts, such as direct management costs and indirect costs to fisheries, tourism and commerce. These species can be small like zebra...

In the Gulf of Alaska, streams will experience more dramatic low water events, interspersed with larger and potentially more frequent high flow events in the coming decades. Reduced stream flows are likely to occur due to diminished snowpack and seasonal droughts, while higher flow events are likely to occur with more frequent storms and rain-on-snow events. These changes are likely to...

Cold-water adapted Brook Trout were historically widely distributed – ranging from northern Quebec to Georgia, and from the Atlantic Ocean to Manitoba in the north, and along the Appalachian ridge in the south. However, studies show that due to factors associated with climate change, such as increased stream temperature and changing water flow, the number of streams containing Brook...

The Science Issue and Relevance: Coastal wetlands are some of the most productive and valuable habitats in the world. Louisiana contains 40% of the United States’ coastal wetlands, which provide critical habitat for waterfowl and fisheries, as well as many other benefits, such as storm surge protection for coastal communities. In terms of ecosystem services, biological resource...

Freshwater mussels are an important component of freshwater ecosystems. They can filter a large amount of water, affecting both water clarity and water chemistry. Their shells provide physical habitat for other organisms, they re-direct necessary nutrients to the bottom of the water column, and their excreted material can enhance the growth of algae and macroinvertebrates. However...

Climate change is likely to impact erosion rates, the magnitude and frequency of extreme rainfall/mass wasting events, and the accumulation of sediment in coastal areas. However, long-term rates of erosion and sediment delivery to coastal systems are poorly constrained and there is limited understanding of the relative effects of climate change versus land-use change on these processes

Overview A changing regional climate in the northeastern US has significant implications for the fundamental bioenergetics of fish species, with implications for their population resilience and their ability to provide critical ecosystem services, with particularly important implications for tribal communities. For example, warming soil and water temperatures may increase the...