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Who lives in your stream? Rivers and streams, even small ones, are teeming with a vast number of species, including fish, aquatic invertebrates, and algae. Stream ecology is the study of those aquatic species, the way they interrelate, and their interactions with all aspects of these flowing water systems.
Pesticide transformation products are ubiquitous in small U.S. streams, reports a new study by the U.S. Geological Survey, and could be a missing piece to the toxicity puzzle for aquatic life in headwater streams.
Mixtures of organic chemicals are ubiquitous in small U.S. streams, reports a new study by the U.S. Geological Survey. In many streams the mixtures could be affecting stream organisms.
Streams are home to countless species, some of which we’re familiar with, and some less so. The aquatic organisms in streams include fish, of course, but go far beyond that. Molluscs, like clams and mussels. Amphibians, like salamanders and frogs. The larvae of many insects, like dragonflies, damselflies, and mayflies. Algae and bacteria.
Stream ecology encompasses the study of these aquatic organisms, but also the study of the riparian zone, sediment transport, the movement of energy and nutrients within the stream, and a host of other aspects of stream ecosystems. USGS National Water-Quality Program studies of stream ecology seek to:
Assess the status and trends of aquatic ecological conditions (invertebrates, fish, algae and habitat) in rivers and wadeable streams.
Relate ecological conditions to chemical stressors (such as nutrients and pesticides) and physical disturbances (such as habitat and hydrologic alterations) in the context of different environmental settings and land uses.
Enhance understanding of factors that influence the biological integrity of streams and how stream ecosystems may respond to diverse natural and human factors.
Develop key ecological indicators of aquatic health.
How Healthy Are Our Streams?
Healthy functioning stream ecosystems provide society with many benefits, including water purification, flood control, nutrient recycling, waste decomposition, fisheries, and aesthetics. Access a national assessment of the ecological health of our nation’s streams.
Water Quality and Ecology of Small Streams (RSQA)
The Regional Stream Quality Assessment (RSQA) is studying the relations between stressors (chemical and physical) and stream ecology (fish, algae, and aquatic invertebrates) at hundreds of small streams across five major regions of the United States. Users can access an online mapping tool to see scorecards that summarize stream health at each stream site and to compare water quality at small streams across a region. Users also can download data for hundreds of chemical compounds measured in streams.
Humans, just like aquatic organisms, need water, but flood control, urban infrastructure, irrigation of agriculture, and myriad other ways we manage water affect the natural flow of streams and rivers. Learn how the ways we manage land and water affects the natural patterns of streamflow and the ecosystems that depend on them.
Nutrients and Stream Ecosystems
Intensive studies by the USGS National Water Quality Program in agricultural areas provide insight into how nutrients associated with agricultural activities have affected algal and invertebrates communities in agricultural streams.
Effects of Urban Development on Stream Ecosystems
Nowhere are the environmental changes associated with urban development more evident than in urban streams. Contaminants, habitat destruction, and increasing streamflow flashiness resulting from urban development have been associated with the disruption of biological communities, particularly the loss of sensitive aquatic species. Read about a comprehensive study of effects of urban development on stream ecosystems in nine major metropolitan areas of the U.S.
Learn about USGS research related to stream ecology at the links below.
Use the links below to access data used in USGS studies of stream ecology.
Access the most recent publications on USGS research on stream ecology below. Additional USGS publications can be found at the USGS Publications Warehouse.
Below are news stories associated with this project.
Isotopes of mercury in fish can indicate the source of that mercury, reports a new study from the USGS Regional Stream Quality Assessment.