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USGS - science for a changing world


Daniel J Wieferich

Physical Scientist

Biogeographic Characterization

Office Phone: 303-202-4603
Fax: 303-202-4710
ORCID: 0000-0003-1554-7992

Supervisor: Sky Bristol
The United States is home to more than 3,000 fish species and over 322 million people, and they all depend on the same water. Healthy aquatic resources are vital to the integrity of the United States and essential for sustainable fish populations. Unfortunately, in many places around the United States, fish and the habitats on which they depend are degraded or in decline. Almost 40 percent of the nation’s freshwater fish species are considered at risk or vulnerable to extinction. Habitat loss is the most common cause for extinction of freshwater fish in the United States over the past century, and many saltwater fish are also in decline due to habitat degradation. In 1997, Congress declared that one of the greatest...
This item provides the ScienceBase query that identifies components of the fish habitat assessments within the Eastern Gulf of Mexico States. It also contains a link to a configuration file that pulls these pieces of information into a logical order. This information can be accessed through the ScienceBase API to display a summary of fish habitat assessment information for the Eastern Gulf of Mexico States.
Big Sauble River draining into Lake Michigan in Ludington, Michigan.
Table showing human and natural landscape factors used for the 2015 national assessment of stream fish habitat.
Tags: 2015, Hawaii, Table
The Northeastern States contain over 17,000 dams with most built before 1910 for agricultural and industrial water power uses. A few have been built more recently for flood control, recreation, water supply, and energy generation. In many cases, the dams have outlived their expected life expectancy and use, but continue to block the passage of migratory fish species, such as American Shad, river herring, American Eel, Rainbow Smelt, and Atlantic Salmon, to and from their historic upstream spawning grounds. Additionally, the fragmentation of stream systems by dams have reduced Brook Trout populations in some locations. Progress is being made on this impairment as over 67 dams were removed during 2010 to 2014 in...
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