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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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Lands within the watersheds of the Great Plains streams that are not used for crops are often used for cattle grazing and hay production. Northern Plains States are one of the nation’s top producers of cattle, which outnumber people almost three to one in North Dakota. Cattle can have direct habitat impacts by trampling stream banks, which destroys beneficial vegetation and increases sedimentation and nutrient loads. Hofmann and Ries (1991) found that livestock increased sediment runoff in North Dakota streams. Schepers and Francis (1982) reported that runoff from a Nebraska cattle farm increased total phosphorus levels in runoff by 37%. In addition, cattle watering ponds, often constructed by diverting streams,...
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There are three designated megaregions in the Pacific Coast States: Southern California, with a population of 22.4 million; Northern California, with a population of 14.6 million; and Cascadia (from Vancouver, British Columbia to Eugene, Oregon), with a population of 8.4 million. These areas have enormous effects on both the inland and coastal aquatic habitats. Continual development increases areas of impervious surfaces (completely altering natural water flows and hydrology) and the amount of sewage discharge, sediments, and other pollutants associated with urbanization. Ever increasing urban water needs can be far reaching and affect systems and fish habitat far away from the urban areas. Los Angeles, which is...
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Most of Alaska has an abundance of unaltered clean fresh water habitat that maintain remarkable self-sustaining fish populations requiring water flows in the proper amount at the right time. These habitats face an increasing number of demands. New hydroelectric projects, such as the recently proposed Susitna-Watana Hydroelectric Project, and the expansion of existing projects can, if not very carefully sited and designed, increase barriers to fish migration and create adverse hydrologic and sediment effects on streams that provide critical spawning and rearing habitat for self-sustaining salmon populations. These potential barriers are not just an issue for fish but the entire ecosystem as everything from trees...
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Major cities, such as Detroit, Milwaukee, Minneapolis/St. Paul, and numerous smaller lakefront cities support a population of over 21 million people in the Upper Midwest area. Converting land to urban areas has reduced fish habitat through the filling of wetlands, altered rivers and streams to convey artificially-caused high-flow events through these areas, decreased the streams ability to meander, and has converted natural lake shorelines to bulkheads and seawalls. Many parcels of private land in the forested portions of this region: are being sold for development of subdivided vacation communities; have impoundments developed on free flowing streams to create “new” lakefront properties; and are seeing a rapid...
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Forty-three percent of the surface area of Alaska is wetlands. On a state-wide basis, less than 2 percent of all wetlands have been developed. However, in many developing areas and communities, wetlands may be the only land type available for development. In urbanized and developed areas of Alaska, such as the Anchorage Bowl, it is estimated that over half of the wetlands have been lost to transportation corridor construction, utility installation, buildings, and other development projects. Wetland loss fragments habitat and disrupts migration of fish that use wetlands as resting places on their lengthy migrations, and it is also critical rearing habitat for young salmon. Wetland loss is also linked to altered native...
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The agricultural areas of the Mountain States have created a substantial drain on the water resources of this region. Northern Montana stands out as an area of very high risk for fish habitat degradation on the few streams and rivers in the area. This threatened area is principally comprised of row crops, such as wheat, barley, and alfalfa production, and cattle farms. Other areas of high risk of habitat degradation, such as southern Idaho and northeastern Colorado, correspond to areas with a high density of row crops, typically corn and wheat, cattle farms, alfalfa and potato (particularly in Idaho) production, and rangeland. Farms and ranches dependent on irrigation require large amounts of water diverted from...
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Miami, Tampa, Orlando, and Jacksonville rank in the top 50 largest cities in the nation by area. Atlanta and New Orleans are the only other top 50 cities in the Eastern Gulf States region. These four Florida urban centers anchor what is known as the Florida Megaregion, one of eleven recognized in the United States. New Orleans and Baton Rouge are part of the Gulf Coast Megaregion. The growing urban sprawl throughout the Gulf States leads to increasing areas of impervious surface, which results in altered water flows and more urban runoff that transports high levels of nutrients and pollution to aquatic resources. For example in central Mississippi, pathogens, litter/trash, nutrients, and pesticides from increasing...
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Urban areas significantly and negatively affect aquatic habitat quality in the Mountain States. This was particularly apparent in the rapidly growing Denver/Ft. Collins, Boise, Salt Lake City, Great Falls, and Billings areas. Highway corridors along Interstates 25 and 90 in Wyoming and 76 in Colorado were implicated to be causing high to very high risk factors. In 2015, the highly urbanized I-25 corridor between Cheyenne, WY and Pueblo, CO had a population of 4.49 million people. In these cities and their surrounding suburbs, large areas of impervious surfaces (i.e. buildings, parking lots, and roads) replace natural streamside habitat, increase pollution and sedimentation, alter hydrology, and increase the demand...
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A major hub for manufacturing and transportation, the Great Lakes and their tributaries were once an easy dump site for their waste products that included organic toxins, mercury, PCBs, and dioxins. As a result of the Federal Clean Water Act (1972) most of the direct pollution discharges from known point sources have stopped, but the legacy pollutants remain because many are trapped in lake and stream sediments. Other dissolved pollutants have long residence times because less than one percent of the water in the Great Lakes exits the lake system annually. Discharge from sewage treatment systems remains a problem, particularly where stormwater and sewage systems are combined in large urban areas. The inland fish...
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A significant number of dams are located in Iowa (> 4,000), Illinois (> 1,759), Indiana (> 1,088) and Ohio (> 2,600). Dams in the Central Midwest were built to provide mechanical power for mills, hydropower, recreation, water supplies, and water retention for urban and agricultural use. Nearly all of these dams impede fish movements in the region and particularly in the Mississippi River drainage and in the watershed of lakes Erie and Michigan. Some communities are removing dams to deal with obsolete infrastructure issues and to improve water quality, flow, and stream connectivity. For example, the removal of Black Berry Creek Dam near Aurora, Illinois in 2013 opened up 32 miles of the Fox River for fish spawning...
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The southeastern states contain the rapidly growing urban centers of Atlanta, Greenville, Columbia, Charlotte, and Winston-Salem/Raleigh with suburban corridors between them. In these cities and the surrounding suburbs, large areas of impervious surfaces replace natural streamside habitat, increase pollution and sedimentation, and alter water flow (hydrology). In this 2015 assessment, land cover type was estimated to be a major risk factor for about one-third of the estuaries of the Southeastern states. The United States Department of Agriculture reports that from 1982 to 2012 over 2.6 million acres of rural land in Georgia was developed. Development in North Carolina was almost as high, while South Carolina lost...
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Runoff and other land-based pollution from large riverside cities such as Philadelphia, Pittsburgh, Wilmington, and Washington, DC, New York City, and surrounding suburban sprawl adversely affect fish habitats in the Delaware, Susquehanna, Ohio, Hudson,and Potomac River basins, as well as many smaller streams. A concentration of human population and impervious surfaces extends from northeastern New Jersey to southeastern Virginia and to the coastal areas of the Mid-Atlantic. For example, the 2015 assessment determined high degradation risk in streams along the I-95, I-81, and I-79 corridors. Urban development continues to spread, as rural land in the states of this region declined by 5.9 million acres from 1982...
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In the 1990s, urban land in Ohio, Illinois, and Indiana increased by about 10 percent. Currently, Ohio and Illinois are among the 10 most populous states in the nation, while Indiana is 16th. Over 31 million people live in these three states. Large cities such as Chicago, Indianapolis, Cincinnati, and Cleveland, as well as the suburban sprawl throughout the region, have created large areas of impervious surfaces and urban pollution near the rivers and lakes. These factors are known to degrade fish habitat by changing water flow (hydrology) and by adding excessive amounts of nutrients, pollutants and sediment into the waters in this region.
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Wheat, corn, and soybeans are some of the primary crops grown in the Northern Plains States. About 8.5 million acres, one-fourth of the state’s land area, are used to grow wheat in North Dakota. In areas of intense cultivation, streams are often channelized for irrigation, reducing their habitat value for fish as temperature, in-channel cover, and stream flow are significantly changed. In addition, watersheds dominated by row-crop agriculture discharge excess sediment and nutrients to downstream waters. Agricultural water withdrawal was also one of the most limiting disturbances identified in this assessment. A large number of groundwater wells in the Nemaha River basin in southeast Nebraska, an area dominated by...
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The northeast is one of the most urbanized areas in the country, with a high percentage of impervious surfaces in some of its watersheds. These impervious surfaces alter the water flow (hydrology) of streams and increase sedimentation, nutrient loading, and pollution in rivers, lakes, and bays. Urbanization also results in the direct loss of fish habitat as wetlands are filled, streams diverted, and channels dredged. The effects of urbanization are apparent in the greater New York City area, Boston, Westchester-Springfield, Providence, and Buffalo-Rochester. However, increasing suburban sprawl also has a significant negative affect on aquatic habitats. From 1982 to 2012, developed land increased by almost three...
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Major population centers exist on most of the islands, particularly on O’ahu which has a densely populated urban core. Urban sprawl increased by 76,000 acres from 1982 to 2012, which equals about two percent of Hawaii’s land mass. Urbanization results in physical loss of aquatic habitat as well as polluted runoff and altered hydrology. The Hawaiian Department of Health in 2015 listed sediment, nutrients, and bacteria as the most common threats to aquatic ecosystems and human health and that the vast majority of impaired sites are marine areas. Development contributes excessive sedimentation through improperly constructed roads and drainage systems, poor construction practices, and to nutrient loading through landscape...
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Wheat and corn are the two most commonly grown crops in Kansas and Oklahoma and zones with a high risk of habitat degradation in eastern Kansas and Oklahoma correspond to areas of these and other row crops. Texas grew 6.2 million acres of cotton in 2014-15 predominately in the panhandle region, which was projected to be at high risk of fish habitat deterioration. Nutrient runoff from crop fields from all southern plains states not only affects local streams but eventually ends up in estuaries and the Gulf of Mexico. This high-nutrient runoff contributes to a low oxygen dead zone which annually averages over 5,000 square miles in size in the northern Gulf of Mexico and causes fish kills.
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Water projects that include large dams and water withdrawal systems alter seasonal and daily water flows (hydrology) and water temperatures, adversely affecting desert species that are adapted to the natural cycles in this region. Combined with water diversions for domestic and agricultural use, drought conditions from 2010 to 2015 in the Southwest adversely affected all desert aquatic habitats. Large rivers in the Southwest states, such as the Colorado River and the Rio Grande, have been greatly affected by the construction of dams and diversions that: interfere with fish migration; alter in-stream habitat characteristics including sediment and woody debris movement; change water quality and temperature; reduce...
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Several species of riparian plants including the non-native red mangrove ( Rhizophora mangle) and hau bush ( Hibiscus tiliaceus) proliferated along lower stream channels and estuary banks, disrupting energy flow in affected systems (a key fish habitat process). These invasive plants excessively shade estuarine shorelines, add large amounts of decomposing leaf litter that reduces water quality, create physical barriers to fish and invertebrate migration, and displace native fish and bird species. A pilot project in Wai ‘Opae, Hawai’i evaluated if red mangrove could be controlled and ultimately eradicated 20 acres of this plant. A cooperative Partnership project was initiated in 2015 to remove a large stand of invasive...


map background search result map search result map Description of Urban Land Use as a Human Activity Fffecting Fish Habitat in Southeast Atlantic States Description of dams and other barriers as a human activity affecting fish habitat in Northeastern States Description of Agriculture as a Human Activity Affecting Fish Habitat in Southern Plains States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Pacific Coast States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Mountain States Description of Pollution as a Human Activity Affecting Fish Habitat in Upper Midwest States Description of Dams and Other Barriers as a Human Activity Affecting Fish Habitat in Southwestern States Description of Competing Freshwater Demands as a Human Activity Affecting Fish Habitat in Alaska Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Eastern Gulf of Mexico States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Central Midwest States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Alaska Description of Urban Land Use and Pollution as Human Activities Affecting Fish Habitat in Mid-Atlantic States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Northeastern States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Hawaii Description of Pasture as a Human Activity Affecting Fish Habitat in Northern Plains States Description of Invasive Vegetation as a Human Activity Affecting Fish Habitat in Hawaii Description of Dams and Other Barriers as a Human Activity Affecting Fish Habitat in Central Midwest States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Upper Midwest States Description of Agriculture as a Human Activity Affecting Fish Habitat in Mountain States Description of Agriculture as a Human Activity Affecting Fish Habitat in Northern Plains States Description of Urban Land Use and Pollution as Human Activities Affecting Fish Habitat in Mid-Atlantic States Description of Urban Land Use as a Human Activity Fffecting Fish Habitat in Southeast Atlantic States Description of Pasture as a Human Activity Affecting Fish Habitat in Northern Plains States Description of Agriculture as a Human Activity Affecting Fish Habitat in Northern Plains States Description of dams and other barriers as a human activity affecting fish habitat in Northeastern States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Northeastern States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Central Midwest States Description of Dams and Other Barriers as a Human Activity Affecting Fish Habitat in Central Midwest States Description of Pollution as a Human Activity Affecting Fish Habitat in Upper Midwest States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Upper Midwest States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Eastern Gulf of Mexico States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Pacific Coast States Description of Dams and Other Barriers as a Human Activity Affecting Fish Habitat in Southwestern States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Mountain States Description of Agriculture as a Human Activity Affecting Fish Habitat in Mountain States Description of Agriculture as a Human Activity Affecting Fish Habitat in Southern Plains States Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Hawaii Description of Invasive Vegetation as a Human Activity Affecting Fish Habitat in Hawaii Description of Competing Freshwater Demands as a Human Activity Affecting Fish Habitat in Alaska Description of Urban Land Use as a Human Activity Affecting Fish Habitat in Alaska