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Partnerships - Driftless Area Restoration Effort, Great Lakes Basin Fish Habitat Partnership, Great Plains Fish Habitat Partnership, Midwest Glacial Lakes Partnership, Fishes and Farmers Partnership, and Reservoir Fisheries Habitat Partnership Partners removed: one barrier in Minnesota that increased fish passage to over 3 miles of streams; 12 barriers in Wisconsin that increased fish passage by 12 miles and reconnected 15 acres of wetlands to streams; and 13 barriers in Michigan that reconnected over 147 miles of streams. In Wisconsin, enhanced 13.0 stream miles for Brook Trout including tributary spawning habitat, 20.5 miles of mixed Brook/Brown Trout water, and 13.2 miles of stream for Brown Trout. Improved...
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The Prairie Chub (Macrhybopsis australis) requires streams with gravel and rock bottoms and can live with high levels of dissolved salts that occur in intermittent streams in the upper Red River Basin, Texas. This Texas-listed species of special concern is potentially threatened by large-scale chloride removal planned for the upper Red River Basin that could drastically change the stream chemistry required by this unique fish species.
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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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Arctic Grayling (Thymallus arcticus) now inhabits less than 5 percent of its historic river range in the Mountain States. This species requires high-quality coldwater habitat with long, un-fragmented reaches. Historically, glacial relict river populations were found in the Upper Missouri River Basin with another now extinct population in the Midwest (Michigan). The Arctic Grayling has been affected by water withdrawals, barriers to movement, and habitat degradation. One of the last strongholds, the Big Hole River in Montana, was reduced to a trickle in the summers of the 1990s as a result of irrigation withdrawals. Recent cooperative efforts, which include better water management, have improved populations of Arctic...
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Map of the risk of current fish habitat degradation of inland streams of the Southwestern States.
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A total of 15 large dams have been constructed along the 1,040-mile (1,674-kilometer) Snake River from its headwaters in the Rocky Mountains to its mouth on Lake Wallula, a reservoir formed behind McNary Dam on the Columbia River. Compared to the lower Snake River, the rest of the Columbia River watershed, and most of the Rocky Mountain West, the Upper Snake ecoregion has a high level of unique organisms (endemism), especially among freshwater mollusks, such as snails and clams. There are at least 21 snail and clam species of special concern, including 15 that appear to exist only in single clusters. There are 14 fish species found in the Upper Snake region that are not present elsewhere in the Columbia River watershed,...
Creating cumulative habitat condition scores Greater Alaska All six sub-indices of disturbance scores in each HUC-12 were summed together to yield a cumulative habitat condition index (CHCI) score for each HUC-12. The maximum value for the CHCI was 6, indicating that a HUC-12 was in the worst condition class for each sub-index of disturbance, while the minimum value of the CHCI was 0, indicating that a HUC-12 was in the best condition class for each sub-index of disturbance. We followed methods applied for the conterminous US and created condition classes using Jenk’s natural breaks. With the exception of the HUC-12s that received a CHCI score of <0.001, which were given a priory assignment of “very low” risk of...
Tags: 2015, Alaska, Method
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The Woundfin (Plagopterus argentissimus) once ranged from southwest Utah to southern Arizona in the Colorado and Gila River basins, but now only occur in 12 percent of its historical range, and is classified as critically endangered. It prefers quiet water adjacent to riffles of swift, warm, turbid small to medium rivers, but spawns in swifter flowing water over gravel. Populations have been affected by habitat loss, fragmentation, and degradation caused by dams and water diversions. Woundfin populations have also shown declines in areas where the non-native Red Shiner has proliferated due to changes in water flow patterns caused by dams and diversions. The Red Shiner is both a predator of and a competitor with...
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The Gulf Sturgeon (Acipenser oxyrinchus ssp. desotoi) as the name implies lives in the estuaries of the Gulf of Mexico but migrates up coastal rivers to spawn (anadromous). It is found in rivers from spring until fall and in the Gulf during the winter. It feeds heavily while in the Gulf, but adults eat very little (or not at all) while in the rivers. The species declined dramatically after the late 1800s. It fell victim to overharvest for its meat and roe, dam construction, and dredging activities. The largest population is currently in the Suwannee River in Florida.
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Assembling Data We used datasets of habitat stressors available at a national scale and measured within estuaries and their associated watersheds. Included datasets represent anthropogenic stressors likely to affect fish habitat within estuaries based on evidence from the published habitat ecology literature. Although many important factors were included, not all data were available at sufficient spatial resolution or geographic breadth for meaningful analysis. Some important datasets that were investigated but determined to be insufficient for inclusion in the current version of the National Estuary Assessment included: historic habitat extent/habitat loss; storm/wastewater discharges; sediment contaminants; biogenic...
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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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While this assessment has found that much of the stream habitat in this region is at low or very low risk of degradation, some key fish habitat disturbances, including water withdrawals or diversions and intensity of livestock grazing in watersheds, could not be directly included in this assessment because national datasets of these disturbances and their supporting variables are unavailable. These disturbances are known to have major, negative effects on fish habitats in this region. Their absence from this assessment, along with absences of other disturbances, has likely produced an overestimation of habitat condition (quality) for some water bodies. Despite such absences, impairment to fish habitats was determined...
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The Plains Minnow (Hybognathus placitus) is well adapted to prairie watersheds. It is found in open, shallow river channels of highly turbid rivers and creeks with sandy bottoms, high levels of dissolved solids, and slight to moderate erratic flows, typical of these watersheds. One of many issues affecting the Plains Minnow is that the construction of dams has significantly altered flow regimes in its range. Eliminating flood events has removed the historical cues for spawning and reduced spawning habitat.
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Creating cumulative habitat condition scores To create the cumulative habitat condition index (CHCI) for streams of the conterminous United States, associations between multiple fish metrics and multiple human landscape factors were synthesized into a single number using the following scoring process. 5a. For each significant association between a fish metric and a human landscape factor, we evaluated the shape of the relationship to identify two key points. The “ threshold point” is the level of a landscape factor associated with a decrease in abundance of a particular fish metric (change in condition class between 5 and 4 in Figure 4), and the “plateau point” is the level of a landscape factor beyond which increasing...
Tags: 2015, CONUS, Method
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Both Green (Acipenser medirostris) and White Sturgeon (Acipenser transmontanus) are long-lived species with delayed and intermittent spawning that require large amounts of connected habitat to complete their life cycle. Both species use inshore marine and estuarine habitat along with rivers for juvenile and adult habitat and require clean substrates in rivers to successfully spawn. Hydropower dams are barriers to movements of these species in Pacific rivers and have negatively affected spawning success by creating unstable daily water flow patterns through peaking power operations as has been documented in other sturgeon species. For example, the fragmentation of the Columbia River by dams has created 17 land-locked...
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The Pahrump Poolfish (Empetrichthys latos) is an endangered endemic springfish and is the only remaining species in its genus, Empetrichthys. Originally occurring only in a large spring in southern Nevada, its entire historic habitat was lost in the 1960s due to excessive groundwater pumping, which desiccated the spring system. This species now exists in several refuge habitats in southern and central Nevada, as efforts to restore its original habitat have thus far been unsuccessful.
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The Paddlefish (Polyodon spathula) has declined across its entire range due largely to loss of breeding habitat and overharvest, with much of it as illegal harvesting for caviar. Although conservation efforts have stabilized this species in the Central Mississippi States, a continued decline is expected due to overharvest, introduced species (particularly Asian Carp), and pollution. Other threats include channelization and dam construction that have blocked seasonal migration to suitable spawning sites which isolates individual populations and lead to breeding issues. Some characteristics of its life history, such as length of time to reach sexual maturity, make it susceptible to decline and slow to recover.
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A. Pervasive disturbances: The most common disturbances based on total stream length in a given region. Top five overall most pervasive disturbances to all stream reaches, regardless of stream size and across all spatial scales (ranked highest first): Impervious surface cover Population density Low intensity urban land use Road length density Downstream dam density Top three most pervasive disturbances to creeks (watersheds <100 km 2 in area) across all spatial scales: Impervious surface cover Low intensity urban land use Population density Top three most pervasive disturbances to rivers (watersheds >100 km 2 in area) across all spatial scales: Upstream dam density Pasture and hay land use Population...
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A. Pervasive disturbances: The most common disturbances based on total stream length in a given region. Top five overall most pervasive disturbances to all stream reaches, regardless of stream size and across all spatial scales ranked highest first): Crop land use Population density Pasture and hay land use Road crossing density Low intensity land use Top three most pervasive disturbances to creeks (watersheds <100 km 2 in area) across all spatial scales: Crop land use Population density Low intensity urban land use Top three most pervasive disturbances to rivers (watersheds >100 km 2 in area) across all spatial scales : Pasture and hay land use Population density Crop land use Top five most pervasive...
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A. Pervasive disturbances: The most common disturbances based on total stream length in a given region. Top five overall most pervasive disturbances to all stream reaches, regardless of stream size and across all spatial scales (ranked highest first): Impervious surface cover Population density Road length density Low intensity urban land use Downstream dam density Top three most pervasive disturbances to creeks (<100 km 2 watersheds) across all spatial scales : Impervious surface Road length density Low intensity urban land use Top three most pervasive disturbances to rivers (>100 km 2 watersheds) across all spatial scales : Pasture and hay land use Impervious surface Population density Top five...


map background search result map search result map Habitat Trouble for Green and White Sturgeon in Pacific Coast States Facts About Mountain States Southwestern States - Risk of Current Fish Habitat Degradation Map Fish Habitat Partnership Activities for the Upper Midwest States Most Pervasive and Severe Disturbances for the Upper Midwest States Habitat Trouble for Arctic Grayling in Mountain States Habitat Trouble for Paddlefish in Central Mississippi River States Habitat Trouble for Prairie Chub in Southern Plains States Habitat Trouble for Plains Minnow in Mountain States Description of Urban Land Use and Pollution as Human Activities Affecting Fish Habitat in Mid-Atlantic States Habitat Trouble for Pahrump Poolfish in Southwestern States Most Pervasive and Severe Disturbances for the Southeast Atlantic States ​Habitat Trouble for Gulf Sturgeon in Eastern Gulf of Mexico States Habitat Trouble for Woundfin in Southwestern States Description of Agriculture as a Human Activity Affecting Fish Habitat in Northern Plains States Summary of Scientific Findings for Southern Plains States Description of Urban Land Use and Pollution as Human Activities Affecting Fish Habitat in Mid-Atlantic States Most Pervasive and Severe Disturbances for the Southeast Atlantic States Description of Agriculture as a Human Activity Affecting Fish Habitat in Northern Plains States Habitat Trouble for Paddlefish in Central Mississippi River States Fish Habitat Partnership Activities for the Upper Midwest States Most Pervasive and Severe Disturbances for the Upper Midwest States ​Habitat Trouble for Gulf Sturgeon in Eastern Gulf of Mexico States Habitat Trouble for Green and White Sturgeon in Pacific Coast States Southwestern States - Risk of Current Fish Habitat Degradation Map Habitat Trouble for Pahrump Poolfish in Southwestern States Habitat Trouble for Woundfin in Southwestern States Facts About Mountain States Habitat Trouble for Arctic Grayling in Mountain States Habitat Trouble for Plains Minnow in Mountain States Habitat Trouble for Prairie Chub in Southern Plains States Summary of Scientific Findings for Southern Plains States