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Research about North Dakota, South Dakota

Source-linked reports with geographic coverage including North Dakota, South Dakota.

At least 37 records · Page 2Linked to original sources

Pesticide concentrations in wetlands on the Lake Traverse Indian Reservation, South and North Dakota, July 2015

During July 2015, water samples were collected from 18 wetlands on the Lake Traverse Indian Reservation in northeastern South Dakota and southeastern North Dakota and analyzed for physical properties and 54 pesticides. This study by the U.S. Geological Survey in cooperation with the Sisseton-Wahpeton Oyate was designed to provide an update on pesticide concentrations of the same 18 wetlands that were sampled for a reconnaissance-level assessment during July 2006. The purpose of this report is to present the results of the assessment of pesticide concentrations in selected Lake Traverse Indian Reservation wetlands during July 2015 and provide a comparison of pesticide concentrations between 2006 and 2015. Of the 54 pesticides that were analyzed for in the samples collected during July 2015, 47 pesticides were not detected in any samples. Seven pesticides—2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT); 2,4–D; acetachlor; atrazine; glyphosate; metolachlor; and prometon—were detected in the 2015 samples with estimated concentrations or concentrations greater than the laboratory reporting level, and most pesticides were detected at low concentrations in only a few samples. Samples from all wetlands contained at least one detected pesticide. The maximum number of pesticides detected in a wetland sample was six, and the median number of pesticides detected was three. The most commonly detected pesticides in the 2015 samples were atrazine and the atrazine degradate CIAT (also known as deethylatrazine), which were detected in 14 and 13 of the wetlands sampled, respectively. Glyphosate was detected in samples from 11 wetlands, and metolachlor was detected in samples from 10 wetlands. The other detected pesticides were 2,4–D (4 wetlands), acetochlor (3 wetlands), and prometon (1 wetland). The same pesticides that were detected in the 2006 samples were detected in the 2015 samples, with the exception of simazine, which was detected only in one sample in 2006. Atrazine and CIAT were the most commonly detected pesticides in both sampling years; however, atrazine and CIAT were detected in fewer wetlands in 2015 (14 and 13 wetlands, respectively) than in 2006 (17 wetlands for both pesticides). The pesticides 2,4–D and prometon also were detected in fewer wetlands in 2015 than 2006, and simazine was only detected in 2006. In contrast, acetochlor, glyphosate, and metolachlor were detected in samples from more wetlands in 2015 than in 2006. In samples from individual wetlands, the number of pesticides detected was similar between 2006 and 2015. At least one pesticide was detected in all wetlands in 2015, and all but one wetland had pesticide detections in 2006. Concentrations of pesticides detected in samples from wetlands were compared to selected water-quality (human-health and aquatic-life) benchmarks. None of the concentrations in either 2006 or 2015 were greater than water-quality benchmarks, with the exception of atrazine. All detections of atrazine in the 2006 and 2015 samples were greater than the acute benchmark of 0.001 microgram per liter (μg/L) for vascular plants. In addition, some concentrations of 2,4–D and atrazine were within an order of magnitude of a water-quality benchmark. The 2,4–D concentrations in the 2015 samples from three wetlands were within an order of magnitude of the U.S. Environmental Protection Agency’s Maximum Contaminant Level of 70 μg/L (that is, sample concentrations were greater than 7.0 μg/L). The maximum dissolved atrazine concentration of 0.185 μg/L in the 2015 samples along with the concentrations in 2006 samples from two wetlands were within an order of magnitude of the acute benchmark of less than 1 μg/L for nonvascular plants (that is, concentrations were greater than 0.1 μg/L).

North Dakota, South Dakota↗

Assessing spring direct mortality to avifauna from wind energy facilities in the Dakotas

T he Northern Great Plains (NGP) contains much of the remaining temperate grasslands, an ecosystem that is one of the most converted and least protected in the world. Within the NGP, the Prairie Pothole Region (PPR) provides important habitat for >50% of North America's breeding waterfowl and many species of shorebirds, waterbirds, and grassland songbirds. This region also has high wind energy potential, but the effects of wind energy developments on migratory and resident bird and bat populations in the NGP remains understudied. This is troubling considering >2,200 wind turbines are actively generating power in the region and numerous wind energy projects have been proposed for development in the future. Our objectives were to estimate avian and bat fatality rates for wind turbines situated in cropland- and grassland-dominated landscapes, document species at high risk to direct mortality, and assess the influence of habitat variables on waterfowl mortality at 2 wind farms in the NGP. From 10 March to 7 June 2013–2014, we completed 2,398 searches around turbines for carcasses at the Tatanka Wind Farm (TAWF) and the Edgeley-Kulm Wind Farm (EKWF) in South Dakota and North Dakota. During spring, we found 92 turbine-related mortalities comprising 33 species and documented a greater diversity of species ( n  = 30) killed at TAWF (predominately grassland) than at EKWF ( n  = 9; predominately agricultural fields). After accounting for detection rates, we estimated spring mortality of 1.86 (SE = 0.22) deaths/megawatt (MW) at TAWF and 2.55 (SE = 0.51) deaths/MW at EKWF. Waterfowl spring (Mar–Jun) fatality rates were 0.79 (SE = 0.11) and 0.91 (SE = 0.10) deaths/MW at TAWF and EKWF, respectively. Our results suggest that future wind facility siting decisions consider avoiding grassland habitats and locate turbines in pre-existing fragmented and converted habitat outside of high densities of breeding waterfowl and major migration corridors.

North Dakota, South Dakota↗

Land use effects on pesticides in sediments of prairie pothole wetlands in North and South Dakota

Prairie potholes are the dominant wetland type in the intensively cultivated northern Great Plains of North America, and thus have the potential to receive pesticide runoff and drift. We examined the presence of pesticides in sediments of 151 wetlands split among the three dominant land use types, Conservation Reserve Program (CRP), cropland, and native prairie, in North and South Dakota in 2011. Herbicides (glyphosate and atrazine) and fungicides were detected regularly, with no insecticide detections. Glyphosate was the most detected pesticide, occurring in 61% of all wetlands, with atrazine in only 8% of wetlands. Pyraclostrobin was one of five fungicides detected, but the only one of significance, being detected in 31% of wetlands. Glyphosate was the only pesticide that differed by land use, with concentrations in cropland over four-times that in either native prairie or CRP, which were equal in concentration and frequency of detection. Despite examining several landscape variables, such as wetland proximity to specific crop types, watershed size, and others, land use was the best variable explaining pesticide concentrations in potholes. CRP ameliorated glyphosate in wetlands at concentrations comparable to native prairie and thereby provides another ecosystem service from this expansive program.

North Dakota, South Dakota↗

Effects of wind-energy facilities on grassland bird distributions

The contribution of renewable energy to meet worldwide demand continues to grow. Wind energy is one of the fastest growing renewable sectors, but new wind facilities are often placed in prime wildlife habitat. Long-term studies that incorporate a rigorous statistical design to evaluate the effects of wind facilities on wildlife are rare. We conducted a before-after-control-impact (BACI) assessment to determine if wind facilities placed in native mixed-grass prairies displaced breeding grassland birds. During 2003–2012, we monitored changes in bird density in 3 study areas in North Dakota and South Dakota (U.S.A.). We examined whether displacement or attraction occurred 1 year after construction (immediate effect) and the average displacement or attraction 2–5 years after construction (delayed effect). We tested for these effects overall and within distance bands of 100, 200, 300, and >300 m from turbines. We observed displacement for 7 of 9 species. One species was unaffected by wind facilities and one species exhibited attraction. Displacement and attraction generally occurred within 100 m and often extended up to 300 m. In a few instances, displacement extended beyond 300 m. Displacement and attraction occurred 1 year after construction and persisted at least 5 years. Our research provides a framework for applying a BACI design to displacement studies and highlights the erroneous conclusions that can be made without the benefit of adopting such a design. More broadly, species-specific behaviors can be used to inform management decisions about turbine placement and the potential impact to individual species. Additionally, the avoidance distance metrics we estimated can facilitate future development of models evaluating impacts of wind facilities under differing land-use scenarios.

North Dakota, South Dakota↗

Impacts of climate change on land-use and wetland productivity in the Prairie Pothole Region of North America

Wetland productivity in the Prairie Pothole Region (PPR) of North America is closely linked to climate. A warmer and drier climate, as predicted, will negatively affect the productivity of PPR wetlands and the services they provide. The effect of climate change on wetland productivity, however, will not only depend on natural processes (e.g., evapotranspiration), but also on human responses. Agricultural land use, the predominant use in the PPR, is unlikely to remain static as climate change affects crop yields and prices. Land use in uplands surrounding wetlands will further affect wetland water budgets and hence wetland productivity. The net impact of climate change on wetland productivity will therefore depend on both the direct effects of climate change on wetlands and the indirect effects on upland land use. We examine the effect of climate change and land-use response on semipermanent wetland productivity by combining an economic model of agricultural land-use change with an ecological model of wetland dynamics. Our results suggest that the climate change scenarios evaluated are likely to have profound effects on land use in the North and South Dakota PPR, with wheat displacing other crops and pasture. The combined pressure of land-use and climate change significantly reduces wetland productivity. In a climate scenario with a +4 °C increase in temperature, our model predicts that almost the entire region may lack the wetland productivity necessary to support wetland-dependent species.

North Dakota, South Dakota↗

Field‐readable alphanumeric flags are valuable markers for shorebirds: use of double‐marking to identify cases of misidentification

Implicit assumptions for most mark-recapture studies are that individuals do not lose their markers and all observed markers are correctly recorded. If these assumptions are violated, e.g., due to loss or extreme wear of markers, estimates of population size and vital rates will be biased. Double-marking experiments have been widely used to estimate rates of marker loss and adjust for associated bias, and we extended this approach to estimate rates of recording errors. We double-marked 309 Piping Plovers ( Charadrius melodus ) with unique combinations of color bands and alphanumeric flags and used multi-state mark recapture models to estimate the frequency with which plovers were misidentified. Observers were twice as likely to read and report an invalid color-band combination (2.4% of the time) as an invalid alphanumeric code (1.0%). Observers failed to read matching band combinations or alphanumeric flag codes 4.5% of the time. Unlike previous band resighting studies, use of two resightable markers allowed us to identify when resighting errors resulted in reports of combinations or codes that were valid, but still incorrect; our results suggest this may be a largely unappreciated problem in mark-resight studies. Field-readable alphanumeric flags offer a promising auxiliary marker for identifying and potentially adjusting for false-positive resighting errors that may otherwise bias demographic estimates.

North Dakota, South Dakota↗

A graphic presentation of stream gain or loss as an aid in understanding streamflow characteristics

A graphic presentation of cumulative monthly stream gain or loss on a given stream reach is used as a tool to show whether the stream gain or loss is apparent or real, and to determine the magnitude, time, and cause of the gain or loss. The graphic method could also be used to determine how much of the base flow is ground-water discharge. Interpretations of the cumulative gain or loss graph are described for three reaches on the James River in northeastern South Dakota and southeastern North Dakota.

North Dakota, South Dakota↗

Pesticide concentrations in wetlands on the Lake Traverse Reservation, South and North Dakota, July 2006

During July 2006, water samples were collected from selected Lake Traverse wetlands within the historic Reservation boundary in northeastern South Dakota and southeastern North Dakota as part of a reconnaissance-level assessment by the U.S. Geological Survey (USGS) and Sisseton-Wahpeton Oyate (SWO) Sioux Tribe. Eighteen wetlands were sampled by the SWO and USGS personnel after primary pesticide application occurred on the Lake Traverse Reservation. Samples were analyzed for 61 pesticide compounds. In addition, the samples were analyzed for physical properties that might help further characterize the water quality of the wetlands. During July 2006, water samples were collected from 18 wetlands and were analyzed for 61 widely used pesticide compounds. Pesticides were detected in 17 of the 18 sampled wetlands. In the 17 wetlands in which pesticides weredetected, the number of pesticides detected ranged from two to eight. Of the 61 pesticides for which the samples were analyzed, 51 pesticides were not detected in any of the wetland samples. Ten pesticides were detected in water samples from at least one of the wetlands at small concentrations. Atrazine and de-ethyl atrazine were detected in samples from 17 of the 18 wetlands. The minimum, maximum, and median concentrations of dissolved atrazine detected were 0.007, 0.12, and 0.064 microgram per liter (?g/L), respectively. Two pesticides (picloram and simazine) were detected in only one wetland each. None of the pesticide concentrations exceeded any U.S. Environmental Protection Agency Maximum Contaminant Levels for drinking water, and concentrations were much less than levels considered toxic for humans or aquatic species.

North Dakota, South Dakota↗

Water, bed-sediment, and fish-tissue quality within the Standing Rock Sioux Reservation, North Dakota and South Dakota, September 2006

During September 2006, samples from public water-delivery systems, ground water, surface water, bed-sediment, and fish-tissue sources were collected at 32 locations within the Standing Rock Sioux Reservation and analyzed to aid in the evaluation of any immediate water-quality concerns. Samples were collected from Solen, Selfridge, and Fort Yates, North Dakota, water-delivery systems and included raw water samples and treated water samples from water users on the water-delivery systems. Samples from the Solen and Selfridge systems were analyzed for dissolved major inorganic and dissolved minor and trace inorganic concentrations. Samples from the Fort Yates system were analyzed for dissolved major inorganic concentrations, dissolved minor and trace inorganic concentrations, total and dissolved nutrient concentrations, total and dissolved organic carbon concentrations, and volatile organic compound concentrations. Water samples were collected from ground-water wells throughout the reservation only in North Dakota and analyzed for dissolved major inorganic concentrations and dissolved minor and trace inorganic concentrations. Water samples were collected at locations on the Missouri River and its major tributaries within the reservation and analyzed for dissolved major inorganic concentrations and dissolved minor and trace inorganic concentrations; bed sediment was collected at these sites and analyzed for minor and trace inorganic concentrations. Fish-tissue and liver samples were collected from several species on the Missouri River near Fort Yates and analyzed for minor and trace inorganic concentrations. Results of the water-quality analysis revealed very little of concern, with the exception of elevated boron concentrations in the drinking water and ground water in the area of Selfridge and Solen and minor exceedences of total trihalomethanes in the Fort Yates water-delivery system.

North Dakota, South Dakota↗

Could blackbird mortality from avicide DRC-1339 contribute to avian botulism outbreaks in North Dakota?

Blackbird (family lcteridae) depredation on sunflower (Helianthus annuus) crops in the prairie states of the United States has motivated the proposed use of an avicide, DRC-1339 (3-chloro-4-methylaniline), to decrease their numbers. The resulting mortality of blackbirds at wetland roosts could increase the potential of avian botulism occurring in affected marshes. To assess this possibility, we seeded (artificially placed) blackbird carcasses in selected wetlands in Stutsman County, North Dakota, during August-September 2000 and July-September 2001 to evaluate their rate of decomposition and role in initiating avian botulism outbreaks. We monitored carcasses to determine their persistence, the frequency and amount of maggots produced, and the presence of type C botulinum toxin. In 10 of our 12 study wetlands, blackbird carcasses were not rapidly removed by scavengers, thus providing substrate for maggot growth and potential production of Clostridium botulinum toxin. Decomposition of carcasses occurred rapidly, and maggot production averaged 4a??5 g per carcass within 9 days. We were unable to detect C. botulinum type C toxin in any of the 377 blackbird carcasses or the 112 samples of maggots we collected in 2000 or 2001. None of the 25 blackbird carcasses we tested contained botulinum spores, the most probable explanation for the absence of botulinum toxin production. Our results indicate that the likelihood of DRC-1339-poisoned blackbirds causing botulism outbreaks would be minimal in North Dakota wetlands during late summer and early autumn.

North Dakota, South Dakota↗

Nontarget bird exposure to DRC-1339 during fall in North Dakota and spring in South Dakota

Blackbirds frequently use ripening sunflower ( Heltantbus annuus ) as a food source in the northern Great Plains. In 1999 and 2000, the avicide DRC-1339 (3-chloro-4-methylaniline hydrochloride) was used experimentally on fall-ripening sunflower fields in North Dakota so researchers could evaluate its effectiveness for reducing crop depredations by blackbirds. DRC-1339 was applied to rice and broadcast on the ground in a confined area within ripening sunflower fields. One objective of this study was to determine whether nontarget birds, birds other than blackbirds, were eating rice and were exposed to the DRC-1339. In 1999, 8 of 11 (73%) sparrows collected by shotgun in sunflower fields treated with DRe-1339 had rice in their gastrointestinal (GI) tracts. In 2000, 5 mourning doves ( Zenaida macroura ) and 3 sparrows were collected by shotgun in sunflower fields treated with DRC-1339. Three doves had rice in their GI tracts, 4 doves and all 3 sparrows had measurable DRC1339 concentrations in their GI tracts, and 3 mourning doves and 1 savannah sparrow ( Passerculus sanduncbensis ) exhibited histopathological signs of kidney damage. In April 2002, untreated rice was applied to corn stubble plots in South Dakota to determine which bird species ate rice. In 2002, 3 of 3 song sparrows ( Melospiza melodia ) collected by shotgun had rice in their GI tracts. Our results demonstrate that the use of DRC-1339 to control blackbirds in the northern Great Plains will likely expose nontarget birds to the DRC-1339 bait.

North Dakota, South Dakota↗

Water resources of the Lake Traverse Reservation, South and North Dakota, and Roberts County, South Dakota

In 1994, the U.S. Geological Survey, in cooperation with the Sisseton-Wahpeton Sioux Tribe; Roberts County; and the South Dakota Department of Environment and Natural Resources, Geological Survey Program, began a 6-year investigation to describe and quantify the water resources of the area within the 1867 boundary of the Lake Traverse Reservation and adjacent parts of Roberts County. Roberts County is located in extreme northeastern South Dakota, and the 1867 boundary of the Lake Traverse Reservation encompasses much of Roberts County and parts of Marshall, Day, Codington, and Grant Counties in South Dakota and parts of Richland and Sargent Counties in southeast North Dakota. This report includes descriptions of the quantity, quality, and availability of surface and ground water, the extent of the major glacial and bedrock aquifers and named outwash groups, and surface- and ground-water uses within the 1867 boundary of the Lake Traverse Reservation and adjacent parts of Roberts County. The surface-water resources within the 1867 boundary of the Lake Traverse Reservation and adjacent parts of Roberts County include rivers, streams, lakes, and wetlands. The Wild Rice and Bois de Sioux Rivers are tributaries of the Red River within the Souris-Red-Rainy River Basin; the Little Minnesota, Jorgenson, and North Fork Whetstone Rivers are tributaries of the Minnesota River within the Upper Mississippi River Basin, and the James and Big Sioux Rivers are tributaries within the Missouri River Basin. Several of the larger lakes within the study area have been developed for recreation, while many of the smaller lakes and wetlands are used for livestock watering or as wildlife production areas. Statistical summaries are presented for the water-quality data of six selected streams within the study area, and the dominant chemical species are listed for 17 selected lakes within the study area. The glacial history of the study area has led to a rather complex system of glacial aquifers. The boundaries of 11 aquifers and 6 named outwash groups were delineated based on hydrogeologic cross sections, water levels, and water-quality similarities/dissimilarities. The glacial aquifers include Coteau Lakes system, Big Sioux, Alta-mont, Revillo, James, Veblen system, Spiritwood, Hankinson, Rosholt, Milnor Channel, and Fairmount; the bedrock aquifer included in this report is the Dakota. Named outwash groups include the Prairie Coteau, Lonesome Lake, Marday, Eden, Roslyn, and Wilmot. A summary of the character-istics of each of the major aquifers and outwash groups and a summary of selected chemical analyses for each aquifer and outwash group are presented. All aquifers and outwash groups in the study area have either moderately hard or very hard water and are considered fresh to slightly saline. One or more water samples from some of the aquifers and outwash groups have a constituent that was above the recommended or mandatory limit for drinking water. Most aquifers and outwash groups have dissolved solids and sulfate contents above the recommended levels of 500 and 250 mg/L (milligrams per liter), respectively. The Dakota aquifer was the only one to have a mean chloride concentration above the recommended level of 250 mg/L. Nitrate concentrations greater than the mandatory limit of 10 mg/L were found in the Big Sioux aquifer and the Coteau Lakes and Veblen aquifer systems. Concentrations of arsenic greater than 10 ?g/L (micrograms per liter) were found in the Coteau Lakes and Veblen aquifer systems, and in the Rosholt and Fairmount aquifers. Municipalities and rural water systems currently provide most of the water used in the study area-nearly all of it from ground-water sources. Surface-water use is limited to livestock watering. About 55 percent of the total water used in Roberts County is for domestic purposes, with most domestic users served by a public supply system. Irrigation accounts for about 10 percent of the total water used. All

North Dakota, South Dakota↗

Coefficients of conservatism for the vascular flora of the Dakotas and adjacent grasslands

Floristic quality assessment can be used to identity natural areas, to facilitate comparisons among different sites, to provide long-term monitoring of natural area quality, and to evaluate habitat management and restoration efforts. To facilitate the use of floristic quality assessment in North Dakota, South Dakota (excluding the Black Hills), and adjacent grasslands, we developed a species list and assigned coefficients of conservatism (C values; range 0 to 10) to each plant species in the region's flora. The C values we assigned represented our collective knowledge of the patterns of occurrence of each plant species in the Dakotas and our confidence that a particular taxon is natural-area dependent. Because state boundaries usually do not follow ecological boundaries, the C values we assigned should be equally valid in nearby areas with the same vegetation types. Of the 1,584 taxa we recognized in this effort, 275 (17%) were determined to be nonnative to the region. We assigned C values of 4 or higher to 77% of our taxa, and the entire native flora had a mean C value (C) of 6.l. A floristic quality index (FQI) can be calculated to rank sites in order of their floristic quality. By applying the coefficients of conservatism supplied here and calculating C and FQI, an effective means of evaluating the quality of plant communities can be obtained. Additionally, by repeating plant surveys and calculations of C and FQI over time, temporal changes in floristic quality can be identified.

North Dakota, South Dakota↗

Development of historic and synthesized unregulated streamflow for the James River in North Dakota and South Dakota, 1983-91

Operation of the Garrison Diversion Unit may have some affect on the hydrology of the James River in North Dakota and South Dakota. The Garrison Diversion Unit Monthly Operations Model was developed to analyze a wide range of streamflow conditions that could occur in the James River Basin. The purpose of this study was to compute monthly streamflows that are required as input to the model. Historic streamflow data were complied and record extension methods were used, when necessary, to compute monthly streamflow for 1983-91 for 15 gaging stations on the James River in North Dakota and South Dakota. The record extension methods used include Maintenance of Variance Extension Type 1, Ordinary Least Squares, and drainage-area ratio. In addition to the historic streamflow, synthesized unregulated streamflow was computed for the 15 gaging stations on the James River for 1983-91 by eliminating the effects of Jamestown Reservoir, Pipestem Reservoir, Sand Lake National Wildlife Refuge, consumptive surface-water withdrawals, and wastewater withdrawals. Maintenance of Variance Extension Type 1, Ordinary Least Squares regression, water-balance procedures, and drainage-area ratio method were used to compute the unregulated streamflows.

North Dakota, South Dakota↗

Conservation reserve program: benefit for grassland birds in the northern plains

During the past few decades numbers of some species of upland-nesting birds in North America have declined. Duck species such as mallard (Anas platyrhynchos), northern pintail (A. acuta) and blue-winged teal (A. discors) have declined since the early 1970s and have remained low since 1985 (Caithamer et al. 1993). Some grassland-dependent nonwaterfowl species also have declined since 1966, as indicated by the North American Breeding Bird Survey (BBS) (Robbins et al. 1986). For prairie-nesting ducks, population declines can be attributed mostly to low recruitment, partially as a result of low nest success. Klett et al. (1988) concluded that nest success (probability of ≥1 egg of clutch hatches) in much of the U.S. Prairie Pothole Region was inadequate to maintain populations of the five most common upland-nesting duck species studied, and that predators were the most important cause of nest failure. Over the years, as grassland areas have been converted to cropland, ducks have concentrated their nesting in the remaining areas of available habitat, where predators such as red fox (Vulpes vulpes), striped skunk (Mephitis mephitis) and badger (Taxidea taxus) forage (Cowardin et al. 1983). The reasons for declining populations of grassland nonwaterfowl birds are not clear but the loss of suitable grassland-nesting habitat probably is an important factor. Currently, approximately 95 percent of the land in North Dakota is used for agricultural purposes, of which over 60 percent is used for annual crop production (Haugse 1990). Of the grassland that remains, 95 percent is used for livestock production. This probably had a severe impact on grassland bird species that seek idle grass cover for nesting. The 1985 and 1990 U.S. Farm Bills include provisions under the Food Security Act to fund a cropland-idling program called the Conservation Reserve Program (CRP). Over 36 million acres have been enrolled nationwide in the CRP since 1985 (Osborn 1993), and up to 25 percent of cropland in some counties has been converted primarily to grass. In North Dakota, nearly 3 million acres have been enrolled. Over 90 percent of the CRP plantings in North Dakota are grass and grass-legume mix composed primarily of wheatgrass (Agropyron spp.), smooth brome (Bromus inermis), alfalfa (Medicago saliva) and sweetclover (Melilotus spp.). Mixes of these species have been reported to attract high densities of nesting ducks (Duebbert and Kantrud 1974). According to the CRP provisions, the land must remain idle for the 10-year contract period, with the exception of emergency provisions for haying or grazing. CRP appears to have great potential for benefiting many species of grassland-nesting birds. There have been efforts to document the importance of the CRP to migratory birds in the Upper Great Plains of the U.S. Kantrud (1993) studied duck nest success in CRP cover and concluded that nest success was higher than in planted cover on U.S. Fish and Wildlife Service (FWS) Waterfowl Production Areas (WPAs). Johnson and Schwartz (1993a) measured the use of CRP fields by nonwaterfowl birds and reported that several species have responded positively by colonizing CRP fields. They concluded that CRP has the potential to help reverse the population declines of several species. We investigated the importance of CRP to upland-nesting ducks and certain other grassland-nesting birds. For ducks, we compared nest success in CRP cover with nest success in planted cover on WPAs in the same period (1992-93) and with that of an earlier period (1980-84). For nonwaterfowl, we used BBS data to compare the trends in populations of certain species found in CRP, for the periods 1966-86 (pre-CRP cover establishment) and 1987-92 (post-CRP cover establishment) in North Dakota.

North Dakota, South Dakota↗

Dissolved-solids data for the James River salinity model, North Dakota and South Dakota

Operation of the Garrison Diversion Unit in North Dakota will divert water from the Missouri River into the James River basin and thereby augment flows in the James River sufficiently to permit expanded irrigation and to provide new water supplies for municipal and industrial use. Salinity of water in the James River currently is marginal for irrigation use f and expanded irrigation may increase river-water salinity beyond acceptable limits. Monthly mean dissolved solids are required by the U.S. Bureau of Reclamation salinity model to predict the effects of different management practices on salinity in the James River. The purpose of this report is to provide a summary of available dissolved-solids data and to discuss methodology to calculate monthly mean dissolved solids. Equations were developed by relating dissolved solids to specific conductance and also by relating specific conductance to streamflow for 15 gaging stations in the James River basin. Dissolved-solids data for supplemental surface-water and ground-water sources to the James River also are summarized.

North Dakota, South Dakota↗