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Rapid City, SD, United States

Simpson G.,Fish and Parks | Wu Y.H.,Northwest Missouri State University
ISPRS International Journal of Geo-Information | Year: 2014

Sedimentation is a problem for all reservoirs in the Black Hills of South Dakota. Before working on sediment removal, a survey on the extent and distribution of the sediment is needed. Two sample lakes were used to determine which of three interpolation methods gave the most accurate volume results. A secondary goal was to see if fewer samples could be taken while still providing similar results. The smaller samples would mean less field time and thus lower costs. Subsamples of 50%, 33% and 25% were taken from the total samples and evaluated for the lowest Root Mean Squared Error values. Throughout the trials, the larger sample sizes generally showed better accuracy than smaller samples. Graphing the sediment volume estimates of the full sample, 50%, 33% and 25% showed little improvement after a sample of approximately 40%'50% when comparing the asymptote of the separate samples. When we used smaller subsamples the predicted sediment volumes were normally greater than the full sample volumes. It is suggested that when planning future sediment surveys, workers plan on gathering data at approximately every 5.21 meters. These sample sizes can be cut in half and still retain relative accuracy if time savings are needed. Volume estimates may slightly suffer with these reduced samples sizes, but the field work savings can be of benefit. Results from these surveys are used in prioritization of available funds for reclamation efforts. © 2014 by the authors; licensee MDPI, Basel, Switzerland. Source

Albright T.P.,SAIC | Albright T.P.,University of Nevada, Reno | Ode D.J.,Fish and Parks
Hydrobiologia | Year: 2011

Potamogeton crispus L. (curly pondweed) is a cosmopolitan aquatic macrophyte considered invasive in North America and elsewhere. Its range is expanding and, on individual water bodies, its coverage can be dynamic both within and among years. In this study, we evaluate the use of free and low-cost satellite remote sensing data to monitor a problematic emergent macrophyte community dominated by P. crispus. Between 2000 and 2006, we acquired eight satellite images of 24,000-ha Lake Sharpe, South Dakota (USA). During one of the dates for which satellite imagery was acquired, we sampled the lake for P. crispus and other emergent macrophytes using GPS and photography for documentation. We used cluster analysis to assist in classification of the satellite imagery and independently validated results using the field data. Resulting estimates of emergent macrophyte coverage ranged from less than 20 ha in 2002 to 245 ha in 2004. Accuracy assessment indicated 82% of image pixels were correctly classified, with errors being primarily due to failure to identify emergent macrophytes. These results emphasize the dynamic nature of P. crispus-dominated macrophyte communities and show how they can be effectively monitored over large areas using low-cost remote sensing imagery. While results may vary in other systems depending on water quality and local flora, such an approach could be applied elsewhere and for a variety of macrophyte communities. © Springer Science+Business Media B.V. 2010. Source

Pierce L.L.,South Dakota State University | Pierce L.L.,University of Missouri | Graeb B.D.S.,South Dakota State University | Willis D.W.,South Dakota State University | And 2 more authors.
Transactions of the American Fisheries Society | Year: 2011

Lake Francis Case, South Dakota, a Missouri River reservoir, supported a paddlefish Polyodon spathula sport fishery shortly after impoundment, but this fishery closed in 1986 owing to a lack of natural recruitment. Lake Francis Case has been stocked intermittently since 1974 and annually since 1990 to maintain the population and potentially sustain a sport harvest. To evaluate the success of these stockings, we assessed the current status of the Lake Francis Case paddlefish population (i.e., population characteristics and dynamics) and evaluated the potential effects of exploitation on this population. Advanced fingerling stockings have been effective, as 56% of sampled fish were of hatchery origin (indicated by coded wire tags), and may sustain a harvestable population. Year-class strength was negatively correlated to water temperature inputs fromBig Bend Dam and positively correlated to White River discharge. Downstream emigration is probably responsible for most of the variability in year-class strength, and the rate of downstream emigration may be greater during years with warmer water temperatures. Harvest simulations suggested that growth overfishing was possible under a 660-mm minimum length limit but not under 840-mm and 1,016-mm minimum length limits. The proportional size distribution of memorable-length fish (PSD-M) was reduced 28.6% and 14.3%, respectively, by 5% exploitation under simulated 660-mm and 840-mm minimum length limits. Under a simulated 1,016-mm minimum length limit, PSD-M was unchanged by 10% exploitation. At 5% exploitation, broodstock availability was reduced by more than 30% under the simulated 660-mm and 840-mm minimum length regulations and was reduced 16% under the 1,016-mm minimum length limit. Our results suggest that this population could support a limited (e.g., 5% exploitation) sport fishery under a high (e.g., 1,016-mm) minimum length limit without substantial changes in size structure or the availability of broodstock if stockings are continued. © American Fisheries Society 2011. Source

Barnes M.E.,Fish and Parks | Durben D.J.,Black Hills State University
Aquaculture Nutrition | Year: 2010

The addition of a proprietary, fully-fermented yeast Saccahromyces cerevisiae culture supplement (DVAqua®, Diamond V Mills, Cedar Rapids, IA, USA) was evaluated during long-term feeding of McConaughy strain rainbow trout Oncorhynchus mykiss. Beginning at initial feeding and continuing for 408 days of hatchery rearing, the trout received either a commercially-manufactured feed or the same feed containing 0.125 g kg-1 DVAqua. This study was conducted at a production level as part of normal (real-world) hatchery operations, with the fish periodically inventoried and moved into different rearing units. Although no rearing-tank replication occurred during the first 54 days of feeding, multiple tanks and raceways were used thereafter. Fish in rearing units receiving DVAqua supplementation exhibited less mortality, particularly during the earlier rearing stages. During the final 177 days of rearing in six raceways, DVAqua-fed McConaughy strain trout were significantly larger and had a significantly improved feed conversion ratio. The overall feed conversion ratio for the entire duration of the study was 1.17 in the fish receiving DVAqua supplementation compared to 1.21 in the control group. Despite the limitations of this study, the use of DVAqua is recommended for McConaughy strain rainbow trout and other less-domesticated, more difficult-to-rear salmonids. © 2009 Blackwell Publishing Ltd. No claim to original US government works. Source

Rota C.T.,University of Missouri | Millspaugh J.J.,University of Missouri | Kesler D.C.,University of Missouri | Lehman C.P.,Fish and Parks | And 2 more authors.
Journal of Animal Ecology | Year: 2013

A common sampling design in resource selection studies involves measuring resource attributes at sample units used by an animal and at sample units considered available for use. Few models can estimate the absolute probability of using a sample unit from such data, but such approaches are generally preferred over statistical methods that estimate a relative probability of use. The case-control model that allows for contaminated controls, proposed by Lancaster & Imbens (1996) and Lele (2009), can estimate the absolute probability of using a sample unit from use-availability data. However, numerous misconceptions have likely prevented the widespread application of this model to resource selection studies. We address common misconceptions regarding the case-control model with contaminated controls and demonstrate its ability to estimate the absolute probability of use, prevalence and parameters associated with categorical covariates from use-availability data. We fit the case-control model with contaminated controls to simulated data with varying prevalence (defined as the average probability of use across all sample units) and sample sizes (n1 = 500 used and na = 500 available samples; n1 = 1000 used and na = 1000 available samples). We then applied this model to estimate the probability Ozark hellbenders (Cryptobranchus alleganiensis bishopi) would use a location within a stream as a function of covariates. The case-control model with contaminated controls provided unbiased estimates of all parameters at N = 2000 sample size simulation scenarios, particularly at low prevalence. However, this model produced increasingly variable maximum likelihood estimates of parameters as prevalence increased, particularly at N = 1000 sample size scenarios. We thus recommend at least 500-1000 used samples when fitting the case-control model with contaminated controls to use-availability data. Our application to hellbender data revealed selection for locations with coarse substrate that are close to potential sources of cover. This study unites a disparate literature, addresses and clarifies many commonly held misconceptions and demonstrates that the case-control model with contaminated controls is a viable alternative for estimating the absolute probability of use from use-availability data. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society. Source

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