Predicting lesser scaup wetland use during spring migration in eastern South Dakota

S.N. Kahara; S. R. Chipps

Home/Archive/USGS

USGS · 70036849

Predicting lesser scaup wetland use during spring migration in eastern South Dakota

S.N. Kahara·S. R. Chipps

View original source ↗Export metadata ↓

Abstract

The relative influence of physical, chemical, and biotic wetland characteristics on wetland use by spring migrating lesser scaup (Aythya affinis [Eyton]; hereafter "scaup") is not well understood. We compared characteristics of used and unused wetlands in eastern South Dakota. Used wetlands were larger (>2 ha; P = 0.05), with higher amphipod densities (>500 individuals m -2 ; P = 0.01) and higher chlorophyll-a concentrations (>0.2; P < 0.05). These wetlands had lower ionic conductivity (1.8 mS; P = 0.02), lower nitrates (1.0 ppm; P = 0.01), lower submerged aquatic vegetation density (P < 0.01), and lower fine sediment proportions (???150 ??m grain size; P < 0.01). Wetland use was best described by amphipod and submerged aquatic vegetation densities. The predictive model explained 50.4% of the variation in scaup use in a reserve dataset. Thresholds of tolerance by amphipods in relation to wetland habitats in the upper Midwest should be investigated further as indicators of a broader range of water and habitat quality characteristics for scaup. ?? 2009 Copyright by the Center for Great Ploins Studies, University of Nebraska-Lincoln.

Explore related subjects

Great Plains Research Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

S.N. Kahara, S. R. Chipps. 2009. Predicting lesser scaup wetland use during spring migration in eastern South Dakota. https://pubs.usgs.gov/publication/70036849

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2015

Masked expression of life-history traits in a highly variable environment

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation often inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that differ in environmental variability (i.e., annual water-level fluctuation) to identify the capacity of phenotypic expression and the corresponding association with age. Despite significant differences in female body and liver masses between reservoirs that differ in environmental variability, we found no difference in reproductive investment measured by egg size and fecundity. Walleye in a highly variable environment appear to exhibit reproductive traits more typical of a short-lived life-history strategy, which may be resultant from the interaction of environmental and anthropogenic pressures. This finding emphasizes the need to identify the degree to which life-history expression represents physiological constraints versus ecological optimization, particularly as anthropogenic change continues to alter environmental conditions.

Great Plains Research↗

USGS2015

Experimental flights using a small unmanned aircraft system for mapping emergent sandbars

The US Geological Survey and Parallel Inc. conducted experimental flights with the Tarantula Hawk (T-Hawk) unmanned aircraft system (UAS ) at the Dyer and Cottonwood Ranch properties located along reaches of the Platte River near Overton, Nebraska, in July 2013. We equipped the T-Hawk UAS platform with a consumer-grade digital camera to collect imagery of emergent sandbars in the reaches and used photogrammetric software and surveyed control points to generate orthophotographs and digital elevation models (DEMS ) of the reaches. To optimize the image alignment process, we retained and/or eliminated tie points based on their relative errors and spatial resolution, whereby minimizing the total error in the project. Additionally, we collected seven transects that traversed emergent sandbars concurrently with global positioning system location data to evaluate the accuracy of the UAS survey methodology. The root mean square errors for the elevation of emergent points along each transect across the DEMS ranged from 0.04 to 0.12 m. If adequate survey control is established, a UAS combined with photogrammetry software shows promise for accurate monitoring of emergent sandbar morphology and river management activities in short (1–2 km) river reaches.

Nebraska↗

USGS2014

Status of native stream fishes within selected protected areas of Niobrara River in western Nebraska

Lotic systems within the Great Plains are characterized by highly fluctuating conditions through both space and time. Fishes inhabiting these systems have adopted specific life-history strategies to survive in such environments; however, anthropogenic disturbance to prairie streams has resulted in declines and extirpation of many native stream fishes. Terrestrial protected areas (i.e., parks and reserves) are designated to support native flora and fauna and, it is assumed, to provide protection to native fishes. We assessed the presence and relative abundance of stream fish populations within protected areas along the Niobrara River in western Nebraska based on data collected during 1979, 1989, 2008, and 2011. The spatial extent of protection, landscape changes resulting in degraded physiochemical parameters, and introduced species may reduce the effectiveness of these terrestrial protected areas in protecting native fishes in Great Plains stream environments.

Great Plains Research↗