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Shannon K. Brewer

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Habitat fragmentation and flow regulation are significant factors related to the decline and extinction of freshwater biota. Pelagic-broadcast spawning cyprinids require moving water and some length of unfragmented stream to complete their life cycle. However, it is unknown how discharge and habitat features interact at multiple spatial scales to alter the transport of semi-buoyant fish eggs. Our objective was to assess the relationship between downstream drift of semi-buoyant egg surrogates (gellan beads) and discharge and habitat complexity. We quantified transport time of a known quantity of beads using 2–3 sampling devices at each of seven locations on the North Canadian and Canadian rivers. Transport time was...
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Summary of project, results, and discussion for the study completed by Shannon K. Brewer, Thomas A. Worthington, Timothy B. Grabowski, Julia Mueller, Nicole Farless, and Mark S. Gregory. Summary written by the Great Plains Landscape Conservation Cooperative (GP LCC).
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Reduced to its most fundamental level, the management problem addressed by this project is the basic conflict between the fact that fish need water and the reality that the amount and quality of the water available has been dramatically altered by human activities. For fishes dependent upon specific flows for successful reproduction, the quality and quantity of available water are likely the primary determinants of habitat quality. In many cases, the minimum requirements of water quantity and quality needed to support self-sustaining fish populations are unknown and thus there is no way for resource managers to effectively assess habitat quality and its ability to support fish populations under current or future...
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2011, Academics & scientific researchers, Arkansas River shiner (Notropis girardi), Arkansas River shiner (Notropis girardi), CATFISHES/MINNOWS, All tags...
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Quantitative studies focusing on the collection of semibuoyant fish eggs, which are associated with a pelagic broadcast-spawning reproductive strategy, are often conducted to evaluate reproductive success. Many of the fishes in this reproductive guild have suffered significant reductions in range and abundance. However, the efficiency of the sampling gear used to evaluate reproduction is often unknown and renders interpretation of the data from these studies difficult. Our objective was to assess the efficiency of a modified Moore egg collector (MEC) using field and laboratory trials. Gear efficiency was assessed by releasing a known quantity of gellan beads with a specific gravity similar to that of eggs from representatives...
Abstract (from Wiley Online Library): Species detection error (i.e., imperfect and variable detection probability) is an essential consideration when investigators map distributions and interpret habitat associations. When fish detection error that is due to highly variable instream environments needs to be addressed, sand‐bed streams of the Great Plains represent a unique challenge. We quantified seining detection probability for diminutive Great Plains fishes across a range of sampling conditions in two sand‐bed rivers in Oklahoma. Imperfect detection resulted in underestimates of species occurrence using naïve estimates, particularly for less common fishes. Seining detection probability also varied among fishes...
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