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Tyler Wagner

We present a case-study evaluation of gillnet catches of Walleye Sander vitreus to assess potential effects of large-scale changes in Oneida Lake, New York, including disruption of trophic interactions by double-crested cormorants Phalacrocorax auritus and invasive dreissenid mussels. We used the empirical long-term gillnet time series and a negative binomial linear mixed model to partition variability into spatial and coherent temporal variance components, and we propose that variance partitioning can help quantify spatiotemporal variability and examine if variance structure differs before and after large-scale perturbation. Here, we found that average catch and total variability of catches decreased following...
Abstract (from http://www.tandfonline.com/doi/full/10.1080/00028487.2016.1150879): Long-term sampling of fisheries data is an important source of information for making inferences about the temporal dynamics of populations that support ecologically and economically important fisheries. For example, time series of catch-per-effort data are often examined for the presence of long-term trends. However, it is also of interest to know whether certain sampled locations are exhibiting temporal patterns that deviate from the overall pattern exhibited across all sampled locations. Patterns at these “unusual” sites may be the result of site-specific abiotic (e.g., habitat) or biotic (e.g., the presence of an invasive species)...
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Projected Vulnerability of Brook Trout to Climate and Land Use Changes in the Eastern U.S. (Regional Assessment)
Throughout its native range in the Eastern U.S., the brook trout is a culturally and economically important species that is sensitive to warming stream temperatures and habitat degradation. The purpose of this assessment was to determine the impacts that projected future land use and climate changes might have on the condition of stream habitat to support self-sustaining brook trout populations. The study region encompassed the historic native range of brook trout, which includes the northeastern states and follows the Appalachian Mountains south to Georgia, where the distribution is limited to higher elevation streams with suitable water temperatures. Relationships between recent observations of brook trout and...
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Putting the Sampling Design to Work: Enhancing Species Monitoring Programs in the Face of Climate Change
Studying the impacts of climate on important ecological responses is a recent priority of monitoring programs throughout the Northeast. Established sampling protocols for data collection, whether to inform estimates of species abundance or occupancy, were designed to evaluate the effects of non-climate stressors (e.g., habitat conversion) and related management actions. Traditional modeling approaches may not accurately identify important relationships between species and climate nor elicit useful information on how these species will be impacted by climate change. Management decisions based on these traditional modeling approaches could have negative and unintended consequences on species and habitat conservation....
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Latitudes and longitudes for 45 sites samples for flathead catfish population genetic analyses.
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