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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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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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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.
Abstract (from http://www.tandfonline.com/doi/abs/10.1080/00028487.2012.734892#.VDw7ExYXNyg): Predicting the distribution of native stream fishes is fundamental to the management and conservation of many species. Modeling species distributions often consists of quantifying relationships between species occurrence and abundance data at known locations with environmental data at those locations. However, it is well documented that native stream fish distributions can be altered as a result of asymmetric interactions between dominant exotic and subordinate native species. For example, the naturalized exotic Brown Trout Salmo trutta has been identified as a threat to native Brook Trout Salvelinus fontinalis in the eastern...
Poikilothermic animals comprise most species on Earth and are especially sensitive to changes in environmental temperatures. Species conservation in a changing climate relies upon predictions of species responses to future conditions, yet predicting species responses to climate change when temperatures exceed the bounds of observed data is fraught with challenges. We present a physiologically guided abundance (PGA) model that combines observations of species abundance and environmental conditions with laboratory-derived data on the physiological response of poikilotherms to temperature to predict species geographical distributions and abundance in response to climate change. The model incorporates uncertainty in...
Categories: Publication; Types: Citation
Abstract (from http://www.tandfonline.com/doi/abs/10.1080/00028487.2014.963256#.VRQIaY7F8qY): The Brook Trout Salvelinus fontinalis is an important species of conservation concern in the eastern USA. We developed a model to predict Brook Trout population status within individual stream reaches throughout the species’ native range in the eastern USA. We utilized hierarchical logistic regression with Bayesian estimation to predict Brook Trout occurrence probability, and we allowed slopes and intercepts to vary among ecological drainage units (EDUs). Model performance was similar for 7,327 training samples and 1,832 validation samples based on the area under the receiver operating curve (∼0.78) and Cohen's kappa statistic...
Climate change is expected to result in widespread changes in species distributions (e.g., shifting, shrinking, expanding species ranges; e.g., Parmesan and Yohe 2003), especially for freshwater fish species (Heino et al. 2009). Although anglers and other resource users could be greatly affected by changes in species distributions, predicted changes are rarely reported in ways that can be easily understood by the general public. In contrast, climate science that more directly affects human welfare or livelihoods is often more readily communicated to the general public because it is of greater concern or closely related to everyday life. Read More at http://news.fisheries.org/translating-climate-change-effects-into-everyday-language-an-example-of-more-driving-and-less-angling/.
Estimating relative abundance is critical for informing conservation and management efforts and for making inferences about the effects of environmental change on populations. Freshwater fisheries span large geographic regions, occupy diverse habitats and consist of varying species assemblages. Monitoring schemes used to sample these diverse populations often result in populations being sampled at different times and under different environmental conditions. Varying sampling conditions can bias estimates of abundance when compared across time, location and species, and properly accounting for these biases is critical for making inferences. We develop a joint species distribution model (JSDM) that accounts for varying...
Categories: Publication; Types: Citation
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The number of fish collected in routine monitoring surveys often varies from year to year, from lake to lake, and from location to location within a lake. Although some variability in fish catches is expected across factors such as location and season, we know less about how large-scale disturbances like climate change will influence population variability. The Laurentian Great Lakes in North America are the largest group of freshwater lakes in the world, and they have experienced major changes due to fluctuations in pollution and nutrient loadings, exploitation of natural resources, introductions of non-native species, and shifting climatic patterns. In this project, we analyzed established long-term data about...
The number of fish collected in routine monitoring surveys often varies from year to year, from lake to lake, and from location to location within a lake. Although some variability in fish catches is expected across factors such as location and season, we know less about how large‐scale disturbances like climate change will influence population variability. The Laurentian Great Lakes in North America are the largest group of freshwater lakes in the world, and they have experienced major changes due to fluctuations in pollution and nutrient loadings, exploitation of natural resources, introductions of non‐native species, and shifting climatic patterns. In this project, we analyzed established long‐term data about...
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This dataset provides the microsatellite genotypes for 466 flathead catfish collected in Pennslyvania rivers for an analysis of population genetic structuring of introduced popualtions. Also included is the spatial location of sample sites.
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This dataset includes microsatellite genotypes for 137 flathead catfish from the Susquehanna River and Delaware River basins in Pennslyvania and Maryland, USA. Each individual was genotyped at 13 loci. Additional information about sex, capture date, and size are also provided for most individuals.
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This data release presents calculated accumulated wastewater (ACCWW, as a percent of total streamflow) values for 43 National Hydrologic Dataset Version 2.1 (NHDPlus V2.1) stream segments coinciding with long-term smallmouth bass sampling locations (Table 1) in the Shenandoah River Watershed (encompassing parts of Virginia and West Virginia, USA). Values are calculated for quarter-year (Quarter 1 [Q1], January - March; Quarter 2 [Q2], April - June; Quarter 3 [Q3], July-September; Quarter 4 [Q4], October-December) time scales (Table 2) and annual time scales (Table 3) for years 2000 to 2018. Estimates at a stream segment represent the combined total upstream wastewater discharges as well as direct discharges into...
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Fisheries managers in Midwestern lakes and reservoirs are tasked with balancing multiple management objectives to help maintain healthy fish populations across a landscape of diverse lakes. As part of this, managers monitor fish growth and survival. Growth rates in particular are indicators of population health, and directly influence the effectiveness of regulations designed to protect spawning fish or to promote trophy fishing opportunities. Growth, combined with reproduction and survival, also determines the amount of fish biomass available for harvest, known as population production. Changing water temperatures can influence growth and production of managed fish species in multiple complex ways, increasing the...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0022169414003990#): Water temperature is a fundamental property of river habitat and often a key aspect of river resource management, but measurements to characterize thermal regimes are not available for most streams and rivers. As such, we developed an artificial neural network (ANN) ensemble model to predict mean daily water temperature in 197,402 individual stream reaches during the warm season (May-October) throughout the native range of brook trout Salvelinus fontinalis in the eastern U.S. We compared four models with different groups of predictors to determine how well water temperature could be predicted by climatic, landform, and land cover...
Abstract (from NRC Research Press): Lakes respond heterogeneously to climate, with implications for fisheries management. We analyzed walleye (Sander vitreus) recruitment to age-0 in 359 lakes in Wisconsin, USA, to (i) quantify the relationship between annual water temperature degree days (DD) and walleye recruitment success and (ii) identify the influence of lake characteristics — area, conductivity, largemouth bass (Micropterus salmoides) catch rates, and mean DD — on this relationship. The relationship between walleye recruitment and annual DD varied among lakes and was not distinguishable from zero overall (posterior mean = −0.11, 90% CI = −0.34, 0.15). DD effects on recruitment were negative in 198 lakes (55%)...
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Human impacts occurring throughout the DOI Northeast Climate Science Center, including urbanization, agriculture, and dams, have multiple effects on streams in the region which support economically valuable stream fishes. Changes in climate are expected to lead to additional impacts in stream habitats and fish assemblages in multiple ways, including changing stream water temperatures. To manage streams for current impacts and future changes, managers need region-wide information for decision-making and developing proactive management strategies. Our project met that need by integrating results of a current condition assessment of stream habitats based on fish response to human land use, water quality impairment,...
map background search result map search result map Understanding the Varying Responses of Fish Populations to Future Climate Projected Vulnerability of Brook Trout to Climate and Land Use Changes in the Eastern U.S. (Regional Assessment) FishTail: A Tool to Inform Conservation of Stream Fish Habitats in the Northeast Quantifying the Impacts of Climate Change on Fish Growth and Production to Enable Sustainable Management of Diverse Inland Fisheries Population genetic data for flathead catfish from the Susquehanna and Delaware River basins in Pennsylvania and Maryland, USA Putting the Sampling Design to Work: Enhancing Species Monitoring Programs in the Face of Climate Change Accumulated wastewater calculations for smallmouth bass sampling sites in the Shenandoah River Watershed, USA Microsatellite genotypes for flathead catfish used for analysis of genetic structuring in Pennsylvania rivers Locations of sites sampled for flathead catfish used for analysis of genetic structuring in Pennsylvania rivers Accumulated wastewater calculations for smallmouth bass sampling sites in the Shenandoah River Watershed, USA Microsatellite genotypes for flathead catfish used for analysis of genetic structuring in Pennsylvania rivers Locations of sites sampled for flathead catfish used for analysis of genetic structuring in Pennsylvania rivers Population genetic data for flathead catfish from the Susquehanna and Delaware River basins in Pennsylvania and Maryland, USA Understanding the Varying Responses of Fish Populations to Future Climate Quantifying the Impacts of Climate Change on Fish Growth and Production to Enable Sustainable Management of Diverse Inland Fisheries Projected Vulnerability of Brook Trout to Climate and Land Use Changes in the Eastern U.S. (Regional Assessment) Putting the Sampling Design to Work: Enhancing Species Monitoring Programs in the Face of Climate Change FishTail: A Tool to Inform Conservation of Stream Fish Habitats in the Northeast