Browsing by Author "University of Minnesota Dr. Hansen Research Team"
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Item Data In Support Of Accounting For Spatio-Temporal Variation In Catachability In Joint Species Distribution Models(2022-04-21) North, Joshua S.; Schliep, Erin M.; Hansen, Gretchen J.A.; Kundel, Holly; Custer, Christoper A.; McLaughlin, Paul; joshuanorth@mail.missouri.edu; North, Joshua S.; University of Minnesota Dr. Hansen Research TeamFish data on six species (black crappie (Pomoxis nigromaculatus), bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), northern pike (Esox lucius), walleye (Sander vitreus), and yellow perch (perca flavescens)) caught in gill nets and trap nets between 2000 and 2019 during Minnesota Department of Natural Resources (MNDNR) fisheries surveys done in the months of June through September. Fish catch and effort (number of nets set overnight) comes from over 1,000 Minnesota lakes. In addition to fisheries data, we included additional information concerning lake characteristics, predicted water temperature, and watershed land use. Lake area and maximum depth were obtained from MNDNR public databases. Watershed land use was calculated using the 2016 National Land Cover Database. Water clarity, which is described by annual lake-specific median values derived from remotely sensed Secchi depth courtesy of Max Gilnes. Lastly, water temperatures simulated with the general lake model were also included. Data is now being released as part of the publication process related to the paper that references this data; which is listed below.Item Data in Support of Predicting climate change impacts on poikilotherms using physiologically guided species abundance models(2022-07-14) Schliep, Erin M; North, Joshua S; Kundel, Holly; Custer, Christopher A; Ruzich, Jenna K; Hansen, Gretchen J A; ghansen@umn.edu; Hansen, Gretchen J A; University of Minnesota Dr. Hansen Research TeamFish catch and effort data for three species caught in gill nets and trap nets between 1988 and 2019 as part of Minnesota Department of Natural Resources (MNDNR) fisheries surveys conducted during the summer and early fall are included from over 1,300 Minnesota lakes. The three fish species included are: bluegill (Lepomis marochirus) a warm-water adapted species, yellow perch (Perca flavescens) a cool-water adapted species, and cisco (Coregonus artedi) a cold-water adapted species. Additional data concerning lake characteristics and surrounding land cover were also included. Mean July lake surface temperature was calculated using simulated daily water temperatures. Watershed land use including agricultural, barren, forest, grass, shrub, urban, and wetland cover, was determined using the 2016 National Land Cover Database. Secchi, a measure of water clarity was calculated from remotely sensed Secchi depth courtesy of Max Glines. Lastly, lake area and maximum depth were obtained from MNDNR public databases.Item Data in Support of Widespread declines in walleye recruitment following zebra mussel invasion in Minnesota lakes(2023-04-26) Kundel, H; Hansen, Gretchen J A; kunde058@umn.edu; Kundel, H; University of Minnesota Dr. Hansen Research TeamInvasive zebra mussels (Dreissena polymorpha) alter lake ecosystems and can negatively affect first-year growth of walleye (Sander vitreus), potentially lowering walleye overwinter survival and recruitment success. Zebra mussel effects also vary among lakes, and walleye resilience to the effects of zebra mussels may vary depending on lake characteristics (e.g., depth, clarity) or fish community composition. To test these hypotheses, we used data from 1,438 surveys across 348 lakes collected between 1993 and 2019 to measure walleye recruitment, defined as relative abundance of age-0 walleye in their first fall. We fitted Bayesian hierarchical models to quantify the effects of zebra mussels on walleye recruitment while accounting for the effects of lake temperature, surface area, and water clarity. A before-after-control-impact (BACI)-like design was used to account for potential changes in recruitment due to factors other than zebra mussel invasion. Age-0 walleye recruitment to their first fall was ~41% lower (95% credible interval of 38 - 44%) in lakes containing zebra mussels compared to uninvaded lakes. Invaded lakes had higher recruitment prior to zebra mussel invasion than lakes that remain uninvaded. Conversely, walleye recruitment increased slightly (7% (95% credible interval 2 - 11%)) in lakes without zebra mussels over the same time period. Walleye recruitment was higher in larger lakes and lakes with lower water clarity. Water temperature, as indexed by degree days (base 5 °C), did not affect walleye recruitment. Our results demonstrate negative effects of zebra mussel invasion on walleye population dynamics at a landscape scale.