Tyler Wagner, Ph.D.
- Ph.D., Michigan State University (2006)
- M.S., University of Idaho (2000)
- B.S., University of Idaho (1999)
Multiple spatial-scale assessment of aquatic resources
Quantitative Methods in Ecology
The Ecological Society of America
American Fisheries Society
North American Lake Management Society
Recent Research/Educational Projects:
Predicting population responses to climate change requires an understanding of how population dynamics vary over space and time. Although variability has historically been viewed as an impediment to understanding population responses to ecological changes, it can provide an important signal, rather than just being viewed as noise. In this project, we will build upon recently completed analyses of fish population data in the Great Lakes basin to help predict how spatial and temporal variation in fish populations may respond to climate change and other important drivers. We suggest that shifting variance structure can be indicative of population-level responses to climate change. Our proposed research will help elucidate the extent to which quantifiable responses in spatial and temporal variability occur in different forms of fish population data.
Fish Community Assessment in the Eastern Rivers and Mountains Network and Integration with Existing Monitoring Data
The National Park Service (NPS) has initiated a long-term ecological monitoring program, known as “Vital Signs Monitoring”, to provide the minimum infrastructure to allow more than 270 national park system units to identify and implement long-term monitoring of their highest-priority measurements of resource condition. The Eastern Rivers and Mountains Network (ERMN) includes nine parks in New York, New Jersey, Pennsylvania, and West Virginia which together encompass nearly 91,000 ha of land area and more than 600 stream and river miles within the parks’ authorized boundaries. A primary objective of the ERMN monitoring program is to evaluate status and trends in the condition of tributary watersheds flowing into and through member parks. Currently, the monitoring of fish communities is not part of the monitoring program. Consequently, methodology is needed to estimate the current condition of fish communities in ERMN wadeable streams in a rigorous and repeatable manner. Estimates of the current fish community’s condition at ERMN stream sites will complement data collected on an annual basis (i.e., Vital Signs Monitoring) and enable an integrated measure of ecosystem condition that can be monitored over time. The specific objectives of this study are to: (1) characterize fish communities in selected ERMN stream reaches, and (2) combine fish community data with existing monitoring data (e.g., macroinvertebrates) to provide an integrated measure of stream ecological condition.
DeWeber, J.T and T. Wagner. 2015. Predicting brook trout occurrence in stream reaches throughout their native range in the eastern United States. Transactions of the American Fisheries Society 144:11-24.
Midway, S., T. Wagner, B. H. Tracy, G. M. Hogue, and W.C. Starnes. Accepted. Evaluating changes in stream fish species richness over a 50-year time-period within a landscape context. Environmental Biology of Fishes.
Wagner, T., and S. R. Midway. 2014. Modeling spatially varying landscape change points in species occurrence thresholds. Ecosphere 5(11):145. http://dx.doi.org/10.1890/ES14-00288.1
DePasquale, C., T. Wagner, G.A. Archard, B. Ferguson, and V.A. Braithwaite. In press. Learning rate and temperament in a high predation risk environment. Oecologia.
Kepler, M.V., T. Wagner, and J.A. Sweka. 2014. Comparative bioenergetics modeling of two Lake Trout morphotypes. Transactions of the American Fisheries Society 143:1592–1604.
Filstrup, C.T., T. Wagner, P.A. Soranno, E.H. Stanley, C.A. Stow, K.E. Webster, and J. A. Downing. 2014. Regional variability among nonlinear chlorophyll-phosphorus relationships in lakes. Limnology and Oceanography 59:1691-1703.
Perles, S.J., T. Wagner, B.J. Irwin, D.R. Manning, K.K. Callahan, and M.R. Marshall. 2014. Evaluation of a regional monitoring program's statistical power to detect temporal trends in forest health indicators. Environmental Management 54:641-655.
Deweber, J.T. and T. Wagner. 2014. A regional neural network model for predicting mean daily river water temperature. Journal of Hydrology 517:187-200.
Midway, S.M., T. Wagner, and B. Tracy. 2014. A hierarchical community occurrence model for North Carolina stream fish. Transactions of the American Fisheries Society 143:1348-1357.
Lottig, N.R., T. Wagner, E. Norton Henry, K. Spence Cheruvelil, K.E. Webster, et al. 2014. Long-term citizen-collected data reveal geographical patterns and temporal trends in lake water clarity. PLoS ONE 9(4): e95769. doi:10.1371/journal.pone.0095769
Levy, O., B.A. Ball, B. Bond-Lamberty, K.S. Cheruvelil, A.O. Finley, N. Lottig, S.W. Punyasena, J. Xiao, J. Zhou, L.B. Buckley, C.T. Filstrup, T. Keitt, J.R. Kellner, A.K. Knapp, A.D. Richardson, D. Tcheng, M. Toomey, R. Vargas, J.W. Voordeckers, T. Wagner, J.W. Williams. 2014. Approaches to advance scientific understanding of macrosystems ecology. Frontiers in Ecology and the Environment 12:15-23.
Deweber, J.T., Y., Tsang, D.M. Krueger, J.B. Whittier, T. Wagner, D.M. Infante, and G. Whelan. 2014. Importance of understanding landscape biases in USGS gage locations: Implications and solutions for managers. Fisheries 39:155-163.
Wagner, T., J.T. Deweber, J. Detar, D. Kristine, and J.A. Sweka. 2014. Spatial and temporal dynamics in Brook Trout density: implications for population monitoring. North American Journal of Fisheries Management 34:258-269.
Detar, J. D. Kristine, T. Wagner, and T. Greene. 2014. Evaluation of catch-and-release regulations on Brook Trout in Pennsylvania streams. North American Journal of Fisheries Management 34:49-56.
Soranno, P.A., K. Spence Cheruvelil, E. Bissell, M. Tate-Bremigan, J.A. Downing, C.E. Fergus, C. Filstrup, N.R. Lottig, E.N. Henry, E.H. Stanley, C.A. Stow, P.N. Tan, T. Wagner, and K.E. Webster. 2014. Cross-scale interactions: A conceptual framework for understanding multi-scaled cause-effect relationships in macrosystems. Frontiers in Ecology and the Environment 12:65-73.
Mollenhauer, R. T. Wagner, M.V. Kepler, J.A. Sweka. 2013. Fall and early winter movement and habitat use of wild brook trout. Transactions of the American Fisheries Society 142:1167-1178.
Wagner, T. B.J. Irwin, J.R. Bence, and D.B. Hayes. 2013. Detecting temporal trends in freshwater fisheries surveys: statistical power and the important linkages between management questions and monitoring objectives. Fisheries 38:309-319.
Wagner, T. , J.T. Deweber, J. Detar, and J.A. Sweka. 2013. Landscape-scale evaluation of asymmetric interactions between brown trout and brook trout using two-species occupancy models. Transactions of the American Fisheries Society 142:353-361.
Irwin, B. J., T. Wagner, J. R. Bence, M. V. Kepler, W. Liu, and D. B. Hayes. 2013. Estimating spatial and temporal components of variation for fisheries count data using negative binomial mixed models. Transactions of the American Fisheries Society 142:171-183.
Sweka, J. A., T. Wagner, J. Detar, and D. Kristine. 2012. Combining Field Data with Computer Simulations to Determine a Representative Reach for Brook Trout Assessment. Journal of Fish and Wildlife Management 3:209-222.
Rennie, M.D., M.P. Ebener, and T. Wagner. 2012. Can migration mitigate the effects of ecosystem change? Patterns of dispersal, energy acquisition and allocation in Great Lakes lake whitefish (Coregonus clupeaformis). Proceedings of the 10th Annual Coregonid Symposium. Advances in Limnology 63:455-476.
Wagner, T., D.R. Diefenbach, A.S. Norton, and S.A. Christensen. 2011. Using multilevel models to quantify heterogeneity in resource selection. Journal of Wildlife Management 75:1788-1796.
Wagner, T., P.A. Soranno, K.E. Webster, and K. Spence Cheruvelil. 2011. Landscape drivers of regional variation in the relationship between total phosphorus and chlorophyll in lakes. Freshwater Biology 56:1811-1824. doi:10.1111/j.1365-2427.2011.02621.x
Soranno, P.A., T. Wagner, S. Martin, L. McLean, L. Novitski,C. Provence, and A. Rober. 2011. Quantifying regional reference conditions for freshwater ecosystem management: A comparison of approaches and future research needs. Lake and Reservoir Management 27:138-148.
Wagner, T. and J.A. Sweka. 2011.Evaluation of hypotheses for describing temporal trends in Atlantic salmon parr densities in Northeast U.S. Rivers. North American Journal of Fisheries Management 31:340–351.
Soranno, P.A., K. Spence Cheruvelil, K.E. Webster, M.T. Bremigan, T. Wagner, and C.A. Stow. 2010. Freshwater Ecosystem Classification for Landscape-scale Management. BioScience 60:440-454.
Wagner, T. and 7 coauthors. 2010. Spatial and temporal dynamics of lake whitefish (Coregonus clupeaformis) health measures: linking individual-based indicators to a management-relevant endpoint. Journal of Great Lakes Research 36:121-134.
Wagner, T., C.S. Vandergoot, and J. Tyson. 2009. Evaluating the Power to Detect Temporal Trends in Fishery-Independent Surveys: A Case Study Based on Gillnets Set in the Ohio Waters of Lake Erie for Walleye. North American Journal of Fisheries Management 29:805-816.
Wagner, T., M.E. Benbow, T.O. Brenden, J. Qi, and R.C. Johnson. 2008. Buruli ulcer disease prevalence in Benin, West Africa: associations with land use/cover and the identification of disease clusters. International Journal of Health Geographics 7:25.
Wagner, T., P.A. Soranno, K. Spence Cheruvelil, B. Renwick, K. Webster, P. Vaux, and R. Abbitt. 2008. Quantifying sample biases of inland lake sampling programs in relation to lake surface area and land use/cover. Environmental Monitoring and Assessment 131-147.
Wagner, T., J.R. Bence, M.T. Bremigan, D.B. Hayes, and M.J. Wilberg. 2007. Regional trends in fish mean length at age: components of variance and the power to detect trends. Canadian Journal of Fisheries and Aquatic Sciences 64:968-978.
Wagner, T., M.T. Bremigan, K. Spence Cheruvelil, P.A. Soranno, N.N. Nate, and J.E. Breck. 2007. A multilevel modeling approach to assessing regional and local landscape features for lake classification and assessment of fish growth rates. Environmental Monitoring and Assessment 130:437-454.
Wagner, T. A.K. Jubar, and M.T. Bremigan. 2006. Can habitat alteration and spring angling explain black bass nest distribution and success? Transactions of the American Fisheries Society 135:843-852.
Wagner, T., D.B. Hayes, and M.T. Bremigan. 2006. Accounting for multilevel data structures in fisheries data using mixed models. Fisheries 31:180-187.
Congleton, J. L., and T. Wagner. 2006. Blood-chemistry indicators of nutritional status in juvenile salmonids. Journal of Fish Biology 69:473-790.
Zabel, R.W., T. Wagner, J.L. Congleton, S.G. Smith, and S.G. Williams. 2005. Survival and selection of migrating salmon from capture-recapture models with individual traits. Ecological Applications 15:1427-1439.
Wagner, T., and J.L. Congleton. 2004. Blood-chemistry correlates of nutritional condition, tissue damage, and stress in migrating juvenile chinook salmon (Oncorhynchus tshawytscha). Canadian Journal of Fisheries and Aquatic Sciences 61:1066-1074.
Wagner, T., J.L. Congleton, and D.M. Marsh. 2004. Smolt-to-adult return rates of juvenile chinook salmon transported through the Snake-Columbia River hydropower system, USA, in relation to densities of co-transported juvenile steelhead. Fisheries Research 68:259-270.