Dr. Timothy Walsworth
Watershed Sciences / Ecology Center
Assistant Professor
Contact Information
Office Hours: By AppointmentOffice Location: BNR 283
Phone: (435) 797-0874
Email: timothy.walsworth@usu.edu
Additional Information:
Teaching Interests
I teach undergraduate courses on Fish Ecology, Conservation, and Management (WATS 3100 and 3110), in which students learn how fishes interact with their environment, how we manage different types of fisheries, and why effective and sustainable fisheries management is critically important not just for ecosystems, but also for human economies and societies.
Additionally, I teach a graduate level class (WATS 6460) focusing on dynamic models and how they can be used to understand population dynamics and inform management decisions. Students learn to design and fit custom dynamic models to data, and then use these models in a simulation framework to assess the impact of alternative management and conservation actions.
Research Interests
My lab's research examines how fish populations, aquatic communities and socio-ecological systems respond to and deal with environmental change, management actions and uncertainty. We apply quantitative modeling approaches to characterize past dynamics and project future dynamics under uncertain conditions, providing valuable information to managers and decision makers. Our research spans a broad range of ecosystems and species, from endangered non-game fishes in the American southwest, to commercially important salmon in Alaska.
Awards
Graduate Mentor of the Year, 2025
Quinney College of Natural Resources
Undergraduate Research Mentor of the Year, 2021
Quinney College of Natural Resources
Publications | Fact Sheets
- James, C., Becker, K., Hotaling, S., Chandrasekaran, A., Walsworth, T., Belmont, P., (2025). Post-wildfire erosion and sedimentation: An escalating threat of Utah’s fisheries. USU Extension
An asterisk (*) at the end of a publication indicates that it has not been peer-reviewed.
Publications | Journal Articles
Academic Journal
- Lamborn, C., Ohlberger, J., Walsworth, T., Westley, P.A, Cunningham, C.J, Wynsma, S., Smith, J., (2025). A synthesis of factors related to trends in abundance and demography of Alaska Chinook salmon (Oncorhynchus tshawytscha, Salmonidae): Implications for research, management, and policy. Fish and Fisheries, 26, 520-532. doi: 10.1111/faf.12895
- Lepak, J.M, Hansen, A.G, Johnson, B.M, Battige, K., Cristan, E.T, Farrell, C.J, Pate, W.M, Rogers, K.B, Treble, A.J, Walsworth, T., (2025). Cyclical, multi-trophic-level responses to a volatile, introduced forage fish: Learning from four decades of food web observation to inform management. Fisheries, vuae013. doi: 10.1093/fshmag/vuae013
- Walsworth, T., Hansen, A.G, Lepak, J.M, (2025). Alternating ecosystem states driven by an invasive fish in a life-history intraguild predation system. Canadian Journal of Fisheries and Aquatic Sciences, doi: doi.org/10.1139/cjfas-2025-001
- González Ortiz, A.A, Walsworth, T., Hammill, E., Palomares, M.L, Pauly, D., Atwood, T., (2025). Fisheries disrupt marine nutrient cycles through biomass extraction. Communications Earth & Environment, 6:1, doi: 10.1038/s43247-025-02218-z
- Goodrum, G.C, Hawkins, C.P, Walsworth, T., Null, S., (2025). Predicting road‐crossing passability for river connectivity analysis. River Research and Applications, doi: 10.1002/rra.4434
- Fadlovich, R., Landom, K., Walsworth, T., (2025). Selectivity of invasive species suppression efforts influences control efficacy. Journal of Applied Ecology, doi: 10.1111/1365-2664.14856
- Turney, E.K, Goodrum, G.C, Saunders, W.C, Walsworth, T., Null, S., (2025). Comparing commonly used aquatic habitat modeling methods for native fish. Ecological Modelling, 499, doi: 10.1016/j.ecolmodel.2024.110909
- Wallace, E., Walsworth, T., (2024). Identifying control intensities to overcome aquatic invader resilience across a range of ecosystem sizes. Journal of Applied Ecology, 61:11, 2605-2615. doi: 10.1111/1365-2664.14792
- Conner, M., Landom, K., Walsworth, T., Wilkison, R.A, Fonken, D., Thompson, P., Keleher, C., Franklin, R., (2024). Detecting bias in abundance estimates of spawning fish from closed-capture models using remote and physical capture data. North American Journal of Fisheries Management, 44:5, 1025-1040. doi: 10.1002/nafm.11031
- Walsworth, T., Fadlovich, R., Fonken, D., Heinle, K.B, May, E., Rousseau, S., Wallace, E., Landom, K., (2024). Interactions between runoff volume, timing, and annual temperatures shape migration phenology of a threatened adfluvial sucker. Ecology of Freshwater Fish, 33:4, doi: 10.1111/eff.12791
- Glassic, H.C, Junker, J.R, Guy, C.S, Tronstad, L.M, Briggs, M.A, Albertson, L.K, Lujan, D.R, Brenden, T.O, Walsworth, T., Koel, T.M, (2024). An Invasive Predator Substantially Alters Energy Flux Without Changing Food Web Functional State or Stability. Aquatic Conservation: Marine and Freshwater Ecosystems, 34:9, doi: 10.1002/aqc.4240
- Feldman, E.V, Walsworth, T., Kettenring, K., (2024). Native species identity drives plant community growth and biotic resistance. Applied Vegetation Science, 27:3, doi: 10.1111/avsc.12808
- Glassic, H.C, Chagaris, D.D, Guy, C.S, Tronstad, L.M, Lujan, D.R, Briggs, M.A, Albertson, L.K, Brenden, T.O, Walsworth, T., Koel, T.M, (2024). Yellowstone Cutthroat Trout Recovery in Yellowstone Lake: Complex Interactions Among Invasive Species Suppression, Disease, and Climate Change. Fisheries, 49:2, 55-70. doi: 10.1002/fsh.10998
- Baldock, J.R, Al-Chokhachy, R., Walsworth, T., Walters, A., (2023). Redd superimposition mediates the accuracy, precision, and significance of redd counts for cutthroat trout. Canadian Journal of Fisheries and Aquatic Sciences, 80:5, 825-839. doi: 10.1139/cjfas-2022-0267
- Solokas, M.A, Feiner, Z.S, Al-Chokachy, R., Budy, P., DeWeber, J.T, Sarvala, J., Sass, G.G, Tolentino, S.A, Walsworth, T., Jensen, O.P, (2023). Shrinking body size and climate warming: Many freshwater salmonids do not follow the rule. Global Change Biology, 29:9, 2478-2492. doi: 10.1111/gcb.16626
- Fonken, D., Conner, M., Walsworth, T., Thompson, P., (2022). Benefits of stocking fewer, but larger individuals with implications for native fish recovery. Canadian Journal of Fisheries and Aquatic Sciencesja, doi: 10.1139/cjfas-2022-007
An asterisk (*) at the end of a publication indicates that it has not been peer-reviewed.
Publications | Other
An asterisk (*) at the end of a publication indicates that it has not been peer-reviewed.