Technical Reports: Nonnative Fish Management

Nonnative Fish Management Strategies

Smallmouth bass

Stahli, J., K. R. Bestgen, and P. V. Badame. 2024. Enhancing the Smallmouth Bass Toolbox. Proposal to the USBR for Upper Basin Environmental Drought Mitigation (B2E) grant. 

Bestgen, K. R. 2018. Evaluate effects of flow spikes to disrupt reproduction of smallmouth bass in the Green River downstream of Flaming Gorge Dam. Final report to the Upper Colorado River Endangered Fish Recovery Program. Denver, Colorado. Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins. Larval Fish Laboratory Contribution 214.

Bestgen, K. R., and A. A. Hill. 2016. River regulation affects reproduction, early growth, and suppression strategies for invasive smallmouth bass in the upper Colorado River basin. Final report submitted to the Upper Colorado River Endangered Fish Recovery Program, Denver, Colorado. Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins. Larval Fish Laboratory Contribution 187.

Breton, A. R, D. L. Winkelman, K. R. Bestgen, and J. A. Hawkins. 2015. Population dynamics modeling of introduced smallmouth bass in the upper Colorado River basin. Final report to the Upper Colorado River Endangered Fish Recovery Program, Denver, Colorado. Larval Fish Laboratory Contribution 186.

Breton, A. R, D. L. Winkelman, J. A. Hawkins, and K. R. Bestgen. 2014. Population trends of smallmouth bass in the upper Colorado River basin with an evaluation of removal effects. Final report to the Upper Colorado River Endangered Fish Recovery Program, Denver, Colorado. Larval Fish Laboratory Contribution 169.

Fuller, M. 2009. Lower Yampa River Channel Catfish and Smallmouth Bass Control Program, Colorado, 2001-2006.

Hawkins, J., C. Walford, and A. Hill. 2009. Smallmouth bass control in the middle Yampa River, 2003-2007.

Badame, P.,et al, 2008. Smallmouth Bass (Micropterus dolomieu) Removal in the Middle Green River, Utah 2004-2006.

G. Haines and T. Modde. 2007. A review of smallmouth bass removal in Yampa Canyon, with notes on the simulated effort needed to reduce smallmouth bass in the Green River subbasin.

Bob D. Burdick. 2008. Removal of Smallmouth Bass and Four Other Centrarchid Fishes from the Upper Colorado and Lower Gunnison Rivers: 2004-2006

Northern pike

Zelasko, K. A., K. R. Bestgen, J. A. Hawkins, G. C. White. 2015. Abundance and population dynamics of invasive northern pike Esox lucius, Yampa River, Colorado, 2004–2010. Final Report to the Upper Colorado River Endangered Fish Recovery Program, Project 161b, Denver. Larval Fish Laboratory Contribution 185.

Bestgen, K. R., K. A. Zelasko, T. Eyre, C. Smith, G. C. White and M.T. Jones. 2020. Abundance estimation following increased removal verifies declining trend of northern pike in the Yampa River, Colorado. Final Report to the Upper Colorado River Endangered Fish Recovery Program, Denver. Larval Fish Laboratory Contribution 218.

Martin, L. M. and Wright, F. B.  Middle Yampa River Northern Pike and Smallmouth Bass Removal and Evaluation; Colorado Pikeminnow and Roundtail Chub Evaluation: 2004 – 2007.

Fitzpatrick, R.M. and D.L. Winkelman. 2009. Use of otolith elemental signatures in estimating sources of northern pike recruitment in the Yampa River, Colorado. Final Report Project 143 to the Upper Colorado River Endangered Fish Recovery Program.

S. Finney and G. Haines. 2008. Northern Pike Removal, Smallmouth Bass Monitoring, and Native Fish Monitoring in the Yampa River, Hayden to Craig Reach, 2004-2006.

L. Monroe and T. Hedrick. 2008. Northern Pike (Esox lucius) Control in the Middle Green River, Utah 2001-2006.

Christopher G. Hill. 2005. Dynamics of Northern Pike Spawning and Nursery Habitat in the Yampa River, Colorado. 

Hawkins, J.,et al, 2005. Northern pike management studies in the Yampa River, 1999-2002. Final report of Larval Fish Laboratory, Colorado State University, Fort Collins to Upper Colorado River Endangered Fish Recovery Program, U.S. Fish and Wildlife Service, Denver, Colorado.

Walleye

Thibedeau, I. A. 2025. Invasive Walleye Demographics and Predation on Rare Native Fish in the Upper Colorado River Basin. Master’s thesis, Colorado State University. Mountain Scholar. https://mountainscholar.org/items/29032cde-268b-4320-96b4-49b80f2f0bfe.

Shields, R. and J. Gaeta. 2022. Modeling Sterile Walleye (Sander vitreus) Stocking to Mitigate the Growth of Illegally Introduced Populations. Final Report to the Upper Colorado River Endangered Fish Recovery Program. Denver, Colorado. Utah Division of Wildlife Resources. Salt Lake City, Utah. Publication number 25-27.

Nonnative Fish Escapement

Hansen, A.G., C.J. Farrell and B.M. Johnson. 2023. Simulated effects of imperfect sterile sport fish stocking on persistence of fertile fish in new exploited populations. North American Journal of Fisheries Management.

Johnson, B.M., B. Wolf, and P.J. Martinez. 2014. Chemically Fingerprinting Nonnative Fish in Reservoirs. Final Report of Project C18/19 to the Upper Colorado River Endangered Fish Recovery Program.

Breton, A. R., J. A. Hawkins, K. R. Bestgen, D. L. Winkelman, and G. C. White. 2013. Escapement rates of translocated smallmouth bass (Micropterus dolomieu) from Elkhead Reservoir to the Yampa River. Final Report of Project 161 to the Upper Colorado River Endangered Fish Recovery Program.

Johnson, B.M.,et al, 2007. Stable Isotope Analysis of Centrarchid Concentration Areas.

Brunson, R.,et al, 2007. Evaluation of nonnative fish escapement from Starvation Reservoir

Miller.,et al, 2005. Elkhead Reservoir Escapement.

W. J. Miller and D. Laiho. 1997. Feasibility Evaluation of Non-Native Fish Control Structures.

DRAFT REPORT: Elkhead Dam/Reservoir Fish Separation Preliminary Design Report

Native Fish Response

Bestgen, K.R., K. A. Zelasko, E. R. Kluender, C. T. Smith, and M. T. Jones. 2026. Invasive predators overwhelm natural and re-regulated flow and temperature benefits and decimate native fish. Final report to the Upper Colorado River Endangered Fish Recovery Program. Denver, Colorado. Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins. Larval Fish Laboratory Contribution 234.

Breen, M.J. and M.T. Jones. 2019. Assessment of Larval Colorado Pikeminnow Presence and Survival in Low Velocity Habitats in the Middle Green River: 2009-2012. Final Report to the Upper Colorado River Endangered Fish Recovery Program. Denver, Colorado. Utah Division of Wildlife Resources. Salt Lake City, Utah. Publication number 19-05.

Skorupski, J. A., M. J. Breen, and L. Monroe. 2012. Native Fish Response to Nonnative Fish Removal from 2005-2008 in the Middle Green River, Utah. Utah Department of Natural Resources Final Report Project 144 to the Upper Colorado River Endangered Fish Recovery Program.

Bestgen, K.R.,et al, 2007. Native Fish Response To Removal Of Non-Native Predator Fish In the Yampa River, Colorado.

Bestgen, K.R.,et al, 2007. Non-native fish removal in the Green River, Lodore and Whirlpool Canyons, 2002-2006, and fish community response to altered flow and temperature regimes, and non-native fish expansion.

General Topics

Trammell, M.,et al, 2004. Nonnative cyprinid removal in the lower Green and Colorado rivers, Utah. UDWR publication 05-10.

Martinez, P.J., and N.P. Nibbelink. 2004. Colorado nonnative fish stocking regulation evaluation. Final Report of Colorado Division of Wildlife and Wyoming Geographic Information Science Center to Upper Colorado River Endangered Fish Recovery Program, Denver, Colorado.

Martinez, A.M. 2004. An Evaluation of Nonnative Fish Control Treatments in Ponds along the Colorado and Gunnison Rivers, 1996-2002

Tyus, H. and J. Saunders, III. 1996. Nonnative Fishes in the Upper Colorado River Basin and A Strategic Plan for Their Control.