Dennis Cocherell

Dennis Cocherell
Lab Manager
Staff Research Associate



B.S. Conservation Biology, University of California, Davis. Wildlife and Fish Conservation Biology (2005)

Research Interests:

As Professor Fangue’s laboratory manager I have the opportunity to work with multidisciplinary research teams to understand animal’s physiological specializations. My current research focuses on native anadromous and freshwater fishes. For example some of the current projects I am managing include: salmon and sturgeon swimming performance and behavior near unscreened water diversions and fish protection screens, the predictive value of temperature and salinity for the distribution of fishes in regulated systems, and how temperature affects the physiology of hardhead minnows. Other research interests cover a wide breadth of topics such as: stress responses and recovery in sturgeon utilizing fishways; environmental requirements of native fishes for conservation efforts; physiological ecology (including bioenergetics and osmoregulation); effects of pulsed-flows in altered river systems (fish distribution, physiology, behavior, and movements); salmonids use of submerged floodplain vegetation as hydraulic shields; fish screens, louvers, and deterrent devices.

Selected Publications:

Baird SE, Steel AE, Cocherell DE, Cech Jr JJ, Fangue NA. Native Chinook salmon Oncorhynchus tshawytscha and non‐native brook trout Salvelinus fontinalis prefer similar water temperatures. J Fish Biol. 2018;93:1000–1004.

Poletto, J.B., D.E. Cocherell, N. Ho, J.J. Cech Jr., A.P. Klimley, and N.A. Fangue.  (2018). The effect of size on juvenile green sturgeon (Acipenser medirostris) behavior near water-diversion fish screens. Environmental Biology of Fishes, 101(1): 67-77.

Poletto JB, Cocherell DE, Baird SE, Nguyen TX, Cabrera-Stagno V, Farrell AP, Fangue NA. (2017). Unusual aerobic performance at high temperatures in juvenile Chinook salmon, Oncorhynchus tshawytscha.  Conservation Physiology, 5(1): cow067

Poletto, J.B., D.E. Cocherell, T.D. Mussen, A. Ercan, H. Bandeh, M.L. Kavvas, J.J. Cech Jr., and N.A. Fangue. (2015). Fish protection devices at unscreened water diversions can reduce entrainment: Evidence from behavioral laboratory investigations.  Conservation Physiology, 3 (1): doi: 10.1093/conphys/cov040

Fangue, N. A., Cocherell, D.E., La Luz, F., Cech Jr, J. J., & Thompson, L. C. (2015). Juvenile and adult hardhead Mylopharodon conocephalus oxygen consumption rates: effects of temperature and swimming velocity. Environmental Biology of Fishes, 98(2), 585-596.

Mussen, T. D., Cocherell, D.E., Patton, O., Jauregui, D., Ercan, A., Bandeh, H., D. Meier, S. Thomas, M.L. Kavvas, J.J. Cech Jr. & Fangue, N. A. (2015). Modified Water Diversion Structures Can Behaviorally Deter Juvenile Chinook Salmon from Entrainment. Transactions of the American Fisheries Society, 144(5), 1070-1080.

Poletto, J.B., Cocherell, D.E., Mussen, T.D., Ercan, A., Bandeh, H., Kavvas, M.L., Cech, J.J. Jr., and Fangue, N.A. (2014). Efficacy of a sensory deterrent and pipe modifications in decreasing entrainment of juvenile green sturgeon (Acipenser medirostris) at unscreened water diversions. Conservation Physiology 2, doi:10.1093/conphys/cou056

Verhille, C.E., Poletto, J.B., Cocherell, D.E., DeCourten, B., Baird, S., Cech, J.J. Jr., and Fangue, N.A. (2014). Larval green and white sturgeon swimming performance in relation to water diversion flows. Conservation Physiology 2, doi:10.1093/conphys/cou031.

T.D. Mussen, D.E.Cocherell, J.B. Poletto, J.S. Reardon, Z. Hockett, A. Ercan, H. Bandeh, M.L. Kavvas, J.J. Cech Jr, N.A. Fangue (2014) Unscreened Water-Diversion Pipes Pose an Entrainment Risk to the Threatened Green Sturgeon, Acipenser medirostris. PLoS ONE 9(1): e86321. doi:10.1371/journal.pone.0086321

J.B. Poletto, D.E. Cocherell, N. Ho, J.J. Cech Jr., A. P. Klimley, N.A. Fangue (2014) Juvenile green sturgeon (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) behavior near water-diversion fish screens: experiments in a laboratory swimming flume. Canadian Journal of Fisheries and Aquatic Sciences, 71:1030-1038, 10.1139/cjfas-2013-0556

T.D. Mussen, O. Patton, D.E. Cocherell, A. Ercan, H. Bandeh, M.L. Kavvas, J.J. Cech, Jr., N.A. Fangue (2014) Can behavioral fish-guidance devices protect juvenile Chinook salmon, Oncorhynchus tshawytscha, from entrainment into unscreened water-diversion pipes? Canadian Journal of Fisheries and Aquatic Sciences. Published online 24 April 2014, DOI 10.1139/cjfas-2013-0601. 

E.A. Miller, H. E. Froehlich, D. E. Cocherell, M. J. Thomas, J. J. Cech, A. P. Klimley, and N.A. Fangue (2013) Effects of acoustic tagging on juvenile Green Sturgeon incision healing, swimming performance, and growth. Environmental Biology of Fishes [online serial] DOI: 10.1007/s10641-013-0167-x.

D.E., Cocherell, N.A. Fangue, A. P. Klimley, J.J. Cech Jr. Temperature preferences of hardhead Mylopharodon conocephalus and rainbow trout Oncorhynchus mykiss in an annular chamber. Environ Biology Fishes (2013) doi:10.1007/s10641-013-0185-8

J.B. Poletto, D.E. Cocherell, A.P. Klimley, J.J. Cech Jr., N.A. Fangue (2013) Behavioural salinity preferences of juvenile green sturgeon Acipenser medirostris acclimated to fresh water and full-strength salt water. Journal of Fish Biology, Vol 82, 2; 671–685

T.D. Mussen, D.E. Cocherell, Z. Hockett, A. Ercan, H. Bandeh, M. L. Kavvas, J. J. Cech Jr. & N.A. Fangue (2013)  Assessing Juvenile Chinook Salmon Behavior and Entrainment Risk near Unscreened Water Diversions: Large Flume Simulations. Transactions of the American Fisheries Society, Vol 142, 1;130-142

R.C. Kaufman, R. Coalter, N.L. Nordman, D.E. Cocherell, J.J. Cech Jr, L.C. Thompson, N.A. Fangue (2013) Effects of temperature on hardhead minnow (Mylopharodon conocephalus) blood-oxygen equilibria. Environmental Biology of Fishes, 96:1389–1397

D.E. Cocherell, A.Kawabata,  D.W. Kratville, S.A. Cocherell, R.C. Kaufman, E.K. Anderson, Z.Q. Chen, H. Bandeh,  M.M. Rotondo, R. Padilla, R. Churchwell, M.L. Kavvas,  J.J. Cech Jr (2011) Passage performance and physiological stress response of adult white sturgeon ascending a laboratory fishway. Journal of Applied Ichthyology, Vol 27, 2; 327–334

S.A. Cocherell, S.N. Chun, D.E. Cocherell, L.C. Thompson, A.P. Klimley, J. J. Cech Jr (2012) A lateral-displacement flume for fish behavior and stranding studies during simulated pulsed flows. Environmental Biology of Fishes Vol 93 1: 143-150

Cocherell S.A., D.E. Cocherell, G.J. Jones, JB. Miranda, L.C. Thompson, J. J. Cech Jr., and A. P. Klimley (2011) Rainbow trout Oncorhynchus mykiss energetic responses to pulsed flows in the American River, California, assessed by electromyogram telemetry. Environmental Biology Fishes, 90:29–41

Chun, S.N., S.A. Cocherell, D.E. Cocherell, J.B. Miranda, G.J. Jones, J. Graham, A.P. Klimley, L.C. Thompson, and J.J. Cech Jr (2011) Displacement, velocity preference, and substrate use of three native California stream fishes in simulated pulsed flows. Environmental Biology Fishes 90:43–52

Katzman S.M., J. Greathouse, J.M. Roessig, J. Graham, D.E. Cocherell, and J.J. Cech Jr (2010) Water velocity preferences of Coho Salmon during the parr-smolt transformation. Environmental Biology Fishes, 88:79–84


Selected Presentations:

  1. Cocherell. 2014. Physiological tools for guiding native fish management near hydroelectric power generation facilities: a case study of hardhead minnows. 48th Annual Conference of the California-Nevada Chapter of the American Fisheries Society Sacramento, CA.

  2. Cocherell. 2011. Green Sturgeon Experiments with Screens, Louvers, and Potential Enhancements to Fish Protection Devices: Small-Scale Flume Simulations. 45th Annual Cal-Neva Conference Lake Natoma Inn, Folsom, CA.

  3. Cocherell. 2007. Using an Annular, Laboratory Gradient to Determine Preferred Temperatures of Adult Fishes. American Fisheries Society California annual meeting, San Francisco, CA.

  4. Cocherell. 2007. Juvenile Chinook Salmon Use of Sandbar Willows in a Large-scale, Simulated Floodplain: Microhabitat Selection and Energetics. Riparian Habitat Joint Venture Conference.

  5. Cocherell. 2006. Adult white sturgeon passage behavior, swimming performance, passage efficiency, and stress responses.  Bioengineering Symposium, 40th Annual American Fisheries Society California-Nevada Chapter Conference, San Luis Obispo, CA.