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Sierra Nevada Bighorn
407 West Line St.
Bishop CA 93514
Dr. Tom Stephenson
Bio in Brief
Tom is a Senior Environmental Scientist with CDFW. He is the program leader for the Sierra Nevada Bighorn Sheep Recovery Program and the wildlife supervisor for the northern portion of CDFW's Inland Deserts Region. Prior to becoming the program leader, he was the bighorn sheep biologist for the Recovery Program. Tom is also an affiliate assistant professor with the University of Montana and Idaho State University. He received his B.S., M.S., and Ph.D. in wildlife biology from Colorado State University, Virginia Tech, and the University of Idaho, respectively. He was formerly a research wildlife biologist with the Alaska Department of Fish and Wildlife and director of the Kenai Moose Research Center, as well as an affiliate assistant professor with the University of Alaska, Fairbanks.
Key: P - Peer Reviewed Publication, D - Dissertation, PE - Peer Edited Publications, B - Book Chapters
- P - Monteith, K.L, T.R. Stephenson, , V. B. Bleich, Mary M. Conner, B.M. Pierce, and R. Terry Bowyer. Risk-sensitive allocation in seasonal dynamics of fat and protein reserves in a long-lived mammal. 2013. Journal of Animal Ecology. DOI: 10.1111/1365-2656.12016.
- P - Johnson, H. E., M.H. Hebblewhite, T.R. Stephenson, D.W. German, B.M. Pierce, V. B. Bleich. Evaluating apparent competition in limiting the recovery of an endangered ungulate. Oecologia. 171(1):295-307. doi: 10.1007/s00442-012-2397-6. Jan. 2013.
- P - Cahn, M. L., M. M. Connor, O. J. Schmitz, T. R. Stephenson, J. D. Wehausen and H. E. Johnson. Disease, Population Viability, and Recovery of Endangered Sierra Nevada Bighorn Sheep. The Journal of Wildlife Management 75(8):1753–1766; 2011; DOI: 10.1002/jwmg.232. The Wildlife Society; 11/2011.
- P - Johnson, H. E., L. S. Mills, J. D. Wehausen, T. R. Stephenson and G. Luikart. 2011. Translating Effects of Inbreeding Depression on Component Vital Rates to Overall Population Growth in Endangered Bighorn Sheep. (PDF) Conservation Biology, Volume 25, No. 6, 1240–1249. 2011
- P - Monteith, K.L, V.C. Bleich, T. R. Stephenson, Becky M. Pierce, Mary M. Conner, Robert W. Klaver, and R. Terry Bowyer. 2011. Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics Ecosphere, Volume 2(4) v Article 47. 4/2011
- P - Schroeder, C. A., R. T. Bowyer, V. C. Bleich, and T. R. Stephenson. 2010. Sexual segregation in Sierra Nevada bighorn sheep, Ovis Canadensis sierrae: ramifications for conservation. Arctic, Antarctic, and Alpine Research 42: p 476-489.
- P - Johnson, H. E., L. S. Mills, J. D. Wehausen, and T. R. Stephenson. 2010. Combining ground count, telemetry, and mark-resight data to infer population dynamics in an endangered species. Journal of Applied Ecology 47:1083-1093.
- P - Johnson, H. E., L. S. Mills, T. R. Stephenson, and J. D. Wehausen. 2010. Population-specific vital rate contributions influence management of an endangered ungulate. Ecological Applications 20:1753-1765.
- P - Clifford, D. L., B. A. Schumaker, T. R. Stephenson, V. C. Bleich, M. L. Cahn, B. J. Gonzales, W. M. Boyce, and J. A. K. Mazet. Assessing risk of disease transmission at the wildlife-livestock interface: a study of Sierra Nevada bighorn sheep. Biological Conservation. 2009, 42: 2559-2568.
- P - Cook, R. C., J. G. Cook, T.R.Stephenson, W.L. Myers, S.M. McCorquodale, D.J. Vales, L.L Irwin, P.B. Hall, R.D. Spencer, S.L. Murphie, K.A. Shoenecker and P.J. Miller Revisions of rump fat and body scoring indices for deer, elk, and moose. Journal of Wildlife Management 74(4):880–896; 2010; DOI: 10.2193/2009-031.
- P - Bishop, C. J., G. C. White, D. J. Freddy, B. E. Watkins, and T. R. Stephenson. 2009. Effect of enhanced nutrition on mule deer population rate of change. Wildlife Monographs 172:1-28.
- P - Haskell, S. P., W. B. Ballard, D. A. Butler, M. C. Wallace, T. R. Stephenson, O. J. Alcumbrac, and M. H. Humphrey. 2008. Factors affecting birth dates of sympatric deer in west-central Texas. Journal of Mammalogy 89:448-458.
- P - Villepique, J.T., V.C. Bleich, B.M. Pierce, R.A. Botta, T.R. Stephenson, and R.T. Bowyer. 2008. Evaluating GPS collar error: a critical evaluation of Televilt POSREC-Science™ collars and a method for screening location data. California Fish and Game 94:155-168.
- P - Cook, R. C., T. R. Stephenson, W. L. Myers, J. G. Cook, and L. A. Shipley. 2007. Validating predictive models of nutritional condition for mule deer. Journal of Wildlife Management 71:1934-1943.
- P - Bishop, C. J., D. J. Freddy, G. C. White, B. E. Watkins, T. R. Stephenson, and L. L. Wolfe. 2007. Using vaginal implant transmitters to aid in capture of mule deer neonates. Journal of Wildlife Management 71:945-954.
- P - Bleich, V. C., T. R. Stephenson, B. M. Pierce, and M. J. Warner. 2007. Body condition of radio-collared mule deer while injured and following recovery. Southwestern Naturalist 52:164-167.
- P - McNay, M. E., T. R. Stephenson, and B. W. Dale. 2006. Diagnosing pregnancy, in utero litter size, and fetal growth with ultrasound in wild, free-ranging wolves. Journal of Mammalogy 87:85-92.
- P - Stephenson, T. R., V. Van Ballenberghe, J. M. Peek, and J. G. MacCracken. 2006. Spatio-temporal constraints on moose habitat in coastal Alaska: vegetation succession and climate. Rangeland Ecology and Management. 59:359-372.
- P - Parker, K. L., P. S. Barboza, and T. R. Stephenson. 2005. Protein conservation in female caribou (Rangifer tarandus): effects of decreasing diet quality during winter. Journal of Mammalogy 86:610-622.
- PE -Bleich, V. C., J. T. Villepique, T. R. Stephenson, B. M. Pierce, and G. M. Kutliyev. 2005. Efficacy of aerial telemetry as an aid to capture specific individuals: a comparison of two techniques. Wildlife Society Bulletin 33:332-336.
- B - Bleich, V. C., J. G. Kie, E. R. Loft, T. R. Stephenson, M. W. Oehler, and A. L. Medina. 2005. Managing rangelands for wildlife. In C. Braun, ed. Research and management techniques for wildlife and habitats. Sixth ed., rev. The Wildlife Society, Bethesda, MD.
- P - Spaeth, D. F., R. T. Bowyer, T. R. Stephenson, and P. S. Barboza. 2004. Sexual segregation in Moose Alces alces: an experimental test of foraging behaviour. Wildlife Biology 10:59-67.
- P - Krausman, P. R., V. C. Bleich, J. W. Cain, T. R. Stephenson, D. W. DeYoung, P. W. McGrath, P. K. Swift, B. M. Pierce, and B. D. Jansen. 2004. Neck lesions in ungulates from collars incorporating satellite technology. Wildlife Society Bulletin 32:987-991.
- P - Bleich, V. C., T. R. Stephenson, N. J. Holste, I. C. Snyder, J. P. Marshal, P. W. McGrath, and B. M. Pierce. 2003. Effects of tooth extraction on body condition and reproduction of mule deer. Wildl. Soc. Bull. 31:233-236.
- P - Spaeth, D. F., R. T. Bowyer, T. R. Stephenson, P. S. Barboza, and V. Van Ballenberghe. 2002. Nutritional quality of willows for moose: effects of twig age and diameter. Alces 38:143-154.
- PE -Swift, P.K., V. C. Bleich, T. R. Stephenson, A. E. Adams, B. J. Gonzales, B. M. Pierce, and J. P. Marshal. 2002. Tooth extraction from live-captured mule deer in the absence of chemical immobilization. Wildl. Soc. Bull. 30:253-255.
- P - Stephenson, T. R., V. C. Bleich, B. M. Pierce, and G. Mulcahy. 2002. Validation of mule deer body composition using in vivo and post-mortem indices of nutritional condition. Wildl. Soc. Bull. 30:557-564.
- P - Jenkins, S. G., S. T. Partridge, T. R. Stephenson, S. D. Farley, C. T. Robbins. 2001. Nitrogen and carbon isotope fractionation between mothers, neonates, and nursing offspring. Oecologia 129:336-341.
- P - Stephenson, T. R., K. J. Hundertmark, J. A. Crouse, and M. A. Keech. 2001. Vitamin E, selenium, and reproductive losses in Alaskan moose. Alces 37:201-206.
- P - Spaeth, D. F., K. J. Hundertmark, R. T. Bowyer, P. S. Barboza, T. R. Stephenson, and R. O. Peterson. 2001. Incisor arcades of Alaskan moose: is dimorphism related to sexual segregation? Alces 37:217-226.
- P - Keech, M. A., R. T. Bowyer, J. M. Ver Hoef, R. D. Boertje, B. W. Dale, and T. R. Stephenson. 2000. Life-history consequences of maternal condition in Alaskan moose. J. Wildl. Manage. 64:450-462.
- P - Huang, F., D. C. Cockrell, T. R. Stephenson, J. H. Noyes, R. G. Sasser. 2000. A specific radioimmunoassay for moose and elk pregnancy-specific protein B in serum. J. Wildl. Manage. 64:492-499.
- P - Huang, F., D. C. Cockrell, T. R. Stephenson, J. H. Noyes, and R. G. Sasser. 1999. Isolation, purification, and characterization of pregnancy-specific protein B from elk and moose placenta. Biol. Reprod. 61:1056-1061.
- P - Stephenson, T. R., V. Van Ballenberghe, and J. M. Peek. 1998. Response of moose forages to mechanical cutting on the Copper River Delta, Alaska. Alces 34:479-494.
- P - Stephenson, T. R., K. J. Hundertmark, C. C. Schwartz, and V. Van Ballenberghe. 1998. Predicting body fat and body mass in moose with ultrasonography. Can. J. Zool. 76:717-722.
- P - Keech, M. A., T. R. Stephenson, R. T. Bowyer, V. Van Ballenberghe, and J. M. Ver Hoef. 1998. Relationships between blood-serum and depth of rump fat in Alaskan moose. Alces 34:173-179.
- P - Rodgers, A. R., S. M. Tomkiewicz, E. J. Lawson, T. R. Stephenson, K. J. Hundertmark, P. J. Wilson, B. N. White, and R. S. Rempel. 1998. New technology for moose management: a workshop. Alces 34:239-244.
- P - Shochat, E., C. T. Robbins, S. M. Parish, P. B. Young, T. R. Stephenson, and A. Tamayo. 1997. Nutritional investigations and management of captive moose. Zoo Biol. 16:479-494.
- P - Schwartz, C. C., T. R. Stephenson, and K. J. Hundertmark. 1997. Xylazine immobilization of moose with yohimbine or tolazoline as an antagonist: a comparison to carfentanil and Naltrexone. Alces 33:33-42.
- P - Stephenson, T. R., M. R. Vaughan, and D. E. Andersen. 1996. Mule deer movements in response to military activity in southeast Colorado. J. Wildl. Manage. 60:777-787.
- P - Stephenson, T. R., J. W. Testa, G. P. Adams, R. G. Sasser, C. C. Schwartz, and K. J. Hundertmark. 1995. Diagnosis of pregnancy and twinning in moose by ultrasonography and serum assay. Alces 31:167-172.
- P - Stephenson, T. R., and V. Van Ballenberghe. 1995. Wolf, Canis lupus, predation on Dusky Canada Geese, Branta canadensis occidentalis. Can. Field-Nat. 109:253-255.
- P - Stephenson, T. R., and V. Van Ballenberghe. 1995. Defense of one twin calf against wolves, Canis lupus, by a female moose, Alces alces. Can. Field-Nat. 109:251-253.
- P - MacCracken, J. G., T. R. Stephenson, and V. Van Ballenberghe. 1994. Peculiar antler cast by moose on the Copper River Delta, Alaska. Alces 30:13-19.
- P - Stephenson, T. R., K. J. Hundertmark, C. C. Schwartz, and V. Van Ballenberghe. 1993. Ultrasonic fat measurement of captive yearling bull moose. Alces 29:115-123.
- P - Stephenson, T. R. 1988. Mammalian prey selection by a captive bobcat. Southwest. Nat. 33:104-105.
- P - Stephenson, T. R., J. M. Peek, J. G. MacCracken, and V. Van Ballenberghe Spatio-Temporal Constraints on Moose Habitat and Carrying Capacity in Coastal Alaska: Vegetation Succession and Climate, Rangeland Ecology & Management, pp. 359-372.