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Staff Bios
Staff Bios

​​​Staff members:

Anthony Dean Apa Dr. Apa

Anthony Dean Apa Dr. Apa began his career as a researcher with the Colorado Parks and Wildlife in November 1999. He was raised in Nebraska and received his B.S. degree from the University of Montana, an M.S. degree from South Dakota State University, and his Ph.D. from the University of Idaho. His Ph.D. research focused on the habitat use and movements of sympatric Greater Sage-grouse and Columbian Sharp-tailed Grouse. He has been involved in research and/or management of sage-grouse in 2 states (Colorado and Idaho) for over 20 years. He was a technical expert for the development of the Gunnison Sage-grouse Range wide Conservation Plan and the Greater Sage-grouse Statewide Plan. Dr. Apa is currently continuing his research on the ecology and management of grouse species in Colorado.

Selected Publications:
Walsh, D.P., J.R. Stiver, G.C. White, T.E. Remington, and A.D. Apa. 2010. Population estimation techniques for lekking species. Journal of Wildlife Management 74:1607-1613.

Stiver, J. R., A. D. Apa, T. E. Remington, and R. M. Gibson.  2008.  Polygyny and female breeding failure reduce effective population size in the lekking Gunnison sage-grouse.  Biological Conservation 141:472-481.

Stiver, S.J., A.D. Apa, J.R. Bohne, S.D. Bunnell, P.A. Deibert, S.C. Gardner, M.A. Hilliard, C.W. McCarthy, and M.A. Schroeder. 2006. Greater sage-grouse comprehensive conservation strategy. Western Association of Fish and Wildlife Agencies.  Unpublished Report. Cheyenne, Wyoming.

Hausleitner, D., K.P. Reese, and A.D. Apa. 2005. Timing of vegetation sampling at greater sage-grouse nests. Rangeland Ecology & Management 58:553-556.

Oyler-McCance, S.J., J. St. John, S.E. Taylor, A.D. Apa, and T.W. Quinn. 2005. Population genetics of Gunnison sage-grouse: Implications for management. Journal of Wildlife Management 69:630-637.

Schroeder, M.A., C.L. Aldridge, A.D. Apa, J.R. Bohne, C.E. Braun, S.D. Bunnell, J.W. Connelly, P.A. Deibert, S.C. Gardner, M.A. Hilliard, G.D. Kobriger, S.M. McAdam, C.W. McCarthy, D.L. Mitchell, E.V. Rickerson, and S.J. Stiver. 2004. Distribution of the sage-grouse in North America. Condor 106:363-376.

Connelly, J.W., A.D. Apa, R.B. Smith, and K.P. Reese. 2000. Effects of predation and hunting on adult sage grouseCentrocercus urophasianus in Idaho. Wildlife Biology 6:227-232.

Apa, A.D. K.P. Reese, and J.W. Connelly, Jr. 1997. An evaluation of nest placement theory using artificial and Columbian sharp-tailed grouse Tympanchus phasianellus columbianus nests. Wildlife Biology 3:278.

Reesa Y. Conrey

Dr. Conrey began her career as a researcher with the Colorado Parks and Wildlife in June 2012. She received a B.A. degree from Dartmouth College, an M.S. at the University of Montana, and a Ph.D. at Colorado State University. Her Ph.D. research focused on the effects of plague on the ecology of burrowing owls associated with black-tailed prairie dog colonies in Colorado.  She has also worked at the USGS Science Center in Fort Collins, examining responses of shortgrass prairie birds to climate change, and with the Rocky Mountain Bird Observatory, conducting research and administering habitat conservation projects.  Dr. Conrey is currently developing new research projects to address information needs for the suite of shortgrass prairie avifauna species that occupy the eastern plains of Colorado.

Selected Publications:
Dreitz, V.J., R. Y. Conrey, and S. K. Skagen.  In press.  Drought and cooler temperatures are associated with higher nest survival in mountain plovers.  Avian Conservation and Ecology.James H. Gammonley Dr. Gammonley began his career as a researcher with the Colorado Parks and Wildlife in March 1995, and has been the Avian Research Program Manager since September 2005. He received a B.S. degree from the University of California at Davis, and an M.S. and Ph.D. from the University of Missouri at Columbia. His past research experience centered on understanding the ecology and management of waterfowl and other wetland birds.  He serves as Colorado's representative on the Central Flyway Council's Waterfowl, Webless Migratory Game Bird, and Central Management Unit Technical Committees.

Selected Publications:
Witter, D., D. J. Case, J.H. Gammonley, and D. Childress. 2006. Social factors in waterfowl management: conservation goal, public perception, and hunter satisfaction.  Transactions of the North American Wildlife and Natural Resources Conference.

Connelly, J., J.H. Gammonley, and J.M. Peek. 2005. Harvest management.  Pages 658-690 in C. E. Braun, editor. Techniques for wildlife investigations and management.  Sixth edition. The Wildlife Society, Bethesda, Maryland, USA.

Gammonley, J.H. 2004. Wildlife use of natural palustrine wetlands in the Intermountain West. Pages 130-153 in M.C. McKinstry, W.A. Hubert, and S.H. Anderson, editors.  Wetland and riparian areas the intermountain West. University of Wyoming, Laramie.

Gammonley, J.H., and M.K. Laubhan. 2002. Patterns of food abundance for breeding waterbirds in the San Luis Valley of Colorado. Wetlands 22:409-508.

Laubhan, M.K., and J.H. Gammonley. 2001. Agricultural producers’ perceptions of sandhill cranes in the San Luis Valley of Colorado. Wildlife Society Bulletin 29:639-645.

Humburg, D.A., T.W. Aldrich, S. Baker, G. Costanzo, J.H. Gammonley, M.A. Johnson, B. Swift, and D. Yparraguirre. 2000. Adaptive harvest management: has anything really changed?  Transactions of the North American Wildlife and Natural Resources Conference.

Laubhan, M.K., and J.H. Gammonley. 2000. Density and foraging habitat selection of waterbirds breeding in the San Luis Valley of Colorado. Journal of Wildlife Management 64:808-819.

Danielle M. Johnston

Danielle M. Johnston(formerly Bilyeu)  Dr. Johnston began her career as a researcher with the Colorado Parks and Wildlife in June 2007. She received a B.A. degree from Rice University, and a Ph.D. from Colorado State University. Although she has done some direct work with birds, Dr. Johnston’s expertise is in plant ecology. The focus of her research is to evaluate and improve techniques used to manage habitats for birds and other wildlife in Colorado. Her current focus is on developing techniques to restore and manage native plants in sagebrush habitats of western Colorado. See Dr. Johnston's research on the Wildlife Habitat Research page. 

Selected Publications:
Johnston, D.B.
 2011. Movement of weed seeds in reclamation areas. Restoration Ecology 19:446-449.

Bilyeu D.M., D.J. Cooper, and N.T. Hobbs NT. 2008. Water tables constrain height recovery of willow on Yellowstone's Northern Range. Ecological Applications 18:80-92.

Bilyeu D.M., D.J. Cooper, and N.T. Hobbs NT. 2007. Assessing impacts of large herbivores on shrubs: tests of scaling factors for utilization rates from shoot-level measurements.  Journal of Applied Ecology 44:168-175

Johnston D.B., D.J. Cooper, and N.T. Hobbs NT. 2007. Elk browsing relieves water stress and promotes productivity of willow with low water table in Yellowstone National Park.  Oecologia 154:467-478.

Elizabeth "Lee" Olton

Lee Olton is the Program Assistant for the Avian Research Program. She began her career with the Colorado Parks and Wildlife in January 1992. Prior to joining the CPW, Lee was the Operations Manager of the Tissue Culture for Crops Project at Colorado State University, a project funded by the United States Agency for International Development, under the auspice of the Biology Department. Lee has worked for the State of Colorado since March 1985.

Michael L. Phillips

Dr. Phillips began his career as a researcher with the Colorado Parks and Wildlife in July 2003. He received a B.A. degree from the University of Illinois, an M.S. degree in Animal Behavior from the University of Missouri at St. Louis, and a Ph.D. in Animal Ecology from Iowa State University for his work on the movement patterns of predators and their interaction with prey species (waterfowl) in prairie landscapes. He was a postdoctoral fellow at the Northern Prairie Wildlife Research Center (USGS) in North Dakota and at the University of Florida where he continued work on examining wildlife-habitat relationships. His primary research interest is in combining field ecology with statistical and spatial simulation modeling to examine the effect of landscape structure on the behavioral ecology and population dynamics of vertebrate species. Landscape structure is determined by the various types and spatial arrangement of habitats in a landscape and can influence individual movement patterns, reproductive success and recruitment into local populations. Dr. Phillips' current research with the Colorado Parks and Wildlife is focused on the ecology and conservation of Gunnison Sage-grouse.

Selected Publications:
Horn, D.J., M.L. Phillips, R.R. Koford, W.R. Clark, M.A. Sovada, and R.J. Greenwood. 2005. Landscape composition, patch size, and distance to edges: interactions affecting duck reproductive success. Ecological Applications 15:1367-1376.

Phillips, M.L., W.R. Clark, S.M. Nusser, M.A. Sovada, and R.J. Greenwood. 2004. Analysis of predator movement in prairie landscapes with contrasting grassland compositions.  Journal of Mammalogy 85:187-195.

Phillips, M.L., W.R. Clark, M.A. Sovada, D.J. Horn, R.R. Koford, and R.J. Greenwood. 2003.  Predator selection of prairie landscape features and its relation to duck nest success.  Journal of Wildlife Management 67:104-114.

Sovada, M.A., C.C. Slivinski, R.O. Woodward, and M.L. Phillips. 2003. Home range, habitat use, litter size, and pup dispersal of swift foxes in two distinct landscapes of western Kansas. Pages149-160 in M.A. Sovada and L. Carbyn, editors. The Swift Fox: Ecology and Conservation of Swift Foxes in a Changing World. Canadian Plains Research Center, University of Regina.

Mindy B. Rice

Dr. Rice began her career as a researcher with the Colorado Parks and Wildlife in June 2008. She earned a B.S. in Zoology from Colorado State University, an M.S. in Conservation Ecology from Manchester Metropolitan University, United Kingdom, and a Ph.D. in Wildlife Management at Texas Tech University in 2006. Dr. Rice’s primary interest and expertise is in the spatial ecology of wildlife.  She is currently involved in spatial modeling and analysis of a variety of wildlife populations in Colorado, including greater sage-grouse, mule deer, and black bears.

Selected Publications:
Rice, M. B.
, D. A. Haukos, J. D. Dubovsky, and M. Runge.  2010. Survival rates of northern pintails (Anas acuta) using continental band-recovery data.   Journal of Wildlife Management 74: 778-787.

Saalfeld, S. T., W. C. Conway, D. A. Haukos, M. Rice, S. L. Jones, and S. D. Fellows. 2010. Multiscale habitat selection by long-billed curlews (Numenius americanus) breeding in the United States.  Waterbirds 33: 148-161.

Rice, M. B., W. B. Ballard, E. B. Fish, N. E. McIntyre, and D. Holdermann.  2009. Habitat distribution modeling of a recognizing black bear, Ursus americanus, population in the Trans-Pecos region of Texas.  Canadian Field Naturalist 123:246-254.

Rice, M. B., W. B. Ballard, E.B. Fish, N.E. McIntyre, and D. Holdermann. 2008. The importance of accurate land use/land cover maps for assessing habitat utilization by black bear in the Trans-Pecos region of Texas. Wildlife Biology in Practice 4:48-56.

Rice, M.B., W.B. Ballard, E.B. Fish, D.B. Webster, and D. Holdermann. 2007. Landowner attitudes toward black bears in the Trans-Pecos region of Texas. Human Dimensions of Wildlife 12:405-415.

Rice, M.B., and M. Jones. 2006. Characteristics of black rhino (Diceros bicornis) bedding sites. African Journal of Ecology 44:452-457.

Brett L. Walker

Dr. Walker began his career as a researcher with the Colorado Parks and Wildlife in June 2007. He received a B.S. degree from the University of California–Berkeley, an M.S. degree from the University of Montana–Missoula, and a Ph.D. from the University of Montana–Missoula. His expertise is in avian behavioral and population ecology, and he has extensive field experience working with a variety of game and non-game bird species. Dr. Walker’s current focus is on responses of greater sage-grouse to energy development and other landscape-level changes in sagebrush steppe habitats in western Colorado.

Selected Publications:
Taylor, R., B. L. Walker, L. S. Mills, and D. E. Naugle. 2011. Managing multiple vital rates to maximize greater sage-grouse population growth. Journal of Wildlife Management 76:336-347.

Naugle, D. E., K. E. Doherty, B. L. Walker, H. E. Copeland, and J. D. Tack. 2011. Sage-grouse and cumulative impacts of energy development. In P. Krausman, ed., Cumulative Effects in Wildlife Management: Mitigating Impacts. CRC Press. 288 p.

Naugle, D. E., K. E. Doherty, B. L. Walker, H. E. Copeland, M. J. Holloran, and J. D. Tack. 2011. Sage-grouse and cumulative impacts of energy development. In D. E. Naugle, ed., Energy Development and Wildlife Conservation in Western North America. Island Press. 357 p.

Walker, B. L. and D. E. Naugle. 2011. West Nile virus ecology in sagebrush habitat and impacts on Greater Sage-grouse populations. Pp. 127-142 in S. T. Knick and J. W. Connelly (eds.). Greater sage-grouse: ecology and conservation of a landscape species and its habitats. Studies in Avian Biology, Vol. 38, University of California Press, Berkeley, CA, USA.

Naugle , D. E., K. E. Doherty, B. L. Walker, M. J. Holloran, and H. Copeland. 2011. Energy development and greater sage-grouse. Pp. 489-503 in S. T. Knick and J. W. Connelly (eds.). Greater sage-grouse: ecology and conservation of a landscape species and its habitats. Studies in Avian Biology, Vol. 38, University of California Press, Berkeley, CA, USA.

Bush, K. L., C. K. Dyte, B. J. Moynahan, C. L. Aldridge, H. S. Sauls, A. M. Batazzo, B. L. Walker, K. E. Doherty, J. D. Tack, J. Carlson, D. Eslinger, J. Nicholson, M. S. Boyce, D. E. Naugle, C. A. Paszkowski, and D. W. Coltman. 2011. Population structure and genetic diversity of greater sage-grouse (Centrocercus urophasianus) in fragmented landscapes at the northern edge of their range. Conservation Genetics 12:527-542.

Schrag, A. M., S. K. Konrad, S. N. Miller, B. L. Walker, and S. Forrest. 2010. Climate-change impacts on sagebrush habitat and West Nile virus transmission risk and conservation implications for greater sage-grouse. Geojournal. Published on-line. DOI 10.1007/s10708-010-9369-3.

Doherty, K. E., D. E. Naugle, and B. L. Walker. 2010. Greater sage-grouse nesting habitat: the importance of managing at multiple scales. Journal of Wildlife Management 74:1544-1553.

Doherty, K. E., D. E. Naugle, and B. L. Walker. 2008. Sage-grouse winter habitat selection and energy development. Journal of Wildlife Management 72:187-195.

Walker, B. L., D. E. Naugle, and K. E. Doherty. 2007. Greater sage-grouse population response to habitat loss and coal-bed natural gas development. Journal of Wildlife Management 71: 2644-2654.

Walker, B. L., D. E. Naugle, K. E. Doherty, and T. E. Cornish. 2007. West Nile virus and greater sage-grouse: estimating infection rate in a wild bird population.  Avian Diseases 51: 691-696.

Mahony, N. A., W. M. Vander Haegen, B. L. Walker, and P. G. Krannitz. 2002. Male incubation and multiple brooding in Brewer’s sparrows. Wilson Bulletin 113:441-444.