Jake Ivan, Wildlife Research Scientist

Jake Ivan
Wildlife Research Scientist, Species of Conservation Concern

Current or Recent Research Projects

• Snowshoe Hare Response to Silvicultural Treatments
• Monitoring Canada Lynx in Colorado
• Mammal and Breeding Bird Response to Bark Beetle Outbreaks

Areas of Interest and Expertise

My research focuses on estimating wildlife population parameters and forest carnivore ecology, conservation and monitoring. 

Streaming Videos

• Catching pine
• Lynx: shadows of the forest
• Snowshoe hare
• Snowshoe hare releases
• Snowshoe hare trapping, collaring and release

Select Publications

• Ivan, J. S. 2024. Canada Lynx (lynx Canadensis). Pages 129-152 in J. E. Cartron and J. K. Frey, Eds. Wild Carnivores of New Mexico. University of New Mexico Press.

• Hooten, M. B., M. R. Schwob, D. S. Johnson and J. S. Ivan. 2024. Geostatistical capture-recapture models​​. Spatial Statistics 59:100817. doi.org/10.1016/j.spasta.2024.100817​
• Squires, J. R., Olson, L. E., Ivan, J. S., McDonald, P. M., and Holbrook, J. D. 2024. Anthropogenically protected but naturally disturbed: a specialist carnivore at its southern range periphery. Biodiversity and Conservation. https://doi.org/10.1007/s10531-024-02978-8
• Hooten, M. B., M. R. Schwob, D. S. Johnson, and J. S. Ivan. 2023. Multistage hierarchical capture-recapture models. Environmetrics 34:e2799. doi.org/10.1002/env.2799
• Ivan, J. S., E. S. Newkirk, and B. D. Gerber. 2023. Differential impacts of spruce beetle outbreaks on snowshoe hares and red squirrels in the southern Rocky Mountains​. Forest Ecology and Management 544:121147. doi.org/10.1016/j.foreco.2023.121147
• Squire​s, J. R., J. S. Ivan, K. E. Paolini, L. E. Olson, G. M. Jones, and J. D. Holbrook​​. 2022. Keystone structures maintain forest function for Canada lynx after large-scale spruce beetle outbreak​​. Environmental Research: Ecology 2:011001. https://doi.org/10.1088/2752-664X/ac8eb7
• Van Ee, J. J., J. S. Ivan, and M. B. Hooten. 2022. Community confounding in joint species distribution models. Scientific Reports 12:1–14. https://doi.org/10.1038/s41598-022-15694-6​
• Kraberger, S., L. E. K. Serieys, C. Richet, N. M. Fountain-Jones, G. Baele, J. M. Bishop, M. Nehring, J. S. Ivan, E. S. Newkirk, J. R. Squires, M. C. Lund, S. P. D. Riley, C. C. Wilmers, P. D. van Helden, K. Van Doorslaer, M. Culver, S. VandeWoude, D. P. Martin, and A. Varsani. 2021. Complex evolutionary history of felid anelloviruses. Virology 562:176–189. https://doi.org/10.1016/j.virol.2021.07.013
• Olson, L. E., N. Bjornlie, G. Hanvey, J. D. Holbrook, J. S. Ivan, S. Jackson, B. Kertson, T. King, M. Lucid, D. Murray, R. Naney, J. Rohrer, A. Scully, D. Thornton, Z. Walker, and J. R. Squires. 2021. Improved prediction of Canada lynx distribution through regional model transferability and data efficiency. Ecology and Evolution 11:1667–1690. https://doi.org/10.1002/ece3.7157
• Squires, J. R., J. D. Holbrook, L. E. Olson, J. S. Ivan, R. W. Ghormley, and R. L. Lawrence. 2020. A specialized forest carnivore navigates landscape-level disturbance: Canada lynx in spruce-beetle impacted forests. Forest Ecology and Management 475:118400. https://doi.org/10.1016/j.foreco.2020.118400
• Tabak, M. A., M. S. Norouzzadeh, D. W. Wolfson, E. J. Newton, R. K. Boughton, J. S. Ivan, E. A. Odell, E. S. Newkirk, R. Y. Conrey, J. Stenglein, F. Iannarilli, J. Erb, R. K. Brook, A. J. Davis, J. Lewis, D. P. Walsh, J. C. Beasley, K. C. VerCauteren, J. Clune, and R. S. Miller. 2020. Improving the accessibility and transferability of machine learning algorithms for identification of animals in camera trap images: MLWIC2. Ecology and Evolution 10:10374-10383. https://doi.org/10.1002/ece3.6692
• Latif, Q. S., J. S. Ivan, A. E. Seglund, D. L. Pavlacky, and R. L. Truex. 2020. Avian relationships with bark beetle outbreaks and underlying mechanisms in lodgepole pine and spruce-fir forests of Colorado. Forest Ecology and Management 464:118043. https://doi.org/10.1016/j.foreco.2020.118043
• Lukacs, P. M., D. Evans Mack, R. Inman, J. A. Gude, J. S. Ivan, R. P. Lanka, J. C. Lewis, R. A. Long, R. Sallabanks, Z. Walker, S. Courville, S. Jackson, R. Kahn, M. K. Schwartz, S. C. Torbit, J. S. Waller, and K. Carroll. 2020. Wolverine occupancy, spatial distribution, and monitoring design. The Journal of Wildlife Management 84:841–851. https://doi.org/10.1002/jwmg.21856
• Zimova, M., A. P. Sirén, J. J. Nowak, A. M. Bryan, J. S. Ivan, T. L. Morelli, S. L. Suhrer, J. Whittington, and L. S. Mills. 2019. Local climate determines vulnerability to camouflage mismatch in snowshoe hares. Global Ecology and Biogeography 29:503–515.  https://doi.org/10.1111/geb.13049
• Gigliotti, L. C., N. D. Berg, R. Boonstra, S. M. Cleveland, D. R. Diefenbach, E. M. Gese, J. S. Ivan, K. Kielland, C. J. Krebs, A. V. Kumar, L. S. Mills, J. N. Pauli, H. B. Underwood, E. C. Wilson, and M. J. Sheriff. 2019. Latitudinal variation in snowshoe hare (Lepus americanus) body mass: a test of Bergmann’s rule. Canadian Journal of Zoology 98:88–95. https://doi.org/10.1139/cjz-2019-0184
• Squires, J. R., L. E. Olson, E. K. Roberts, J. S. Ivan, and M. Hebblewhite. 2019. Winter recreation and Canada lynx: reducing conflict through niche partitioning. Ecosphere 10:e02876. https://doi.org/10.1002/ecs2.2876
• Ivan, J. S. 2019. Density estimation. Pages 20.1–20.19 in E. G. Cooch and G. C. White, editors. Program MARK - 'a gentle introduction'.
• Ayers, C. R., K. C. Hanson-Dorr, K. Stromborg, T. W. Arnold, J. S. Ivan, and B. S. Dorr. 2019. Survival, fidelity, and dispersal of double-crested cormorants on two Lake Michigan Islands. The Auk 136:1-10. https://doi.org/10.1093/auk/ukz040​
• Magee, P. A., J. D. Coop, and J. S. Ivan. 2019. Thinning alters avian occupancy in piñon–juniper woodlands. The Condor 121:1-17. https://doi.org/10.1093/condor/duy008
• Tabak, M. A., M. S. Norouzzadeh, D. W. Wolfson, S. J. Sweeney, K. C. Vercauteren, N. P. Snow, J. M. Halseth, P. A. Di Salvo, J. S. Lewis, M. D. White, B. Teton, J. C. Beasley, P. E. Schlichting, R. K. Boughton, B. Wight, E. S. Newkirk, J. S. Ivan, E. A. Odell, R. K. Brook, P. M. Lukacs, A. K. Moeller, E. G. Mandeville, J. Clune, and R. S. Miller. 2018. Machine learning to classify animal species in camera trap images: applications in ecology. Methods in Ecology and Evolution 10:585–590.  https://doi.org/10.1111/2041-210X.13120 
• Buderman, F. E., M. B. Hooten, M. W. Alldredge, E. M. Hanks, and J. S. Ivan. 2018. Time-varying predatory behavior is primary predictor of fine-scale movement of wildland-urban cougars. Movement Ecology 6:22. https://doi.org/10.1186/s40462-018-0140-6 
• Ivan, J. S., A. E. Seglund, R. L. Truex, and E. S. Newkirk. 2018. Mammalian responses to changed forest conditions resulting from bark beetle outbreaks in the southern Rocky Mountains. Ecosphere 9:e02369. https://doi.org/10.1002/ecs2.2369
• Olson, L. E., J. R. Squires, E. K. Roberts, J. S. Ivan, and M. Hebblewhite. 2018. Sharing the same slope: behavioral responses of a threatened mesocarnivore to motorized and nonmotorized winter recreation. Ecology and Evolution 8:8555-8572. https://doi.org/10.1002/ece3.4382 
• Olson, L. E., J. R. Squires, E. K. Roberts, A. D. Miller, J. S. Ivan, and M. Hebblewhite. 2017. Modeling large-scale winter recreation terrain selection with implications for recreation management and wildlife. Applied Geography 86:66-91.  https://doi.org/10.1016/j.apgeog.2017.06.023
• Buderman, F. E., M. B. Hooten, J. S. Ivan, and T. M. Shenk. 2018. Large-scale movement behavior in a reintroduced predator population. Ecography 41:126-139.  https://onlinelibrary.wiley.com/doi/ftr/10.1111/ecog.03030
• Baigas, P. E., J. R. Squires, L. E. Olsen, J. S. Ivan, and E. K. Roberts. 2017. Using environmental features to model highway crossing behavior of Canada lynx in the Southern Rocky Mountains. Landscape and Urban Planning 157:200-213.  https://doi.org/10.1016/j.landurbplan.2016.06.007
• Hooten, M. B., F. E. Buderman, B. M. Brost, E. M. Hanks, and J. S. Ivan. 2016. Hierarchical animal movement models for population-level inference. Environmetrics 27:322-333.  https://doi.org/10.1002/env.2402
• Ivan, J. S., and T. M. Shenk. 2016. Winter diet and hunting success of Canada lynx in Colorado. The Journal of Wildlife Management 80:1049-1058. https://doi.org/10.1002/jwmg.21101
• Ivan, J. S., and E. S. Newkirk. 2016. CPW Photo Warehouse: a custom database to facilitate archiving, identifying, summarizing, and managing photo data collected from camera traps. Methods in Ecology and Evolution 7:499-504. https://doi.org/10.1111/2041-210X.12503
• Buderman, F. E., M. B. Hooten, J. S. Ivan, and T. M. Shenk. 2016. A functional model for characterizing long-distance movement behavior. Methods in Ecology and Evolution 7:264-273. https://doi.org/10.1111/2041-210X.12465
• Ellis, M. M., J. S. Ivan, J. M. Tucker, and M. K. Schwartz. 2015. rSPACE: Spatially based power analysis for conservation and ecology. Methods in Ecology and Evolution 6:621-625. https://doi.org/10.1111/2041-210X.12369
• Ivan, J. S., G. C. White, and T. M. Shenk. 2014. Density and demography of snowshoe hares in central Colorado. The Journal of Wildlife Management 78:580–594. https://doi.org/10.1002/jwmg.695
• Gerber, B. D., J. S. Ivan, and K. P. Burnham. 2014. Estimating the abundance of rare and elusive carnivores from photographic-sampling data when the population size is very small. Population Ecology 56:463-470. https://doi.org/10.1007/s10144-014-0431-8
• Trainor, A. M., O. J. Schmitz, J. S. Ivan, and T. M. Shenk. 2014. Enhancing species distribution modeling by characterizing predator–prey interactions. Ecological Applications 24:204–216. https://doi.org/10.1890/13-0336.1
• Ellis, M. M., J. S. Ivan, and M. K. Schwartz. 2014. Spatially explicit power analyses for occupancy-based monitoring of wolverine in the U.S. Rocky Mountains. Conservation Biology 28:52–62. https://doi.org/10.1111/cobi.12139
• Ivan J. S., G. C. White, and T. M. Shenk. 2013. Using simulation to compare methods for estimating density from capture-recapture data. Ecology 94:817–826. https://doi.org/10.1890/12-0102.1
• Ivan, J. S., G. C. White, and T. M. Shenk. 2013. Using auxiliary telemetry information to estimate animal density from capture-recapture data. Ecology 94:809–816. https://doi.org/10.1890/12-0101.1
• Stromborg, K. L., J. S. Ivan, J. K. Netto, and C. R. Courtney. 2012. Survivorship and mortality patterns of double-crested cormorants at Spider Island, Wisconsin, 1988–2006. Waterbirds 35:31–39. https://doi.org/10.1675/063.035.sp105

Education

• Ph.D., Fish, Wildlife and Conservation Biology — Colorado State University, 2011
• M.S., Wildlife Biology — University of Montana, 2000
• B.S., Wildlife Science — Purdue University, 1997

Current or Recent Positions

• Wildlife Researcher — Colorado Parks and Wildlife, 2010–Present
• Refuge Biologist — U.S. Fish and Wildlife Service, 2003-2005
• Piping Plover Recovery Biologist — The Nature Conservancy, 2000-2003