David Gustine

A close-up of a man with a rocky mountain slope and small plane in the background
Manager/Supervisory Biologist - Polar Bears

1011 East Tudor Road
Anchorage, AK 99503
United States

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About David Gustine

David has served as the FWS Polar Bear Program lead since 2020. Prior to joining the Marine Mammals Management office, he worked as a Supervisory Wildlife Biologist for the National Park Service (Grand Teton National Park) in Wyoming and as a Research Wildlife Biologist for the U.S. Geological Survey Alaska Science Center in Anchorage. David has a Ph.D. in Biological Sciences–Wildlife Biology from the University of Alaska Fairbanks and an M.S. in Natural Resource and Environmental Science–Biology from the University of Northern British Columbia.

Professional Activities

  • Member of Chronic Wasting Disease Working Group, State of Wyoming (2019–20)
  • Member of Interagency Grizzly Bear Study Team (2015–20)
  • Member of the International Association for Bear and Research Management (2013–current)
  • Member of The Wildlife Society (2003–current)



Smith, M. M., C. Van Hemert, T. C. Atwood, D. R. Sinnett, J. W. Hupp, B. W. Meixell, D. D. Gustine, L. G. Adams, and A. M. Ramey. 2022. A serological survey of Francisella tularensis exposure in wildlife on the Arctic Coastal Plain of Alaska. Journal of Wildlife Diseases 58: DOI: 10.7589/JWD-D-21-00162.

Trujillo, S. M., E. A. McKenney, G. V. Hilderbrand, L. S. Mangipane, M. C. Rogers, K. Joly, D. D. Gustine, J. A. Erlenbach, B. A. Mangipane, and D. J. R. Lafferty. 2022. Correlating gut microbial membership to brown bear health metrics. Scientific Reports 12: DOI: 10.1038/s41598-022-19527-4.

Johnson, H., E. Lenart, D. Gustine, L. Adams, and P. Barboza. 2022. Survival and reproduction in Arctic caribou are associated with summer forage and insect harassment. Frontiers in Ecology and Evolution 10:899585. DOI: 10.3389/fevo.2022.899585

Joly, K., M. D. Cameron, M. S. Sorum, D. D. Gustine, W. Deacy, and G. V. Hilderbrand. 2022. Factors influencing Arctic brown bear annual home range sizes and limitations of home range analyses. Ursus 33: e11. DOI: 10.2192/URSUS-D-21-00015.2.

Trujillo, S. M., E. A. McKenney, G. V. Hilderbrand, L. S. Mangipane, M. C. Rogers, K. Joly, D. D. Gustine, J. A. Erlenbach, B. A. Mangipane, and D. J. R. Lafferty. 2022. Intrinsic and extrinsic factors influence on an omnivore’s gut microbiome. PLoS One 17: e0266698. DOI: 10.1371/journal.pone.0266698.

Johnson, H.E., T. S. Golden, L. G. Adams, E. A. Lenart, D. D. Gustine, and P. S. Barboza. 2021. Dynamic selection for forage quality and quantity in response to phenology and insects in an Arctic ungulate. Ecology and Evolution: 11664–11688.

Cameron, M., G. Hilderbrand, K. Joly, J. Schmidt, D. Gustine, L. Mangipane, B. Mangipane, and M. Sorum. 2021. Body size plasticity in North American black and brown bears. Ecosphere: e03235.

Fullman, T. J., R. R. Wilson, K. Joly, D. D. Gustine, P. Leonard, and W. M. Loya. 2021. Mapping potential effects of proposed roads on migratory connectivity for a highly mobile herbivore using circuit theory. Ecological Applications 31: 32207.

Rogers M. C., G. W. Hilderbrand, D. D. Gustine, K. Joly, W. B. Leacock, B. A. Mangipane, and J. M. Welker. Splitting hairs: dietary niche breadth modeling using stable isotope analysis of a sequentially grown tissue. Isotopes in Environmental and Health Studies: https://doi.org/10.1080/10256016.2020.1787404.

Mangipane, L. S., D. J. R. Lafferty, K. Joly, M. S. Sorum, M. D. Cameron, J. L. Belant, G. V. Hilderbrand, and D. D. Gustine. 2020. Dietary plasticity and the importance of salmon to brown bear body size and condition in a low arctic ecosystem. Polar Biology: https://doi.org/10.1007/s00300-020-02690-7.

Barboza, P. S., R. D. Shively, D. D. Gustine, and J. A. Addison. 2020. Winter is coming: conserving body protein in female reindeer, caribou, and muskoxen. Frontiers in Ecology and Evolution: https://doi.org/10.3389/fevo.2020.00150.

Sorum, M. S., K. Joly, M. D. Cameron, D. D. Gustine, and G. V. Hilderbrand. 2020. Salmon sleuths: GPS-collared bears lead researchers to unknown salmon streams in Interior Alaska. Alaska Park Science 19:4–9.

Johnson, H., T. Golden, L. Adams, D. Gustine, and E. Lenart. 2020. Caribou use of habitat near energy development in Arctic Alaska. Journal of Wildlife Management 84: 401–412.

van Manen, F. T., M. R. Ebinger, D. D. Gustine, M. A. Haroldson, and K. R. Wilmot. 2019. Primarily resident grizzly bears respond to late-season elk harvest. Ursus 30e1: 1–15.

Middleton, A. D., H. Sawyer, J. A. Merkle, M. J. Kauffman, E. K. Cole, S. R. Dewey, J. A. Gude, D. D. Gustine, D. E. McWhirter, and P. J. White. 2019. Conserving transboundary wildlife migrations: recent insights from the Greater Yellowstone Ecosystem. Frontiers in Ecology and Environment: doi:10.1002/fee.2145.

Sorum, M. S., K. Joly, A. G. Wells, M. D. Cameron, G. V. Hilderbrand, and D. D. Gustine. 2019. Den site characteristics and selection by brown bears (Ursus arctos) in the central Brooks Range of Alaska. Ecosphere 10: e02822. 10.1002/ecs2.2822.

Ramey, A. M., C. A. Cleveland, G. V. Hilderbrand, K. Joly, D. D. Gustine, B. Mangipane, W. B. Leacock, A. P. Crupi, D. E. Hill, J. P. Dubey, and M. J. Yabsley. 2019. Exposure of Alaska brown bears (Ursus arctos) to bacterial, viral, and parasitic agents varies spatiotemporally and is influenced by demography. Journal of Wildlife Disease 55: 576–588.

Hilderbrand, G., D. Gustine, K. Joly, B. Mangipane, W. Leacock, M. Cameron, M. Sorum, L. Mangipane, and J. Erlenbach. 2019. The influence of maternal body size, condition, and age on recruitment of four Alaska brown bear populations. Ursus 29:111–118.

Van Hemert, C., T. J. Spivey, B. D. Uher-Koch, T. A. Atwood, D. R. Sinnett, B. W. Meixell, J. W. Hupp, L. G. Adams, D. D. Gustine, A. M. Ramey, and H. Wan. 2018. Serosurvey of influenza A antibodies in wildlife from Arctic Alaska: limited evidence for exposure among mammals. Journal of Wildlife Diseases 55: 387–398.

Hilderbrand, G., D. Gustine, K. Joly, M. Cameron, M. Sorum, and H. Reynolds. 2019. Brown bear (Ursus arctos) body size, condition, and productivity in the Arctic, 1977–2016. Polar Biology 42:1125–1130.

Rickbeil, G. J. M., J. A. Merkle, G. Anderson, M. P. Atwood, J. P. Beckmann, E. K. Cole, A. B. Courtemanch, S. Dewey, D. D. Gustine, M. J. Kauffman, D. E. McWhirter, T. Mong, K. Proffitt, D. R. Stahler, P. J. White, and A. D. Middleton. 2019. Plasticity in elk migration timing is a response to changing environmental conditions. Global Change Biology: doi:10.1111/gcb.14629.

Mangipane, L. S., J. Belant, B. Mangipane, D. Gustine, and G. Hilderbrand. 2018. Sex-specific variation in denning by brown bears. Mammalian Biology 93:38–44.

Johnson, H. E., D. D. Gustine, T. S. Golden, L. G. Adams, L. S. Parrett, E. A. Lenart, and P. S. Barboza. 2018. NDVI exhibits mixed success in predicting spatiotemporal variation in caribou summer forage quality and quantity. Ecosphere 9:e02461.

Bowen, L., A. K. Miles, S. Waters, D. D. Gustine, K. Joly, and G. V. Hilderbrand. 2018. Using gene transcription to assess ecological and anthropological stressors in brown bears. EcoHealth. doi:10.1007/s10393-017-1287-0

Hilderbrand, G. V., D. D. Gustine, B. A. Mangipane, K. Joly, W. Leacock, L. S. Mangipane, J. A. Erlenbach, M. S. Sorum, M. D. Cameron, J. L. Belant, and T. Cambier. 2018. Body size and lean mass of brown bears across and within four diverse ecosystems. Journal of Zoology 305:53-62. doi:10.1111/jzo.12536

Hilderbrand, G. V., D. D. Gustine, B. A. Mangipane, K. Joly, W. Leacock, L. S. Mangipane, J. A. Erlenbach, M. S. Sorum, M. D. Cameron, J. L. Belant, and T. Cambier. 2018. Plasticity in physiological condition of female brown bears across diverse ecosystems. Polar Biology. doi:10.1007/s00300-017-2238-5

Oster, K., P. Barboza, D. Gustine, K. Joly, and R. Shively. 2018. A spatial and phenological perspective of mineral constraints on arctic caribou. Ecosphere 9: e02160. 10.1002/ecs2.2160.

Barboza, P., L. Van Someren, D. Gustine, and S. Bret-Harte. 2018. The nitrogen window for arctic herbivores: plant phenology and protein gain of migratory caribou (Rangifer tarandus). Ecosphere 9: e02073.

Mangipane, L., J. Belant, D. Lafferty, D. Gustine, T. Hiller, M. Colvin, B. Mangipane, and G. Hilderbrand. 2018. Dietary plasticity in a nutrient-rich system does not influence brown bear (Ursus arctos) body condition or denning. Polar Biology 41:763-772

Mangipane, L., J. Belant, T. Hiller, M. Colvin, D. Gustine, B. Mangipane, and G. Hilderbrand. 2017. Influences of landscape heterogeneity on home-range sizes of brown bears. Mammalian Biology 88: 1–7.

Bled, F., J. L. Belant, L. J. Van Daele, N. Svoboda, D. D. Gustine, G. V. Hilderbrand, and V. G. Barnes. 2017. Using multiple data types and integrated population models to improve our knowledge of apex predator population dynamics. Ecology and Evolution: 1−13.

Deacy, W., J. Armstrong, W. Leacock, C. Robbins, D. Gustine, E. Ward, J. Erlenbach, and J. Stanford. 2017. Phenological synchronization disrupts trophic interactions between Kodiak brown bears and salmon. Proceedings of National Academy of Sciences: doi:10.1073/pnas.1705248114.

VanSomeren, L. L., P. S. Barboza, D. D. Gustine, and M. Syndonia Bret-Harte. 2017. Variation in 15N and 13C values of forages for arctic caribou: effects of location, phenology, and simulated digestion. Rapid Communications in Mass Spectrometry 31: 813–820.

Gustine, D. D., P. S. Barboza, L. G. Adams, B. Griffith, R. Cameron, and K. Whitten. 2017. Advancing the match-mismatch framework for large herbivores in the Arctic: Evaluating the evidence for a trophic mismatch in caribou. PLOS One 12: e0171807.

Tape, K. D., D. D. Gustine, R. W. Ruess, L. G. Adams, and J. A Clark. 2016. Range expansion of moose in Arctic Alaska linked to warming and increased shrub habitat. PLoS ONE 11: e0152636.

VanSomeren, L. L., P. S. Barboza, D. P. Thompson, and D. D. Gustine. 2015. Monitoring the digestibility of forages for herbivores: a new application for an old approach. Canadian Journal of Zoology 93(3): 187–195.

Wilson, R. R., D. D. Gustine, and K. Joly. 2014. Evaluating potential effects of an industrial road on winter habitat of caribou in north-central Alaska. Arctic 67: 472–482.

Tape, K.D., J. M. Pearce, D. Walworth, B. W. Meixell, T. F. Fondell, D. D. Gustine, P. L. Flint, J. W. Hupp, J. A. Schmutz, and D. H. Ward. 2014. Historical and contemporary imagery to assess ecosystem change on the Arctic Coastal Plain of northern Alaska: U.S. Geological Survey Open-File Report 2014–1140, 22 p.

Gustine, D. D., T. Brinkman, M. Lindgren, J. I. Schmidt, T. S. Rupp, and L. G. Adams. 2014. Climate-driven effects of fire on winter habitat for migratory tundra caribou in the Alaskan-Yukon Arctic. PLOS One 9: e100588.

Gustine, D. D., P. S. Barboza, L. G. Adams, and N. B. Wolf. 2014. Environmental and physiological correlates of δ15N and protein status in a montane ungulate. PLOS One 9: e103471.

Gustine, D., P. Barboza, J. Addison, R. Shively, and L. Oliver. 2014. Isotopic N in fecal fiber as an indicator of winter diet in caribou and muskoxen. Rapid Communications in Mass Spectrometry 28:625–634.

Tape, K. D., and D. D. Gustine. 2014. Capturing migration phenology of terrestrial wildlife using camera traps. BioScience 64:117–124.

Gustine, D. D., P. S. Barboza, L. G. Adams, J. P. Lawler, S. Arthur, K. L. Parker, and B. Shults. 2012. Diversity of nitrogen isotopes and correlates of protein status in caribou: implications for monitoring northern ungulates. Journal of Mammalogy 93:778–790.

Milakovic, B., K. L. Parker, D. D. Gustine, R. J. Lay, A. B. D. Walker, and M. P. Gillingham. 2012. Seasonal habitat use and selection by grizzly bears in northern British Columbia. Journal of Wildlife Management 76:170–180.

Gustine, D. D., P. S. Barboza, J. P. Lawler, S. Arthur, B. Shults, K. Persons, and L. G. Adams. 2011. Characteristics of foraging sites and protein status in wintering muskoxen: insights from isotopes of nitrogen. Oikos 120:1546–1556.

Milakovic, B., K. L. Parker, D. D. Gustine, R. J. Lay, A. B. D. Walker, and M. P. Gillingham. 2011. Habitat selection by a focal predator (Canis lupus) in a multi-prey ecosystem of the northern Rockies. Journal of Mammalogy 92:568–582.

Gustine, D. D., P. S. Barboza, L. G. Adams, and R. Farnell. 2011. An isotopic approach to measuring nitrogen balance in caribou. Journal of Wildlife Management 75:178–188.

Gustine, D. D. 2010. Protein status in muskoxen and caribou in late winter. Dissertation, University of Alaska Fairbanks, Fairbanks, AK.

Gustine, D. D., P. S. Barboza, and J. P. Lawler. 2010. Dynamics of body protein and the implications for reproduction in muskoxen (Ovibos moschatus) during winter. Physiological and Biochemical Zoology 83:687–697.

Gustine, D. D., and K. L. Parker. 2008. Variation in the seasonal selection of resources by woodland caribou in northern British Columbia. Canadian Journal of Zoology 86:812–825.

Gustine, D. D., K. L. Parker, and D. C. Heard. 2007. Using ultrasound measurements of back fat to estimate fat reserves of woodland caribou in northern British Columbia, Canada. Rangifer 17:249–256.

Walker, A. B. D., K. L. Parker, M. P. Gillingham, D. D. Gustine, and R. J. Lay. 2007. Habitat selection and movements of Stone’s sheep in relation to vegetation, topography, and the risk of predation. Ecoscience 14:55–70.

Parker, K. L., and D. D. Gustine. 2007. Winter habitat selection and calving strategies of woodland caribou in the Besa-Prophet. Part I: An Ecosystem Approach to Habitat Capability Modeling and Cumulative Effects Management. Report Series (MK-2001-2007) for the Muskwa-Kechika Management Area, Fort St. John, BC.

Gustine, D. D., K. L. Parker, R. J. Lay, M. P. Gillingham, and D. C. Heard. 2006. Calf survival of woodland caribou in a multi-predator ecosystem. Wildlife Monographs 165:1–32.

Gustine, D. D., K. L. Parker, R. J. Lay, M. P. Gillingham, and D. C. Heard. 2006. Interpreting resource selection at different scales for woodland caribou in winter. Journal of Wildlife Management 70:1601–1614.

Gustine, D. D. 2005. Calf survival and resource selection by woodland caribou (Rangifer tarandus caribou) in the Besa-Prophet drainage of northcentral British Columbia. Ministry of Environment, Peace Region. Fort St. John, BC.

Gustine, D. D. 2005. Plasticity in the selection of resources by woodland caribou (Rangifer tarandus caribou) in calving and winter. Thesis, University of Northern British Columbia, Prince George, BC.

Areas of expertise
Human-wildlife conflict management
Nutritional, spatial, and habitat ecology of large mammals