Karyn Rode, Ph.D.
As a Research Wildlife Biologist, I conduct studies focused on the ecology, physiology, and behavior of large mammals to understand their response to environmental change, identify what environmental or ecological factors (e.g., prey availability, winter temperature, ice availability, etc.) most influence whether a population increases, decreases, or is stable, and to maintain positive wildlife-human interactions.
I work with international and bilateral groups, such as the Polar Bear Range States and US-Russia Polar Bear Commission, DOI partners, including U.S. Fish and Wildlife Service, the Bureau of Land Management, and the U.S. National Park Service, Alaska Native co-management groups, and local and state governments to identify and address research needs for polar bears and walruses. My research focuses primarily on identifying biological and ecological indicators for monitoring large mammal populations and ecosystem change and determining mechanisms of population regulation in response to environmental change. I also study wildlife interactions with humans in areas of industry, via tourism and recreation, and in local communities to help minimize or avoid negative effects on wildlife and ensure human safety. Much of my work is centered on nutritional and physiological ecology and its effects on wildlife body condition, reproduction, and survival. Often, I work to develop new methods needed to address information needs. Although all research questions pertain to wild populations, I also regularly conduct studies with animals in zoos and other captive settings where more detailed study of animal physiology and development of new research techniques are possible.
Professional Experience
Mar 2012 - Present Research Wildlife Biologist, USGS Alaska Science Center
Oct 2006 - Feb 2012 Wildlife Biologist, US Fish and Wildlife Service Polar Bear Program, Anchorage, Alaska
Jan 2006 - Oct 2006 Research Associate, Cornell University, Forest Elephant program
June 2002 - Dec 2005 Contract wildlife biologist - Alaska Department of Fish and Game/PhD candidate - Washington State University
Education and Certifications
Ph.D. Washington State University Zoology
M.S. Washington State University Zoology
B.S. Colorado State University Wildlife Biology
Affiliations and Memberships*
2020 - present Vice President- Americas, International Association of Bear Research and Management
2017 - present International Association of Bear Research and Management Grants Review Committee
2017 - present Member of the American Zoological Association’s Polar Bear Research Council
2015 - present Member of Science/TEK working group of the US Fish and Wildlife Service Polar Bear Recovery Team
2009 - 2010 Secretary/Treasurer of the Alaska chapter of the Wildlife Society
2008 - present Member of the International Union for the Conservation of Nature's (IUCN) Polar bear specialist group
2007 - present Member of the Scientific/TEK working group under the US-Russia polar bear commission
Science and Products
Data from a Circumpolar Survey on Recreational Activities in Polar Bear Habitat, 2017-2018
Denning Behavior Classifications Using Temperature Sensor Data on Collars Deployed on Polar Bears in the Southern Beaufort Sea, 1986-2013
Fatty Acid Signature Data of Chukchi Sea Polar Bears, 2008-2015
Summer Activity Sensor Data from Collars Deployed on Female Polar Bears in the Chukchi Sea 1989 to 1995 and Southern Beaufort Sea 1989 to 2014
Stable Isotope Data from Diets and Tissues of Captive Bears Fed Experimental Diets
Recreation Survey Results in Brown Bear Habitats, 2013
Chukchi Sea Polar Bear Locations, 1985-1996
Assessing the robustness of quantitative fatty acid signature analysis to assumption violations (Supplementary data)
New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos)
Long-term variation in polar bear body condition and maternal investment relative to a changing environment
Fatty acid profiles of feeding and fasting bears: Estimating calibration coefficients, the timeframe of diet estimates, and selective mobilization during hibernation
Iñupiaq knowledge of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska
Energetic and health effects of protein overconsumption constrain dietary adaptation in an apex predator
Seal body condition and atmospheric circulation patterns influence polar bear body condition, recruitment, and feeding ecology in the Chukchi Sea
Re-examination of population structure in Arctic ringed seals using DArTseq genotyping
Polar Bear (Ursus maritimus)
Brown Bear (Ursus arctos; North America)
Identifying reliable indicators of fitness in polar bears
Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort and Chukchi Seas and nearby areas, 1910–2018
The clock keeps ticking: Circadian rhythms of free-ranging polar bears
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
- Science
- Data
Filter Total Items: 20
Data from a Circumpolar Survey on Recreational Activities in Polar Bear Habitat, 2017-2018
These data are the responses of researchers, managers, community members, and tour guides who live or work in polar bear habitats anywhere within their range to inquiries about the types, frequency, and potential impacts of recreational activities. Respondents answered a series of questions on their background and experience with polar bears and the geographic area in which they are familiar. RespDenning Behavior Classifications Using Temperature Sensor Data on Collars Deployed on Polar Bears in the Southern Beaufort Sea, 1986-2013
These data include two spreadsheets. The first is average daily temperatures received via satellite transmitting collars deployed on polar bears in the southern Beaufort Sea 1986-2013. The second is denning classifications for adult female polar bears in the southern Beaufort Sea using the temperature data. Denning was classified using a control chart-based algorithm applied to the temperature dFatty Acid Signature Data of Chukchi Sea Polar Bears, 2008-2015
These data were collected to gain insights into the diet composition of Chukchi Sea polar bears. These data were collected to gain insights into the diet composition of Chukchi Sea polar bears.Summer Activity Sensor Data from Collars Deployed on Female Polar Bears in the Chukchi Sea 1989 to 1995 and Southern Beaufort Sea 1989 to 2014
These are data collected from two types of activity sensors housed within collars deployed on female polar bears in the Chukchi and southern Beaufort Seas during the months of July through October between 1989 and 2014. Mercury tip-switches were deployed 1989 to 2009 and accelerometers were deployed 2009-2014. Activity sensor readings were related to habitats used by polar bears as described in thStable Isotope Data from Diets and Tissues of Captive Bears Fed Experimental Diets
This dataset contains stable isotope incorporation and discrimination results for several sets of feeding experiments with captive brown and polar bears. Experiments were designed to determine the effects of dietary lipid content and fasting behavior on discrimination in blood, hair, and fat. Data are divided into three components of the study: one to estimate isotopic discrimination with varyinRecreation Survey Results in Brown Bear Habitats, 2013
These data are the results of a modified Delphi survey in which expert opinion was solicited on the occurrence and frequency of recreational activities in brown bear habitats and their potential impacts. Twelve bear experts were surveyed and identified by either 1) their scientific publications on the impacts of one or more human recreational activity on bears, or 2) their experience in managing bChukchi Sea Polar Bear Locations, 1985-1996
These data are the raw data collected from satellite radio-collars between1985-1996. The collars were worn by adult female polar bears ranging within the Chukchi Sea polar bear subpopulation. The locations of bears were determined by the ARGOS System on-board the collar and were transmitted via the ARGOS system once every 3 days.Assessing the robustness of quantitative fatty acid signature analysis to assumption violations (Supplementary data)
This dataset contains fatty acid (FA) data expressed as mass percent of total FA for bearded seals, ringed seals and walrus. This is one of many datasets used in Bromaghin et al., In press, Assessing the robustness of quantitative fatty acid signature analysis to assumption violations, Methods in Ecology and Evolution. These supplemental data were used in computer simulations to compare the bias o - Multimedia
- Publications
Filter Total Items: 58
New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos)
Although polar bears (Ursus maritimus) and brown bears (U. arctos) have been exhibited in zoological gardens for centuries, little is known about their nutritional needs. Multiple recent studies on both wild and captive polar bears and brown bears have found that they voluntarily select dietary macronutrient proportions resulting in much lower dietary protein and higher fat or digestible carbohydrAuthorsCharles T. Robbins, Troy N Tollefson, Karyn D. Rode, Joy Erlenbach, Amanda J. ArdenteLong-term variation in polar bear body condition and maternal investment relative to a changing environment
In the Arctic, warming air and ocean temperatures have resulted in substantial changes to sea ice, which is primary habitat for polar bears (Ursus maritimus). Reductions in extent, duration, and thickness have altered sea ice dynamics, which influences the ability of polar bears to reliably access marine mammal prey. Because nutritional condition is closely linked to population vital rates, a progAuthorsTodd C. Atwood, Karyn D. Rode, David C. Douglas, Kristin S. Simac, Anthony Pagano, Jeffrey F. BromaghinFatty acid profiles of feeding and fasting bears: Estimating calibration coefficients, the timeframe of diet estimates, and selective mobilization during hibernation
Accurate information on diet composition is central to understanding and conserving carnivore populations. Quantitative fatty acid signature analysis (QFASA) has emerged as a powerful tool for estimating the diets of predators, but ambiguities remain about the timeframe of QFASA estimates and the need to account for species-specific patterns of metabolism. We conducted a series of feeding experimeAuthorsGregory W. Thiemann, Karyn D. Rode, Joy A Erlenbach, Suzanne Budge, Charles T. RobbinsIñupiaq knowledge of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska
Successful wildlife management depends upon coordination and consultation with local communities. However, much of the research used to inform management is often derived solely from data collected directly from wildlife. Indigenous people living in the Arctic have a close connection to their environment, which provides unique opportunities to observe their environment and the ecology of Arctic spAuthorsKaryn D. Rode, Hannah Voorhees, Henry P. Huntington, George M. DurnerEnergetic and health effects of protein overconsumption constrain dietary adaptation in an apex predator
Studies of predator feeding ecology commonly focus on energy intake. However, captive predators have been documented to selectively feed to optimize macronutrient intake. As many apex predators experience environmental changes that affect prey availability, limitations on selective feeding can affect energetics and health. We estimated the protein:fat ratio of diets consumed by wild polar bears usAuthorsKaryn D. Rode, Charles T. Robbins, Craig A. Stricker, Brian D. Taras, Troy N TollefsonSeal body condition and atmospheric circulation patterns influence polar bear body condition, recruitment, and feeding ecology in the Chukchi Sea
Polar bears (Ursus maritimus) are experiencing loss of sea ice habitats used to access their marine mammal prey. Simultaneously, ocean warming is changing ecosystems that support marine mammal populations. The interactive effects of sea ice and prey are not well understood yet may explain spatial‐temporal variation in the response of polar bears to sea ice loss. Here, we examined the potential comAuthorsKaryn D. Rode, Eric V. Regehr, Jeffrey F. Bromaghin, Ryan H. Wilson, Michelle St. Martin, Justin A. Crawford, Lori T. QuakenbushRe-examination of population structure in Arctic ringed seals using DArTseq genotyping
Although Arctic ringed seals Phoca hispida hispida are currently abundant and broadly distributed, their numbers are projected to decline substantially by the year 2100 due to climate warming. While understanding population structure could provide insight into the impact of environmental changes on this subspecies, detecting demographically important levels of exchange can be difficult in taxa witAuthorsAimee R. Lang, Peter L. Boveng, L. Quakenbush, K. Robertson, M. Lauf, Karyn D. Rode, H. Ziel, B .L. TaylorPolar Bear (Ursus maritimus)
This chapter comprises the following sections: names, taxonomy, subspecies and distribution, descriptive notes, habitat, movements and home range, activity patterns, feeding ecology, reproduction and growth, behavior, parasites and diseases, status in the wild, and status in captivity.AuthorsKaryn D. Rode, Martyn E. Obbard, Stanislav Belikov, Andrew E. Derocher, George M. Durner, Gregory Thiemann, Morten Tryland, Robert J. Letcher, Randi Meyersen, Christian Sonne, Bjorn Jenssen, Rune Dietz, Dag VongravenBrown Bear (Ursus arctos; North America)
This chapter comprises the following sections: names, taxonomy, subspecies and distribution, descriptive notes, habitat, movements and home range, activity patterns, feeding ecology, reproduction and growth, behavior, parasites and diseases, status in the wild, and status in captivity.AuthorsMark A. Haroldson, Melanie Clapham, Cecily M. Costello, Kerry A. Gunther, Kate Kendall, Sterling Miller, Karine Pigeon, Michael F. Proctor, Karyn D. Rode, Christopher Servheen, Gordon Stenhouse, Frank T. van ManenIdentifying reliable indicators of fitness in polar bears
Animal structural body size and condition are often measured to evaluate individual health, identify responses to environmental change and food availability, and relate food availability to effects on reproduction and survival. A variety of condition metrics have been developed but relationships between these metrics and vital rates are rarely validated. Identifying an optimal approach to estimateAuthorsKaryn D. Rode, Todd C. Atwood, Gregory Thiemann, Michelle St. Martin, Ryan H. Wilson, George M. Durner, Eric V. Regehr, Sandra L. Talbot, Kevin Sage, Anthony M. Pagano, Kristin S. SimacCatalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort and Chukchi Seas and nearby areas, 1910–2018
This report presents data on the approximate locations and methods of discovery of 530 polar bear (Ursus maritimus) maternal dens observed in the Beaufort and Chukchi Seas and neighboring areas from 1910 to 2018, and archived partly by the U.S. Geological Survey, Alaska Science Center, and partly by the U.S. Fish and Wildlife Service, Marine Mammals Management, in Anchorage, Alaska. A descriptionAuthorsGeorge M. Durner, Steven C. Amstrup, Todd C. Atwood, David C. Douglas, Anthony S. Fischbach, Jay W. Olson, Karyn D. Rode, Ryan H. WilsonThe clock keeps ticking: Circadian rhythms of free-ranging polar bears
Life in the Arctic presents organisms with multiple challenges, including extreme photic conditions, cold temperatures, and annual loss and daily movement of sea ice. Polar bears (Ursus maritimus) evolved under these unique conditions, where they rely on ice to hunt their main prey, seals. However, very little is known about the dynamics of their daily and seasonal activity patterns. For many orgaAuthorsJasmine V. Ware, Karyn D. Rode, Charles T. Robbins, T. Leise, C.R. Weil, Heiko T. JansenNon-USGS Publications**
Voorhees, H., R. Sparks, H. P. Huntington, and K. D. Rode. 2014. Traditional knowledge of polar bears (Ursus maritimus) in Northwestern Alaska. Arctic 67(4):523-436. doi:10.14430/arctic4425.Erlenbach, J. A., K. D. Rode, D. Raubenheimer, and C. M. Robbins. 2014. Macronutrient optimization and energy maximization determine diets of brown bears. Journal of Mammalogy 95(1):160-168. doi:10.1644/13-MAMM-A-161.Robbins, C. T., C. Lopez-Alfaro, K. D. Rode, Ø. Tøien, and O. L. Nelson. 2012. Hibernation and seasonal fasting in bears: the energetic costs and consequences for polar bears. Journal of Mammalogy 93(6):1493-1503. doi:10.1644/11-MAMM-A-406.1.Whiteman, J. P., K. A. Greller, H. J. Harlow, L. A. Felicetti, K. D. Rode, and M. Ben-David. 2012. Carbon isotopes in exhaled breath track metabolic substrates in brown bears (Ursus arctos). Journal of Mammalogy 93:413-421. doi:10.1644/11-MAMM-S-178.1.Gleason, J. S. and K. D. Rode. 2009. Polar bear distribution and habitat association reflect long-term changes in fall sea ice conditions in the Alaskan Beaufort Sea. Arctic 62(4):405-417.Schliebe, S. L., K. D. Rode, J. S. Gleason, J. Wilder, K. M. Proffitt, T. J. Evans, and S. Miller. 2008. Effects of sea ice extent and food availability on spatial and temporal distribution of polar bears during the fall open-water period in the Southern Beaufort Sea. Polar Biology 31(8):999-1010. doi:10.1007/s00300-008-0439-7.Stirling, I., A. E. Derocher, W. Gough, and K. D. Rode. 2008. Response to Dyck et al. (2007) on polar bears and climate change in western Hudson Bay. Ecological Complexity 5(3):193-201. doi:10.1016/j.ecocom.2008.01.004.Rode, K. D., S. C. Amstrup, and E. V. Regehr. 2007. Polar bears in the southern Beaufort Sea III: Stature, mass, and cub recruitment in relationship to time and sea ice extent between 1982 and 2006. USGS Administrative Report, 31 p.Robbins, C. T., J. K. Fortin, K. D. Rode, S. D. Farley, L. A. Shipley, and L. A. Felicetti. 2007. Optimizing protein intake as a foraging strategy to maximize mass gain in an omnivore. Oikos 116(10):1675-1682. doi:10.1111/j.0030-1299.2007.16140.x.Fortin, J. K., S. D. Farley, C. T. Robbins, and K. D. Rode. 2007. The role of salmon and berries in determining fall weight gains in brown bears. Ursus 18(1):19-29. doi:10.2192/1537-6176(2007)18[19:DASOBS]2.0.CO;2.Rode, K. D., S. D. Farley, and C. T. Robbins. 2006. Behavioral responses of brown bears mediate nutritional impacts of experimentally introduced tourism. Biological Conservation 133(1):70-80. doi:10.1016/j.biocon.2006.05.021.Rode, K. D., C. A. Chapman, L. D. McDowell, and C. A. Stricker. 2006. Nutritional mechanisms of population regulation across habitats and logging intensities in redtail monkeys (Cercopithecus ascanius). Biotropica 38:625-634. doi:10.1111/j.1744-7429.2006.00183.x.Rode, K. D., P. I. Chiyo, C. A. Chapman, and L. D. McDowell. 2006. Nutritional ecology of elephants in Kibale National Park, Uganda, and its relationship with crop raiding behaviour. Journal of Tropical Ecology 22(4):441-449. doi:10.1017/S0266467406003233. https://doi.org/10.1017/S0266467406003233
Rode, K. D., S. D. Farley, and C. T. Robbins. 2006. Sexual dimorphism, reproductive strategy, and human activities determine resource use by brown bears. Ecology 87(10):2636-2646. doi:10.1890/0012-9658(2006)87[2636:SDRSAH]2.0.CO;2.Danish, L., C. A. Chapman, C. O'Driscoll Worman, K. D. Rode, and M. B. Hall. 2006. The role of sugar content in diet selection in redtail and red colobus monkeys. In Feeding Ecology in apes and other primates. Cambridge University Press, UK.Chapman, C. A., L. J. Chapman, K. D. Rode, and L. D. McDowell. 2003. Variation in the nutritional value of primate foods: Among trees, time periods, and areas. International Journal of Primatology 24(2):317-337. doi:10.1023/A:1023049200150.Rode, K. D., C. A. Chapman, L. J. Chapman, and L. D. McDowell. 2003. Mineral resource availability and consumption by colobus monkeys in Kibale National Park, Uganda. International Journal of Primatology 24(3):541-573. doi:10.1023/A:1023788330155.Chapman, C. A., L. J. Chapman, M. Cords, M. Gauthua, A. Gautier-Hion, J. E. Lambert, K. D. Rode, C. E. G. Tutin, and L. J. T. White. 2002. Variation in the Diets of Cercopithecus Species: Differences Within Forests, Among Forests, and Across Species. In The Guenons: Diversity and Adaptation in African Monkeys. M. Glenn and M. Cords (eds.). Plenum Press New York City, NY, USA.Rode, K. D., C. T. Robbins, and L. A. Shipley. 2001. The constraints on herbivory by bears. Oecologia 128(1):62-71. doi:10.1007/s004420100637.Rode, K. D. and C. T. Robbins. 2000. Why bears consume mixed diets during fruit abundance. Canadian Journal of Zoology 78(9):1-6. doi:10.1139/z00-082.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government