Algeo, T. P., D. Slate, R. M. Caron, T. C. Atwood, S. Recuenco, M. Ducey, R. B. Chipman, and M. Palace. 2017. Modeling raccoon (Procyon lotor) habitat connectivity to identify potential corridors for rabies spread. Tropical Medicine and Infectious Diseases 44. doi:10.3390/tropicalmed203044.
Todd Atwood, Ph.D.
Spatial ecology, population ecology, predator-prey dynamics, polar bear ecology
Biography
Education
Ph.D. 2006 Utah State University Wildlife Biology
M.S. 2002 Purdue University Wildlife Ecology
B.S. 1999 Purdue University Wildlife Ecology
Professional Experience
2012 - Present Research Wildlife Biologist and Project Leader, USGS Alaska Science Center, Anchorage, AK
2008 - 2012 Research Wildlife Biologist, USDA/APHIS/WS/National Wildlife Research Center, Fort Collins, CO
2006 - 2008 Research Biologist, Research Branch, Arizona Game and Fish Department, Phoenix, AZ
2006 Biological Technician, USDA/National Wildlife Research Center, Fort Collins, CO
Professional Activities and/or Memberships
The Wildlife Society
International Association for Bear Research and Management
American Society of Mammalogists
Science and Products
Date published: December 18, 2017
Status: Active Polar Bear Maternal Denning
Pregnant polar bears enter maternity dens in October/November, give birth to cubs in December/January, and exit dens in March/April. Historically, most polar bears from the Southern Beaufort Sea (SBS) population constructed maternity dens on the sea ice. Over the last three decades, as sea ice has become thinner and prone to fragmentation, there has been a landward shift in the distribution...
Contacts: Todd Atwood, Ph.D., George Durner, Ph.D.
Date published: December 15, 2017
Status: Active Distribution and Movements of Polar Bears
Polar bears are tied to the sea ice for nearly all of their life cycle functions. Most important of these is foraging, or access to food. Polar bears almost exclusively eat seals, and they are equally as dependent upon the sea for their nutrition as are seals, whales, and other aquatic mammals. Polar bears are not aquatic, however, and their only access to the seals is from the surface of the...
Attribution: Region 11: Alaska, Alaska Science Center
Date published: December 15, 2017
Status: Active Polar Bear Population Dynamics
Information on the status and trends of polar bear populations are needed to inform management of polar bears under US laws and international agreements. The USGS maintains a long-term research program focused on the population dynamics of the southern Beaufort Sea polar bear population. In addition, the USGS collaborates with the US Fish and Wildlife Service in population studies in the...
Attribution: Region 11: Alaska, Alaska Science Center
Date published: December 15, 2017
Status: Active Health and Energetics of Polar Bears
Research in this focal area is centered on (i) collecting data on a variety of systems that help determine and mediate polar bear health and energetics, and (ii) developing monitoring and surveillance programs for detecting changes in population health over time. Additionally, this work will allow us to develop an understanding of how polar bear populations will respond to a variety of...
Attribution: Region 11: Alaska, Alaska Science Center
Date published: July 13, 2017
Status: Active Polar Bear Research
Polar bears (Ursus maritimus) are one of 4 marine mammal species managed by the U.S. Department of Interior. The USGS Alaska Science Center leads long–term research on polar bears to inform local, state, national and international policy makers regarding conservation of the species and its habitat. Our studies, ongoing since 1985, are focused on population dynamics, health and...
Attribution: Ecosystems, Energy & Wildlife, Wildlife Program, Region 11: Alaska, Alaska Science Center
Year Published: 2021
Human-polar bear interactions
Human-wildlife interactions (HWI) are driven fundamentally by overlapping space and resources. As competition intensifies, the likelihood of interaction and conflict increases. In turn, conflict may impede conservation efforts by lowering social tolerance of wildlife, especially when human-wildlife conflict (HWC) poses a threat to human safety and...
Davis, Randall W.; Pagano, Anthony M.; Atwood, Todd C.; Wilder, James
Year Published: 2021
Measuring adrenal and reproductive hormones in hair from southern Beaufort Sea polar bears (Ursus maritimus)
Polar bears (Ursus maritimus) use sea ice to access marine mammal prey. In Alaska’s Southern Beaufort Sea, the declining availability of sea ice habitat in summer and fall has reduced opportunities for polar bears to routinely hunt on the ice for seals, their primary prey. This reduced access to prey may result in physiological stress with...
Van der Walt, Marilize; Neuman-Lee, Lorin; Terletzky, Patricia; Atwood, Todd C.; Gese, Eric; French, Susannah
Year Published: 2020
How Is climate change affecting polar bears and giant pandas?
Anthropogenic greenhouse gas emissions are the primary cause of climate change and an estimated increase of 3.7 to 4.8 °C is predicted by the year 2100 if emissions continue at current levels. Polar bears (Ursus maritimus) and giant pandas (Ailuropoda melanoleuca) provide an interesting comparison study of the impact of climate change on bear...
Songer, Melissa; Atwood, Todd C.; Douglas, David C.; Huang, Qiongyu; Li, Renqiang; Pilfold, Nicholas; Xu, Ming; Durner, George M.
Year Published: 2020
Analyses on subpopulation abundance and annual number of maternal dens for the U.S. Fish and Wildlife Service on polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska
The long-term persistence of polar bears (Ursus maritimus) is threatened by sea-ice loss due to climate change, which is concurrently providing an opportunity in the Arctic for increased anthropogenic activities including natural resource extraction. Mitigating the risk of those activities, which can adversely affect the population dynamics of the...
Atwood, Todd C.; Bromaghin, Jeffrey F.; Patil, Vijay P.; Durner, George M.; Douglas, David C.; Simac, Kristin S.View Citation
Atwood, T.C., Bromaghin, J.F., Patil, V.P., Durner, G.M., Douglas, D.C., and Simac, K.S., 2020, Analyses on subpopulation abundance and annual number of maternal dens for the U.S. Fish and Wildlife Service on polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska: U.S. Geological Survey Open-File Report 2020-1087, 16 p., https://doi.org/10.3133/ofr20201087.
Year Published: 2020
Identifying 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...
Rode, Karyn D.; Atwood, Todd C.; Thiemann, Gregory; St. Martin, Michelle; Wilson, Ryan R.; Durner, George M.; Regehr, Eric V.; Talbot, Sandra L.; Sage, Kevin; Pagano, Anthony M.; Simac, Kristin S.
Year Published: 2020
Fatty acid-based diet estimates suggest ringed seal remain the main prey of southern Beaufort Sea polar bears despite recent use of onshore food resources
Polar bears (Ursus maritimus) from the southern Beaufort Sea (SB) subpopulation have traditionally fed predominantly upon ice‐seals; however, as the proportion of the subpopulation using onshore habitat has recently increased, foraging on land‐based resources, including remains of subsistence‐harvested bowhead whales (Balaena mysticetus) and...
Bourque, Jennifer; Atwood, Todd C.; Divoky, George J.; Stewart, Connie; McKinney, Melissa A.
Year Published: 2020
Catalogue 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...
Durner, George M.; Amstrup, Steven C.; Atwood, Todd C.; Douglas, David C.; Fischbach, Anthony S.; Olson, Jay W.; Rode, Karyn D.; Wilson, Ryan R.View Citation
Durner, G.M., Amstrup, S.C., Atwood, T.C., Douglas, D.C., Fischbach, A.S., Olson, J.W., Rode, K.D., and Wilson, R.R., 2020, Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort and Chukchi Seas and nearby areas, 1910–2018: U.S. Geological Survey Data Series 1121, 12 p., including appendixes, https://doi.org/10.3133/ds1121. [Supersedes USGS Data Series 568.]
Year Published: 2020
Global change-driven use of onshore habitat impacts polar bear faecal microbiota
The gut microbiota plays a critical role in host health, yet remains poorly studied in wild species. Polar bears (Ursus maritimus), key indicators of Arctic ecosystem health and environmental change, are currently affected by rapid shifts in habitat that may alter gut homeostasis. Declining sea ice has led to a divide in the southern Beaufort Sea...
Watson, Sophie; Hauffe, Heidi; Bull, Matthew; Atwood, Todd C.; McKinney, Melissa; Pindo, Massimo; Perkins, Sarah
Year Published: 2019
The seasonal energetic landscape of an apex marine carnivore, the polar bear
Divergent movement strategies have enabled wildlife populations to adapt to environmental change. In recent decades, the Southern Beaufort Sea subpopulation of polar bears (Ursus maritimus) has developed a divergent movement strategy in response to diminishing sea ice where the majority of the subpopulation (73–85%) stays on the sea ice in summer...
Pagano, Anthony M.; Atwood, Todd C.; Durner, George M.; Williams, Terrie M.
Year Published: 2019
Use of subsistence-harvested whale carcasses by polar bears in the southern Beaufort Sea
The availability of a food subsidy has the potential to influence the condition, behavior, fitness, and population dynamics of a species. Since the early 2000s, monitoring efforts along the coast of northern Alaska indicated a higher proportion of polar bears (Ursus maritimus) of the southern Beaufort Sea (SB) subpopulation come onshore and feed...
Lillie, Kate M; Gese, Eric M; Atwood, Todd C.; Conner, Mary M
Year Published: 2019
Reference intervals for blood-based biochemical analytes of southern Beaufort Sea polar bears
Accurate reference intervals (RI) for commonly measured blood-based analytes are essential for health monitoring programs. Baseline values for a panel of analytes can be used to monitor physiologic and pathophysiologic processes such as organ function, electrolyte balance, and protein catabolism. Our reference population includes 651 serum...
Fry, Tricia; Friedrichs, Kristen R.; Atwood, Todd C.; Duncan, Colleen G.; Simac, Kristin S.; Goldberg, Tony
Year Published: 2019
Are polar bear habitat resource selection functions developed from 1985-1996 data still useful?
1. Greenhouse gas-induced warming in the Arctic has caused declines in sea ice extent and changed its composition, raising concerns by all circumpolar nations for polar bear conservation. 2. Negative impacts have been observed in three well-studied polar bear subpopulations. Most subpopulations, however, receive little or no direct monitoring,...
Durner, George M.; Douglas, David C.; Atwood, Todd C.Pre-USGS Publications
Atwood, T. C., E. Peacock, K. M. Lillie, R. R. Wilson, and S. Miller. 2015. Demographic composition and behavior of polar bears summering on shore in Alaska. USGS Administrative Report, 26 p.
Beasley, J. C., T. C. Atwood, M. E. Byrne, K. C. VerCauteren, S. R. Johnson, and O. E. Rhodes, Jr. 2015. A behaviorally-explicit approach for evaluating vaccine baits to mesopredators to control epizootics in fragmented landscapes. PLoS One 10:e0113206. doi:10.1371/journal.pone.0113206.
Anderson, A., S. A. Shwiff, R. B. Chipman, T. C. Atwood, T. Cozzens, F. Fillo, R. Hale, B. Hatch, J. Maki, O. E. Rhodes, Jr, E. E. Rees, C. E. Rupprecht, R. Tinline, K. C. VerCauteren, and D. Slate. 2014. Forecasting the spread of raccoon rabies using a purpose-specific group decision-making process. Human-Wildlife Interactions 8(1):130-138.
Slate, D., R. B. Chipman, T. P. Algeo, S. A. Mills, K. M. Nelson, C. K. Croson, E. J. Dubovi, R. W. Renshaw, K. C. VerCauteren, T. C. Atwood, S. Johnson, and C. E. Rupprecht. 2014. Safety and immunogenicity in the first field trial with ONRAB in raccoons in the United States. Journal of Wildlife Diseases 50(3):582-595. doi:10.7589/2013-08-207.
Kunkel, K. E., T. K. Ruth, T. C. Atwood, D. H. Pletscher, and M. G. Hornocker. 2013. Assessing the value of wolves and cougars as conservation surrogates by linking carnivore hunting success with landscape characteristics. Animal Conservation 16:32-40. doi:10.1111/j.1469-1795.2012.00568.x.
Beasley, J. D., W. S. Beatty, T. C. Atwood, S. Johnson, and O. E. Rhodes, Jr. 2012. A comparison of methods for estimating raccoon abundance: Implications for disease vaccination programs. Journal of Wildlife Management 76(6):1290-1297. doi:10.1002/jwmg.379.
Atwood, T. C. and S. W. Breck. 2012. Carnivores, Conflict, and Conservation: Defining the Landscape of Conflict. Pages 99-118 in F. I. Álvares and G. E. Mata, (eds.). Carnivores: Species, Conservation, and Management. Nova Publishers.
Partitioning of a limited resource by sympatric carnivores in the Chihuahuan Desert and the implications for disease transmission
Atwood, T. C., T. L. Fry, and B. R. Leland. 2011. Partitioning of a limited resource by sympatric carnivores in the Chihuahuan Desert and the implications for disease transmission. Journal of Wildlife Management 75:1609-1615.
Atwood, T. C., J. K. Young, J. P. Beckmann, S. W. Breck, O. E. Rhodes, Jr, J. A. Fike, and K. D. Bristow. 2011. Modeling connectivity of black bears in a desert sky island archipelago. Biological Conservation 144(12):2851-2862. doi:10.1016/j.biocon.2011.08.002.
Utility of rhodamine B as a biomarker in raccoons
Fry, T. L., T. C. Atwood, and M. R. Dunbar. 2010. Utility of rhodamine B as a biomarker in raccoons. Human-Wildlife Interactions 4:275-282.
Importance of resource selection and social behaviour to partitioning of hostile space by sympatric canids
Atwood, T. C. and E. M. Gese. 2010. Importance of resource selection and social behaviour to partitioning of hostile space by sympatric canids. Journal of Mammalogy 91:490-499.
Raccoon spatial ecology related to cattle and bovine tuberculosis
Atwood, T. C., T. J. DeLiberto, H. J. Smith, J. Stevenson, and K. C. VerCauteren. 2009. Raccoon spatial ecology related to cattle and bovine tuberculosis. Journal of Wildlife Management 73:647-654.
Spatial decomposition of predation risk in a multiple-predator multiple-prey system
Atwood, T. C., E. M. Gese, and K. E. Kunkel. 2009. Spatial decomposition of predation risk in a multiple-predator multiple-prey system. Journal of Wildlife Management 73:876-884.
Coyotes (Canis latrans) and recolonizing wolves (Canis lupus): Social rank mediates risk-conditional behaviour at ungulate carcasses
Atwood, T. C. and E. M. Gese. 2008. Coyotes (Canis latrans) and recolonizing wolves (Canis lupus): Social rank mediates risk-conditional behaviour at ungulate carcasses. Animal Behaviour 75:753-762.
Sentinel-based surveillance of coyotes to detect bovine tuberculosis in Michigan
VerCauteren, K. C., T. C. Atwood, T. J. DeLiberto, H. J. Smith, J. Stevenson, T. Gidlewski, and B. V. Thomsen. 2008. Sentinel-based surveillance of coyotes to detect bovine tuberculosis in Michigan. Emerging Infectious Diseases 14:1862-1869.
Coyotes as a potential sentinel species to detect bovine tuberculosis (Mycobacterium bovis) infection in white-tailed deer in Michigan
Atwood, T. C., K. C. VerCauteren, T. J. DeLiberto, H. J. Smith, and J. Stevenson. 2007. Coyotes as a potential sentinel species to detect bovine tuberculosis (Mycobacterium bovis) infection in white-tailed deer in Michigan. Journal of Wildlife Management 71:1545-1554.
Comparative patterns of predation by cougars and recolonizing wolves
Atwood, T. C., E. M. Gese, and K. E. Kunkel. 2007. Comparative patterns of predation by cougars and recolonizing wolves. Journal of Wildlife Management 71:1098-1106.
The influence of habitat patch attributes on coyote group size and interaction in a fragmented landscape
Atwood, T. C. 2006. The influence of habitat patch attributes on coyote group size and interaction in a fragmented landscape. Canadian Journal of Zoology 84:80-87.
Behavioral interactions between wolves, Canis lupus, and coyotes, Canis latrans, at ungulate carcasses in southwest Montana
Atwood, T. C. 2006. Behavioral interactions between wolves, Canis lupus, and coyotes, Canis latrans, at ungulate carcasses in southwest Montana. Western North American Naturalist 66:390-394.
Spatial ecology of coyotes along a suburban-to-rural gradient
Atwood, T. C., H. P. Weeks, Jr., and T. M. Gehring. 2004. Spatial ecology of coyotes along a suburban-to-rural gradient. Journal of Wildlife Management 85:1000-1009.
Patch occupancy in North American mammals: Is patchiness in the eye of the beholder?
Swihart, R. K., T. C. Atwood, J. R. Goheen, D. A. Scheiman, K. E. Munroe, and T. M. Gehring. 2003. Patch occupancy in North American mammals: Is patchiness in the eye of the beholder? . Journal of Biogeography 30:1259-1279.
Sex-specific patterns of mineral lick preference in white-tailed deer
Atwood, T. C. and H. P. Weeks, Jr.. 2003. Sex-specific patterns of mineral lick preference in white-tailed deer. Northeastern Naturalist 10:409-414.
Sex-and age-specific patterns of mineral lick use by white-tailed deer
Atwood, T. C. and H. P. Weeks, Jr.. 2002. Sex- and age-specific patterns of mineral lick use by white-tailed deer. American Midland Naturalist 148:289-296.
Facultative dyad formation in adult male coyotes
Atwood, T. C. and H. P. Weeks, Jr.. 2002. Facultative dyad formation in adult male coyotes. Northeastern Naturalist 9:353-358.
Date published: June 29, 2016
Polar Bear Outlook Favorable Under Certain Scenarios
“The scenarios predicted by our models are encouraging in that there are clear actions that humans can take to improve the chances that healthy polar bear populations persist in the future.” - Todd Atwood, USGS
Attribution: Region 11: Alaska, Alaska Science Center
Date published: July 9, 2014
Observing Polar Bears from Space
Monitoring wildlife in the Arctic is difficult. Study areas are cold, barren and often inaccessible. For decades scientists have struggled to study animals, like polar bears, which live in these remote areas. Now researchers at the U.S. Geological Survey have begun testing a new, yet counterintuitive solution – rather then get close to the animals, monitor them from afar.
Attribution: Region 11: Alaska