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Anthony M Pagano, Ph.D.

Ecophysiology, spatial ecology, and behavior of large mammals

Professional Experience

  • 2022 - Present     Research Wildlife Biologist     USGS Alaska Science Center, Anchorage, Alaska

  • 2021 - 2022          Post-doctoral Researcher        Washington State University, Pullman, Washington

  • 2018 - 2021          Post-doctoral Researcher        Institute for Conservation Research, San Diego Zoo Wildlife Alliance, Escondido, California

  • 2008 - 2018         Wildlife Biologist                       USGS Alaska Science Center, Anchorage, Alaska

Education and Certifications

  • Ph.D.   2018   University of California, Santa Cruz      Ecology and Evolutionary Biology

  • M.S.    2007   University of Minnesota, St. Paul, MN   Wildlife Conservation

  • B.A.    2002   Northeastern University, Boston, MA     Biology and History

Science and Products

link
A polar bear walks across rubble ice in the Alaska portion of the southern Beaufort Sea

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 sea...
By
Species Management Research Program, Alaska Science Center
link

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 sea...
Learn More
link
Polar bear still hunting at a seal breathing hole

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 stressors...
By
Species Management Research Program, Alaska Science Center
link

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 stressors...
Learn More
link
Polar bear mother and two cubs on the Beaufort Sea ice.

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 energetics...
By
Ecosystems Mission Area, Land Management Research Program, Species Management Research Program, Alaska Science Center
link

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 energetics...
Learn More

Polar Bear Continuous Time-Correlated Random Walk (CTCRW) Location Data Derived from Satellite Location Data, Chukchi and Beaufort Seas, July-November 1985-2017

his dataset consists of one table with estimated locations of adult female polar bears during July-November 1985-2017, used for quantifying changes in summer land use over time. Locations were estimated with a Continuous Time-Correlated Random Walk (CTCRW) model fit to satellite tracking from radio-collared adult female polar bears. All bears included in this data set were captured and instrumente
By
Alaska Science Center

Polar Bear Continuous Time-Correlated Random Walk (CTCRW) Location Data Derived from Satellite Location Data, Southern Beaufort Sea, 1986-2016

This dataset consists of one table with predicted locations of adult female polar bears. Locations were derived by a Continuous Time-Correlated Random Walk (CTCRW) model using satellite tracking radio-collared adult female polar bears captured and instrumented in the southern Beaufort Sea, 1986–2016.
By
Alaska Science Center

Serum Urea and Creatinine Levels of Spring-Caught Polar Bears (Ursus maritimus) in the Southern Beaufort and Chukchi Seas

These data are serum urea nitrogen and creatinine levels for polar bears captured in the southern Beaufort Sea 1983-2016 and the Chukchi Sea 1987-1993 and 2008-2017. The dataset includes relevant information about the bears that were captured including the latitude and longitude of their capture location, capture date, age class and sex, the age and number of cubs accompanying an adult female, and
By
Alaska Science Center

Satellite Location and Tri-axial Accelerometer Data from Adult Female Polar Bears (Ursus maritimus) in the Southern Beaufort Sea, April-October 2014

These data are from 5 adult female polar bears instrumented in the southern Beaufort Sea, April to October 2014. The dataset is comprised of two data packages: 1) contains GPS and Argos locations collected by satellite-linked GPS receivers mounted on external collars, and 2) contains archival logger data including measures of tri-axial acceleration and conductivity. These data were collected to ga
By
Alaska Science Center

Locations Collected 1985-2015 from Female Polar Bears (Ursus maritimus) with Dependent Young Instrumented in the Southern Beaufort Sea with Satellite-linked Transmitters by the USGS

This dataset contains a select subset of Argos and GPS locations collected by satellite data collection systems from collared adult female polar bears that were instrumented in the southern Beaufort Sea between 1985-2015. These data were collected to gain insights into movements of southern Beaufort Sea polar bears. These data were collected from adult female polar bears who had dependent young at
By
Alaska Science Center

Bioelectrical Impedance, Deuterium Dilution, Body Mass, and Morphological Measures of Southern Beaufort Sea Female Polar Bears, Spring 2014-2016

This dataset contains data from the use of bioelectrical impedance analysis and deuterium injection as methods to estimate the body composition of female polar bears in the southern Beaufort Sea subpopulation. Data are provided on bioelectrical impedance resistance measures, the enrichment level of deuterium oxide that was injected and measured in blood samples, and morphological measures.
By
Alaska Science Center

Metabolic Rate, Body Composition, Foraging Success, Behavior, and GPS Locations of Female Polar Bears (Ursus maritimus), Beaufort Sea, Spring, 2014-2016 and Resting Energetics of an Adult Female Polar Bear

This data release comprises 4 datasets used to measure the field metabolic rate, body composition, foraging success, behavior, and movement patterns of 9 female polar bears on the sea ice of the Beaufort Sea in April, 2014-2016 as well as 1 dataset used to measure the energetic cost of resting in an adult female polar bear at the San Diego Zoo, San Diego, CA. Wild bears were dosed with and had the
By
Alaska Science Center

Measures of oxygen consumption and stroke frequency of a captive subadult polar bear (Ursus maritimus) while resting in water and swimming and diving in a metabolic water flume, Oregon Zoo, 2017

This dataset contains measures of oxygen consumption and stroke frequency from 1 captive subadult female polar bear (166.5 kg) resting in the water (n = 7 sessions) and swimming and diving in a metabolic swim flume with water circulated at approximately 0.6 km/hr during swimming and diving measurements (n = 6 sessions) in September 2017.
By
Alaska Science Center
Filter Total Items: 22

Observed and forecasted changes in land use by polar bears in the Beaufort and Chukchi Seas, 1985–2040

Monitoring changes in the distribution of large carnivores is important for managing human safety and supporting conservation. Throughout much of their range, polar bears (Ursus maritimus) are increasingly using terrestrial habitats in response to Arctic sea ice decline. Their increased presence in coastal areas has implications for bear-human conflict, inter-species interactions, and polar bear h
By
Ecosystems Mission Area, Alaska Science Center

Effects of sea ice decline and summer land use on polar bear home range size in the Beaufort Sea

Animals responding to habitat loss and fragmentation may increase their home ranges to offset declines in localized resources or they may decrease their home ranges and switch to alternative resources. In many regions of the Arctic, polar bears (Ursus maritimus) exhibit some of the largest home ranges of any quadrupedal mammal. Polar bears are presently experiencing a rapid decline in Arctic sea i
By
Ecosystems Mission Area, Alaska Science Center

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 economic well-being. Thus, mitigating conflict is
By
Ecosystems Mission Area, Alaska Science Center

Polar bear foraging behavior

Polar bears forage in the marine environment, primarily on the sea ice over the shallow waters of the continental shelf. They are solitary, ambush hunters that catch ringed and bearded seals when they surface to breathe in ice holes or haul out on the ice to rest and molt. In most parts of their range, polar bears experience dramatic seasonal variability in their ability to catch seals, with forag
By
Ecosystems Mission Area, Alaska Science Center

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 validated. Identifying an optimal approach to estimate
By
Ecosystems Mission Area, Alaska Science Center, Molecular Ecology Laboratory

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 and the remaining bears move to land. Although decl
By
Ecosystems Mission Area, Alaska Science Center

Overhauling ocean spatial planning to improve marine megafauna conservation

Tracking data have led to evidence-based conservation of marine megafauna, but a disconnect remains between the many thousands of individual animals that have been tracked and the use of these data in conservation and management actions. Furthermore, the focus of most conservation efforts is within Exclusive Economic Zones despite the ability of these species to move thousands of kilometres across
By
Ecosystems Mission Area, Alaska Science Center

Energetic costs of aquatic locomotion in a subadult polar bear

Most marine mammals rely on swimming as their primary form of locomotion. These animals have evolved specialized morphologies, physiologies, and behaviors that have enabled them to efficiently move through an aquatic environment (Williams 1999). Such adaptations include body streamlining, modified plantar surfaces for propulsion, and abilities to remain submerged for extended durations (Williams 1
By
Ecosystems Mission Area, Alaska Science Center

Estimating the energy expenditure of free‐ranging polar bears using tri‐axial accelerometers: A validation with doubly labeled water

Measures of energy expenditure can be used to inform animal conservation and management, but methods for measuring the energy expenditure of free‐ranging animals have a variety of limitations. Advancements in biologging technologies have enabled the use of dynamic body acceleration derived from accelerometers as a proxy for energy expenditure. Although dynamic body acceleration has been shown to s
By
Ecosystems Mission Area, Alaska Science Center

Energetic costs of locomotion in bears: is plantigrade locomotion energetically economical?

Ursids are the largest mammals to retain a plantigrade posture. This primitive posture has been proposed to result in reduced locomotor speed and economy relative to digitigrade and unguligrade species, particularly at high speeds. Previous energetics research on polar bears (Ursus maritimus) found locomotor costs were more than double predictions for similarly sized quadrupedal mammals, which cou
By
Ecosystems Mission Area, Alaska Science Center

Convergence of marine megafauna movement patterns in coastal and open oceans

The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals’ movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic f
By
Ecosystems Mission Area, Alaska Science Center

High-energy, high-fat lifestyle challenges an Arctic apex predator, the polar bear

Regional declines in polar bear (Ursus maritimus) populations have been attributed to changing sea ice conditions, but with limited information on the causative mechanisms. By simultaneously measuring field metabolic rates, daily activity patterns, body condition, and foraging success of polar bears moving on the spring sea ice, we found that high metabolic rates (1.6 times greater than previously
By
Ecosystems Mission Area, Alaska Science Center

Non-USGS Publications**

Pagano, A.M., A.M. Carnahan, C.T. Robbins, M.A. Owen, T. Batson, N. Wagner, A.
Cutting, N. Nicassio-Hiskey, A. Hash, and T.M. Williams. 2018. Energetic costs of
locomotion in bears: Is plantigrade locomotion energetically economical? Journal of
Experimental Biology vol. 221 no. 12 p.1-9. doi: 10.1242/jeb.175372
Pagano, A.M., G.M. Durner, K.D. Rode, T.C. Atwood, S.N. Atkinson, E. Peacock, D.P.
Costa, M.A. Owen, and T.M. Williams. 2018. High-energy, high-fat lifestyle challenges an
Arctic apex predator, the polar bear. Science vol. 359 no. 6375 p. 568-572. doi: 10.1126/science.aan8677
Pagano, A. M., Rode, K. D., Cutting, A., Owen, M. A., Jensen, S., Ware, J. V., Robbins, C. M., Durner, G. M., Atwood, T. C., Obbard, M. E., Middel, K. R., Thiemann, G. W., and Williams, T. M., 2017, Using tri-axial accelerometers to identify wild polar bear behaviors: Endangered Species Research vol. 32 p. 19-33. doi: 10.3354/esr00779
Ware, J. V., Rode, K. D., Bromaghin, J. F., Douglas, D. C. Wilson, R. R., Regehr, E. V., Amstrup, S. C., Durner, G. M., Pagano, A. M., Olson, J. W., Robbins, C. T. and Jansen, H. T., 2017, Habitat degradation affects the summer activity of polar bears: Oecologia vol. 184 no. 1 p. 87-89. doi: 10.1007/s00442-017-3839-y
Wiig, Ø., Born, E. W., Laidre, K. L., Dietz, R., Jensen, M. V., Durner, G. M., Pagano, A. M., Regehr, E. V., St. Martin, M., Atkinson, S. N., and Dyck, M., 2017, Performance and retention of lightweight satellite radio tags applied to the ears of polar bears (Ursus maritimus): Animal Biotelemetry vol. 5 no. 9. doi: 10.1186/s40317-017-0124-0
Sequeira, A.M.M., J.P. Rodríguez, V.M. Eguíluz, R. Harcourt, M. Hindell, D.W. Sims, C.M. Duarte, D.P. Costa, J. Fernández-Gracia, L.C. Ferreira, G.C. Hays, M.R. Heupel, M.G. Meekan, A. Aven, F. Bailleul, A.M.M. Baylis, M.L. Berumen, C.D. Braun, J. Burns, M.J. Caley, R. Campbell, R.H. Carmichael, E. Clua, L.D. Einoder, A. Friedlaender, M.E. Goebel, S.D. Goldsworthy, C. Guinet, J. Gunn, D. Hamer, N. Hammerschlag, M. Hammill, L.A. Hückstädt, N.E. Humphries, M.-A. Lea, A. Lowther, A. Mackay, E. McHuron, J. McKenzie, L. McLeay, C.R. McMahon, K. Mengersen, M.M.C. Muelbert, A. M. Pagano, B. Page, N. Queiroz, P.W. Robinson, S.A. Shaffer, M. Shivji, G.B. Skomal, S.R. Thorrold, S. Villegas-Amtmann, M. Weise, R. Wells, B. Wetherbee, A. Wiebkin, B. Wienecke, and M. Thums. 2018. Convergence of marine megafauna movement patterns in coastal and open oceans. Proceedings of the National Academy of Sciences vol. 115 no. 12 p.3072-3077. doi: 10.1073/pnas.1716137115
Pagano, A.M., K.D. Rode, and S.N. Atkinson. 2017. Evaluating methods to assess the body condition of female polar bears. Ursus vol. 28 no. 2 p.171-181. doi: 10.2192/URSU-D-16-00029.1
Pagano, A. M. and Arnold, T. W., 2009, Detection probabilities for ground-based breeding waterfowl surveys: Journal of Wildlife Management vol. 73 no. 3 p. 392-398. doi: 10.2193/2007-411
Pagano, A. M. and Arnold, T. W., 2009, Estimating detection probabilities of waterfowl broods from ground-based surveys: Journal of Wildlife Management vol. 73 no. 5 p. 686-694. doi: 10.2193/2007-524
Arnold, T. W., Pagano, A. M., Devries, J. H., Emery, R. B., Howerter, D. W., and Joynt, B. L., 2008, Social indices of breeding productivity in parkland mallards: Journal of Wildlife Management vol. 72 no. 1 p. 224-230. doi: 10.2193/2007-035

**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.

link

Polar Bears Film Their Own Sea Ice World

In June of 2014, the USGS released the first-ever polar bear point-of-view footage, offering a never-seen-before perspective from the top Arctic...

Read Article
link

Through the Eyes of a Polar Bear

The first "point of view" video from a polar bear on Arctic sea ice has just become available courtesy of the U.S. Geological Survey. 

Read Article
Image: San Diego Zoo Polar Bear
link
Image: San Diego Zoo Polar Bear
link

Science and Products

  • Science
    link
    A polar bear walks across rubble ice in the Alaska portion of the southern Beaufort Sea

    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 sea...
    By
    Species Management Research Program, Alaska Science Center
    link

    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 sea...
    Learn More
    link
    Polar bear still hunting at a seal breathing hole

    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 stressors...
    By
    Species Management Research Program, Alaska Science Center
    link

    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 stressors...
    Learn More
    link
    Polar bear mother and two cubs on the Beaufort Sea ice.

    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 energetics...
    By
    Ecosystems Mission Area, Land Management Research Program, Species Management Research Program, Alaska Science Center
    link

    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 energetics...
    Learn More
  • Data

    Polar Bear Continuous Time-Correlated Random Walk (CTCRW) Location Data Derived from Satellite Location Data, Chukchi and Beaufort Seas, July-November 1985-2017

    his dataset consists of one table with estimated locations of adult female polar bears during July-November 1985-2017, used for quantifying changes in summer land use over time. Locations were estimated with a Continuous Time-Correlated Random Walk (CTCRW) model fit to satellite tracking from radio-collared adult female polar bears. All bears included in this data set were captured and instrumente
    By
    Alaska Science Center

    Polar Bear Continuous Time-Correlated Random Walk (CTCRW) Location Data Derived from Satellite Location Data, Southern Beaufort Sea, 1986-2016

    This dataset consists of one table with predicted locations of adult female polar bears. Locations were derived by a Continuous Time-Correlated Random Walk (CTCRW) model using satellite tracking radio-collared adult female polar bears captured and instrumented in the southern Beaufort Sea, 1986–2016.
    By
    Alaska Science Center

    Serum Urea and Creatinine Levels of Spring-Caught Polar Bears (Ursus maritimus) in the Southern Beaufort and Chukchi Seas

    These data are serum urea nitrogen and creatinine levels for polar bears captured in the southern Beaufort Sea 1983-2016 and the Chukchi Sea 1987-1993 and 2008-2017. The dataset includes relevant information about the bears that were captured including the latitude and longitude of their capture location, capture date, age class and sex, the age and number of cubs accompanying an adult female, and
    By
    Alaska Science Center

    Satellite Location and Tri-axial Accelerometer Data from Adult Female Polar Bears (Ursus maritimus) in the Southern Beaufort Sea, April-October 2014

    These data are from 5 adult female polar bears instrumented in the southern Beaufort Sea, April to October 2014. The dataset is comprised of two data packages: 1) contains GPS and Argos locations collected by satellite-linked GPS receivers mounted on external collars, and 2) contains archival logger data including measures of tri-axial acceleration and conductivity. These data were collected to ga
    By
    Alaska Science Center

    Locations Collected 1985-2015 from Female Polar Bears (Ursus maritimus) with Dependent Young Instrumented in the Southern Beaufort Sea with Satellite-linked Transmitters by the USGS

    This dataset contains a select subset of Argos and GPS locations collected by satellite data collection systems from collared adult female polar bears that were instrumented in the southern Beaufort Sea between 1985-2015. These data were collected to gain insights into movements of southern Beaufort Sea polar bears. These data were collected from adult female polar bears who had dependent young at
    By
    Alaska Science Center

    Bioelectrical Impedance, Deuterium Dilution, Body Mass, and Morphological Measures of Southern Beaufort Sea Female Polar Bears, Spring 2014-2016

    This dataset contains data from the use of bioelectrical impedance analysis and deuterium injection as methods to estimate the body composition of female polar bears in the southern Beaufort Sea subpopulation. Data are provided on bioelectrical impedance resistance measures, the enrichment level of deuterium oxide that was injected and measured in blood samples, and morphological measures.
    By
    Alaska Science Center

    Metabolic Rate, Body Composition, Foraging Success, Behavior, and GPS Locations of Female Polar Bears (Ursus maritimus), Beaufort Sea, Spring, 2014-2016 and Resting Energetics of an Adult Female Polar Bear

    This data release comprises 4 datasets used to measure the field metabolic rate, body composition, foraging success, behavior, and movement patterns of 9 female polar bears on the sea ice of the Beaufort Sea in April, 2014-2016 as well as 1 dataset used to measure the energetic cost of resting in an adult female polar bear at the San Diego Zoo, San Diego, CA. Wild bears were dosed with and had the
    By
    Alaska Science Center

    Measures of oxygen consumption and stroke frequency of a captive subadult polar bear (Ursus maritimus) while resting in water and swimming and diving in a metabolic water flume, Oregon Zoo, 2017

    This dataset contains measures of oxygen consumption and stroke frequency from 1 captive subadult female polar bear (166.5 kg) resting in the water (n = 7 sessions) and swimming and diving in a metabolic swim flume with water circulated at approximately 0.6 km/hr during swimming and diving measurements (n = 6 sessions) in September 2017.
    By
    Alaska Science Center
  • Publications
    Filter Total Items: 22

    Observed and forecasted changes in land use by polar bears in the Beaufort and Chukchi Seas, 1985–2040

    Monitoring changes in the distribution of large carnivores is important for managing human safety and supporting conservation. Throughout much of their range, polar bears (Ursus maritimus) are increasingly using terrestrial habitats in response to Arctic sea ice decline. Their increased presence in coastal areas has implications for bear-human conflict, inter-species interactions, and polar bear h
    By
    Ecosystems Mission Area, Alaska Science Center

    Effects of sea ice decline and summer land use on polar bear home range size in the Beaufort Sea

    Animals responding to habitat loss and fragmentation may increase their home ranges to offset declines in localized resources or they may decrease their home ranges and switch to alternative resources. In many regions of the Arctic, polar bears (Ursus maritimus) exhibit some of the largest home ranges of any quadrupedal mammal. Polar bears are presently experiencing a rapid decline in Arctic sea i
    By
    Ecosystems Mission Area, Alaska Science Center

    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 economic well-being. Thus, mitigating conflict is
    By
    Ecosystems Mission Area, Alaska Science Center

    Polar bear foraging behavior

    Polar bears forage in the marine environment, primarily on the sea ice over the shallow waters of the continental shelf. They are solitary, ambush hunters that catch ringed and bearded seals when they surface to breathe in ice holes or haul out on the ice to rest and molt. In most parts of their range, polar bears experience dramatic seasonal variability in their ability to catch seals, with forag
    By
    Ecosystems Mission Area, Alaska Science Center

    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 validated. Identifying an optimal approach to estimate
    By
    Ecosystems Mission Area, Alaska Science Center, Molecular Ecology Laboratory

    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 and the remaining bears move to land. Although decl
    By
    Ecosystems Mission Area, Alaska Science Center

    Overhauling ocean spatial planning to improve marine megafauna conservation

    Tracking data have led to evidence-based conservation of marine megafauna, but a disconnect remains between the many thousands of individual animals that have been tracked and the use of these data in conservation and management actions. Furthermore, the focus of most conservation efforts is within Exclusive Economic Zones despite the ability of these species to move thousands of kilometres across
    By
    Ecosystems Mission Area, Alaska Science Center

    Energetic costs of aquatic locomotion in a subadult polar bear

    Most marine mammals rely on swimming as their primary form of locomotion. These animals have evolved specialized morphologies, physiologies, and behaviors that have enabled them to efficiently move through an aquatic environment (Williams 1999). Such adaptations include body streamlining, modified plantar surfaces for propulsion, and abilities to remain submerged for extended durations (Williams 1
    By
    Ecosystems Mission Area, Alaska Science Center

    Estimating the energy expenditure of free‐ranging polar bears using tri‐axial accelerometers: A validation with doubly labeled water

    Measures of energy expenditure can be used to inform animal conservation and management, but methods for measuring the energy expenditure of free‐ranging animals have a variety of limitations. Advancements in biologging technologies have enabled the use of dynamic body acceleration derived from accelerometers as a proxy for energy expenditure. Although dynamic body acceleration has been shown to s
    By
    Ecosystems Mission Area, Alaska Science Center

    Energetic costs of locomotion in bears: is plantigrade locomotion energetically economical?

    Ursids are the largest mammals to retain a plantigrade posture. This primitive posture has been proposed to result in reduced locomotor speed and economy relative to digitigrade and unguligrade species, particularly at high speeds. Previous energetics research on polar bears (Ursus maritimus) found locomotor costs were more than double predictions for similarly sized quadrupedal mammals, which cou
    By
    Ecosystems Mission Area, Alaska Science Center

    Convergence of marine megafauna movement patterns in coastal and open oceans

    The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals’ movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic f
    By
    Ecosystems Mission Area, Alaska Science Center

    High-energy, high-fat lifestyle challenges an Arctic apex predator, the polar bear

    Regional declines in polar bear (Ursus maritimus) populations have been attributed to changing sea ice conditions, but with limited information on the causative mechanisms. By simultaneously measuring field metabolic rates, daily activity patterns, body condition, and foraging success of polar bears moving on the spring sea ice, we found that high metabolic rates (1.6 times greater than previously
    By
    Ecosystems Mission Area, Alaska Science Center

    Non-USGS Publications**

    Pagano, A.M., A.M. Carnahan, C.T. Robbins, M.A. Owen, T. Batson, N. Wagner, A.
    Cutting, N. Nicassio-Hiskey, A. Hash, and T.M. Williams. 2018. Energetic costs of
    locomotion in bears: Is plantigrade locomotion energetically economical? Journal of
    Experimental Biology vol. 221 no. 12 p.1-9. doi: 10.1242/jeb.175372
    Pagano, A.M., G.M. Durner, K.D. Rode, T.C. Atwood, S.N. Atkinson, E. Peacock, D.P.
    Costa, M.A. Owen, and T.M. Williams. 2018. High-energy, high-fat lifestyle challenges an
    Arctic apex predator, the polar bear. Science vol. 359 no. 6375 p. 568-572. doi: 10.1126/science.aan8677
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    **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
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    Polar Bears Film Their Own Sea Ice World

    In June of 2014, the USGS released the first-ever polar bear point-of-view footage, offering a never-seen-before perspective from the top Arctic...

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    Through the Eyes of a Polar Bear

    The first "point of view" video from a polar bear on Arctic sea ice has just become available courtesy of the U.S. Geological Survey. 

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  • Multimedia
    Image: San Diego Zoo Polar Bear
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    Image: San Diego Zoo Polar Bear
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