Consequences of long-distance swimming and travel over deep-water pack ice for a female polar bear during a year of extreme sea ice retreat

  title={Consequences of long-distance swimming and travel over deep-water pack ice for a female polar bear during a year of extreme sea ice retreat},
  author={George M. Durner and John P. Whiteman and Henry J. Harlow and Steven C. Amstrup and Eric V. Regehr and Merav Ben‐David},
  journal={Polar Biology},
Polar bears (Ursus maritimus) prefer to live on Arctic sea ice but may swim between ice floes or between sea ice and land. Although anecdotal observations suggest that polar bears are capable of swimming long distances, no data have been available to describe in detail long distance swimming events or the physiological and reproductive consequences of such behavior. Between an initial capture in late August and a recapture in late October 2008, a radio-collared adult female polar bear in the… 
Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water
It is shown that adult female polar bears and their cubs are capable of swimming long distances during periods when extensive areas of open water are present, however, long-distance swimming appears to have higher energetic demands than moving over sea ice.
Space-use strategy affects energy requirements in Barents Sea polar bears
Polar bears Ursus maritimus are currently facing rapid environmental changes with loss of sea ice and shifts in their prey distribution. Two distinct ecotypes exist in the Barents Sea, where sea ice
Aquatic behaviour of polar bears (Ursus maritimus) in an increasingly ice-free Arctic
The considerable swimming and diving capacities of polar bears might provide them with tools to exploit aquatic environments previously not utilized, likely to be increasingly important to the species’ survival in an Arctic with little or no persistent sea ice.
Changes in winter and spring resource selection by polar bears Ursus maritimus in Baffin Bay over two decades of sea-ice loss
It is indicated that significant changes in available sea-ice habitat and habitat use in Baffin Bay have occurred since the mid-1990s and this subpopulation will likely experience negative population-level impacts related to a changing climate in the coming decades.
Increased Arctic sea ice drift alters adult female polar bear movements and energetics
Polar bears selected similar habitats in both periods, indicating that faster drift did not alter habitat preferences, and changes in ice drift, and associated activity increases, likely exacerbate the physiological stress experienced by polar bears in a warming Arctic.
Migratory response of polar bears to sea ice loss: to swim or not to swim
Results corroborate the hypothesis that long‐distance swimming by polar bears is likely to occur more frequently as sea ice conditions change due to climate warming, but also suggest that the magnitude of the effect likely varies within and between populations.
Sea ice resource selection models for polar bears in the Barents Sea subpopulation
The extent, thickness and age of Arctic sea ice has dramatically declined since the late 1990s, and these trends are predicted to continue. Exploring the habitat use of sea-ice-dependent species can
Physiological consequences of Arctic sea ice loss on large marine carnivores: unique responses by polar bears and narwhals
Assessment of how sea ice loss may differentially affect polar bears that hunt on the ice surface and narwhals that hunt at extreme depths below found that major ice loss translated into elevated locomotor costs that range from 3- to 4-fold greater than expected for both species.
Polar bears and sea ice habitat change
The polar bear (Ursus maritimus) is an obligate apex predator of Arctic sea ice and as such can be affected by climate warming-induced changes in the extent and composition of pack ice and its
Importance of fast ice and glacier fronts for female polar bears and their cubs during spring in Svalbard, Norway
Arctic sea ice is declining rapidly, making it vital to understand the importance of dif- ferent types of sea ice for ice-dependent species such as polar bears Ursus maritimus. In this study we used


Observations of mortality associated with extended open-water swimming by polar bears in the Alaskan Beaufort Sea
It is speculated that mortalities due to offshore swimming during late-ice (or mild ice) years may be an important and unaccounted source of natural mortality given energetic demands placed on individual bears engaged in long-distance swimming.
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
The results suggest that long-term reductions in sea-ice could result in an increasing proportion of the Southern Beaufort Sea polar bear population coming on land during the fall open-water period and an increase in the amount of time individual bears spend on land.
Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice.
The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines.
Reduced body size and cub recruitment in polar bears associated with sea ice decline.
  • K. Rode, S. Amstrup, E. Regehr
  • Environmental Science
    Ecological applications : a publication of the Ecological Society of America
  • 2010
It is suggested that declining sea ice is associated with nutritional limitations that reduced body size and reproduction in this population of polar bears and reduced reproductive output and juvenile survival.
Locomotion in the North American mink, a semi-aquatic mammal. I. Swimming energetics and body drag.
  • T. Williams
  • Environmental Science
    The Journal of experimental biology
  • 1983
Oxygen consumption during surface swimming and total body drag were investigated in the North American mink, Mustela vision Schreber, and a streamlined body shape, characteristic of many mustelids, aided in reducing drag at high speeds.
Energetics of locomotion by the Australian water rat (Hydromys chrysogaster): a comparison of swimming and running in a semi-aquatic mammal.
The energetic costs of locomoting either in water or on land were high for the semi-aquatic Hydromys chrysogaster, however, the relative costs were lower than when an aquatic specialist attempts to move on land or a terrestrial specialist tries to swim.
Recent observations of intraspecific predation and cannibalism among polar bears in the southern Beaufort Sea
It is hypothesize that nutritional stresses related to the longer ice-free seasons that have occurred in the Beaufort Sea in recent years may have led to the cannibalism incidents observed in 2004.
Predicting 21st‐century polar bear habitat distribution from global climate models
Projections of polar bear (Ursus maritimus) sea ice habitat distribution in the polar basin during the 21st century were developed to understand the consequences of anticipated sea ice reductions on
Temporal variation in reproduction and body mass of polar bears in western Hudson Bay
We studied annual and long-term variation in rates of reproduction in female polar bears (Ursus maritimus) in western Hudson Bay from 1966 to 1992. In addition, long-term trends in body mass were
Transitions from Drag-based to Lift-based Propulsion in Mammalian Swimming
  • F. Fish
  • Environmental Science, Biology
  • 1996
Examination of modern analogs to transitional swimming stages suggests that only slight modification to the neuromotor pattern used for terrestrial locomotion is required to allow for a change to lift-based propulsion.