Polar Bears and Climate Change: The Science Speaks for Itself

In the past month, there have been three major stories concerning polar bears:

  1. On July 18, wildlife researcher Dr. Charles Monnett was put on suspension by his employer, the U.S. Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE), pending an Inspector General’s investigation into undisclosed “integrity issues.”
  2. On July 19, USGS polar bear scientists at an international bear conference reported their early findings that the increasingly long distances that polar bears have to swim to reach polar ice in the Beaufort and Chukchi Seas puts adults and their cubs at increasing risk of drowning. This provided additional support for previous published reports by George M. Durner and by Charles Monnett and Jeffrey Gleason of drowned polar bears.
  3. On August 4, the same agency that suspended Dr. Monnett, BOEMRE, tentatively approved plans by Shell Oil to begin drilling for oil in the Beaufort Sea off Alaska’s coast as early as next year.

Of these three stories, the one that has received the most attention is the first. Politicians and interest groups that deny climate change is happening leaped on the Monnett suspension story. They are misleading the public by falsely discrediting scientific findings about the impacts of climate change on polar bears, even though BOEMRE has subsequently clarified that the suspension was not based on any concerns over Monnett’s published science, but rather on some-yet-to-be identified concerns over whether appropriate administrative processes were followed.

Read “Why Big Oil is Declaring War on Polar Bears – And How You Can Help Fight Back” to learn why the Monnett investigation has been seized upon by big polluters as a way to confuse the public about climate science.

Sadly, it is the other two stories that should be getting attention and causing alarm.

8 Science-Backed Facts About Polar Bears and Climate Change

The scientific evidence that polar bears are at increasing risk from climate change is overwhelming.  National Wildlife Federation has put together a helpful reference list of scientific studies, reports and books on the topic. This compilation is not intended to provide an exhaustive list of the science, but rather an overview of the newest and best science. To facilitate access, we have listed the top scientific findings, and included citation(s) for the original study.

Arctic sea ice is declining as a result of climate change.

References: 23, 9, 13, 18, 5, 25, 2, 3, 17

Sea ice is declining much faster than projected even under the worse case scenarios.

Reference: 17

Thicker, more stable multi-year sea ice is being replaced by thinner annual sea ice, reducing the ability of polar bears to capture their primary food, seals.

References:14, 17, 26, 13, 21, 7, 18, 6, 28

Polar bears are swimming further distances to reach the sea ice on which they hunt, increasing risks to both adult and subadult polar bears.

References: 6, 17, 20, 7, 14, 16, 13, 18, 10, 11

Sea ice decline means fewer hunting opportunities for polar bears and increased scarcity of food.

References: 17, 20, 14, 21, 16, 23, 19, 26, 24, 13, 6, 7, 18, 5, 1,11

Polar bear populations are already significantly decreasing in the southern portions of their range because of reduced hunting opportunity. Similar changes are beginning to be seen in more northern areas.

References: 17, 14, 20, 21, 16, 12, 23, 19, 26, 24, 13, 7, 18, 5, 27

Climate change will also increase conflicts between humans and bears.

References: 17, 18, 29

Polar bears can still be saved if greenhouse gas emissions are reduced.

References: 9, 8

Take Action

Stop a New Attack Threatening Polar Bears!

Members of Congress are considering legislation that cripples long-standing conservation programs,  increases global warming pollution, and facilitates further drilling in Alaska that threatens the very survival of polar bears. Help protect polar bears and many more wildlife by sending a message to your members of Congress, urging them to stop this unprecedented attack on wildlife.



1. A Bayesian Network Modeling Approach to Forecasting the 21st Century Worldwide Status of Polar Bears
2. A rapidly declining perennial sea ice cover in the Arctic
3. Accelerated decline in the Arctic sea ice cover
4. Arctic sea ice decline: Faster than forecast
5. Climate change threatens polar bear populations: a stochastic demographic analysis
6. 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
7. Effects of Earlier Sea Ice Breakup on Survival and Population Size of Polar Bears in Western Hudson Bay
8. Forecasting the Range-wide Status of Polar Bears at Selected Times in the 21st Century
9. Greenhouse gas mitigation can reduce sea-ice loss and increase polar bear persistence
10. Observations of mortality associated with extended open-water swimming by polar bears in the Alaskan Beaufort Sea
11. Polar Bear Distribution and Habitat Association Reflect Long-term Changes in Fall Sea Ice Conditions in the Alaskan Beaufort Sea
12. Polar Bear Population Status in Southern Hudson Bay, Canada
13. Polar Bears in a Warming Climate
14. Polar Bears in the Southern Beaufort Sea I: Survival and Breeding in Relation to Sea Ice Conditions, 2001-2006
15. Polar Bears in the Southern Beaufort Sea II: Demography and Population Growth in Relation to Sea Ice Conditions
16. 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
17. Polar Bears: The Natural History of a Threatened Species
18. Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic
19. Possible Impacts of Climatic Warming on Polar Bears
20. Predicting Movements of Female Polar Bears between Summer Sea Ice Foraging Habitats and Terrestrial Denning Habitats of Alaska in the 21st Century: Proposed Methodology and Pilot Assessment
21. Predicting survival, reproduction and abundance of polar bears under climate change
22. Predicting the Future Distribution of Polar Bear Habitat in the Polar Basin from Resource Selection Functions Applied to 21st Century General Circulation Model Projections of Sea Ice
23. Range-Wide Status Review of the Polar Bear
24. Recent observations of intraspecific predation and cannibalism among polar bears in the southern Beaufort Sea
25. Sensitivity of Hudson Bay Sea ice and ocean climate to atmospheric temperature forcing
26. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice
27. Temporal Trends in the Body Condition of Southern Hudson Bay Polar Bears
28. Trends in the Dates of Ice Freeze-up and Breakup over Hudson Bay, Canada
29. 3rd International Bear-People Conflicts Workshop Summary