A question as polarizing as the subjects themselves: are polar bear numbers on the decline?
Once recognized as Coco Cola’s charismatic Christmas mascot, these bears have become the poster child for climate change. However, there is fierce opposition and claims arguing that numbers are increasing, and that climate change is not to blame. So, which one is it?
The confusion, is in part due to the different subpopulations of the bears found throughout the artic and their historically elusive nature. There are a total of 19 recognized subpopulations, all inhabiting different habitats within the artic region. Not much was known about any of the population sizes in the 50’s and 60’s, making it difficult to draw real comparisons. This makes it easy to focus on a currently thriving population, whose numbers are stable or increasing, while neglecting populations whose numbers are on the decline. Such was the case made by Canadian scientist Mitch Taylor, a polar bear expert.
In 2005 Taylor claimed that the number of bears was on the rise, denying any impact from climate change and focusing on hunting instead. While this might have been a partial truth for the Canadian population of bears, Taylor failed to mention any of the other subpopulations. When you track changes across the total population, the numbers reveal something else entirely. According to a 2009 report by the IUCN Polar Bear Specialist Group, of the 19 populations, a total of 8 are in decline, and the World Wildlife Fund (WWF) estimates that there has been a 40% loss since 2001 – 2010 alone. The fact is that this majestic creature is still considered vulnerable on WWF’s endangered species list. This is in part due to the rapidly changing climate of the artic and the potential for even more drastic changes in the near future.
In the Artic, the increase in temperature as result of climate change has caused a loss of sea ice, an essential element to the survival of these bears. Classified as marine mammals, polar bears use sea ice to aid in the hunt Artic seals. Without sea ice, there are fewer seals to hunt and longer distances to swim. In the summer months, the rapidly melting sea ice means that there less time to hunt and build fat, and harsher hunting conditions. Among the Hudson Bay subpopulation, where the impact of climate change on habitat is most noticeable, the average weight of female polar bears has dropped by about 21% between1980 and 2004. Having to work harder, travel further and compete more for less food means higher risk of starvation and increased mortality rates.
With the effects of climate change predicted to continue and worsen, habitat loss is expected to increase. If these bears are landlocked due to loss of sea ice, their lives and the lives of neighboring humans will remain at risk. We must take action and demand change; otherwise Polar bears, like many species before them, may become creatures of the past.
Climate Science Glossary https://www.skepticalscience.com/polar-bears-global-warming.htm Accessed September 10, 2018
Polar Bear Population Decline a Wake Up Call For Climate Change Action https://www.worldwildlife.org/stories/polar-bear-population-decline-a-wake-up-call-for-climate-change-action Accessed September 10, 2018
WWF. Species List: https://www.worldwildlife.org/species/directory?sort=extinction_status&direction=asc Accessed September 10, 2018
WWF. Polar Bears: https://www.worldwildlife.org/species/polar-bear Accessed September 10, 2018