A solitary polar bear swimming in an ice-free Arctic has become a symbol of the impact of a warming planet on wildlife. However, in the Barents Sea region north of Norway, the polar bears are faring relatively well at present.
Contrary to expectations, a recent study published in Scientific Reports reveals that the long-term decline in sea ice and the increasing number of ice-free days have not significantly harmed this particular subpopulation of polar bears. Andrew Derocher, a professor of biological sciences at the University of Alberta and co-author of the study, notes that the bears in this region are managing to adapt to the changing environment and maintain their health.
Experts emphasize the need to consider the variability within polar bear populations when assessing the impacts of climate change. While some animals may benefit from shifting environmental conditions, such as the Barents Sea bears, the overall outlook remains concerning. The researchers warn that despite the current resilience shown by these bears, ongoing loss of sea ice poses a severe threat to their long-term survival.
The study, based on data collected from live captures of polar bears in the Svalbard archipelago between 1995 and 2019, involved 770 bears and provided valuable insights into their body condition and overall health. The researchers conducted capture-mark-and-recapture expeditions, which involved using helicopters to track and sedate the bears for measurement and assessment.
The study highlighted the profound effects of a warming Arctic on the polar bear population in the region. Despite facing challenges such as earlier sea ice breakup and longer ice-free periods, the bears in the Svalbard area have managed to stabilize their body conditions after an initial decline.
One possible explanation for the bears’ resilience is their consumption of alternative prey not typically part of their diet, such as walruses, bird eggs, and whale carcasses. These additional food sources, made more available due to population rebounds and changing ecosystems, may be contributing to the bears’ ability to sustain themselves without relying solely on traditional prey like ringed seals and bearded seals.
While the success of the Barents Sea bears offers a glimmer of hope, experts caution that not all polar bear populations are faring as well. In regions like western Hudson Bay and the Beaufort Sea, polar bears continue to face declining body conditions, reduced survival rates, and challenges to reproduction due to diminishing sea ice.
As climate change accelerates, the fate of polar bears remains uncertain. While short-term adaptations may provide some reprieve for certain populations, the long-term prognosis is ominous as the loss of sea ice threatens the very existence of these iconic Arctic animals. The future of the Barents Sea bears, like that of all polar bears, hangs in the balance as the world grapples with the consequences of human-induced climate change.