March 7, 2025

Sofia McGrath

11th Grade

The Young Women's Leadership School of Queens

Introduction

Otherwise known as Ursus maritimus, Polar bears are a species of formidable strength and fortitude that are native to the Arctic. However, these powerful creatures' populations are declining at an unprecedented rate. Polar bear populations are expected to decline by more than 30 percent in the next 35 to 40 years (Kennel). Climate change is the cause of this decline. The implications and complexities of climate change are becoming more evident in the modern day, as it impacts the environment in numerous ways. This issue raises the question of how specifically climate change is resulting in the decline of Polar bear populations. 

Drivers of Population Decline

Scientists have discovered that a major driver of Polar bear populations decline is energy limitation. Climate change is dwindling the surface area of the ice which is causing shorter hunting seasons, thereby resulting in a loss of energy from lack of food amongst Polar bears. This “energy deficit” is a major component that is devastating the population. Climate change immensely alters the Arctic landscape, causing Polar bears to spend more time on land. A postdoctoral researcher at U of T Scarborough explains “A loss of sea ice means bears spend less time hunting seals and more time fasting on land.” Depletion of energy reserves is detrimental to both reproduction and cub survival. When Polar bears fast for long durations of time, they have lesser amounts of stored fats, which impedes their ability to reproduce and raise cubs. The energy depletion also causes polar bears to produce less milk, resulting in underweight cubs, which decreases their likelihood of survival. As the cubs' survival decreases; over time, this results in population decline. 

Bioenergetic Model

The development of a bioenergetic model shows how devastating this “energy deficit”  is on the population decline of this apex predator. Researchers used data collected from polar bears in the western Hudson Bay area- a region of rapid environmental change- to build an individual-based bio-energetic model to hindcast population dynamics(Archer et al.). By tracking the amount of energy polar bears get from hunting seals and the amount of energy they need, this model provides worrisome insights. Based on a study published in Science, the model revealed that the loss of sea ice causing a lack of hunting opportunities drove roughly 50% of the population decline since the 1990s (cited by Kobilinsky). Thus conveying the urgency of this environmental crisis. 

Efforts to Repopulate

Consistent efforts must be made by governments and the people in order to both protect and repopulate the polar bear population. Some notable efforts in the past have fostered a sense of hope for these creatures. For example in  December of 2016, the Polar Bear Conservation Management Plan was published which aimed to conserve and recover the Polar bear population by explaining reasonable courses of action that can be taken and stressing the importance of the mitigation of climate change(Wildlife Management Institute). Individuals should also take measures to help this integral species by actively working to reduce their carbon footprint, and advocating for renewables and climate change policies to contribute to progress. It is the cooperation of individuals, governments, and industries that will create change. 

Conclusion

The polar bear population has undergone a significant decline due to climate change’s effect on the polar bear habitat, causing an energy deficit in the population. While the damage to these formidable creatures is devastating, global and local cooperation is conducive to protecting the current polar bear population and serving to repopulate it in the future.