Evaluating Maternal Polar Bear Denning Habitat Along the Arctic Coastal Plain and Assessing the Potential for Noise Disturbance in Polar Bear Dens

Polar bears (Ursus Maritimus) in northern Alaska are increasingly choosing land instead of sea ice to build their maternity dens. As sea ice continues to decline due to climate change, this shift makes it more important than ever to identify and protect the areas where polar bears dig dens to give birth and raise their cubs. In the first part of my research, I used new satellite-based elevation data to map potential polar bear denning habitat across a large section of Alaska’s Arctic Coastal Plain. This technology allowed me to identify the types of sloped terrain where drifting snow collects—conditions that polar bears need to create a den. I compared my results to older maps and on-the-ground measurements, and found that this approach provided an effective and efficient way to locate potential denning areas. I also looked at how much oilfield infrastructure overlaps with denning areas to help support future development decisions. In the second part of my research, I studied how industrial noise penetrates into polar bear dens. I built artificial dens in mapped polar bear habitat and placed sound recording equipment inside and outside each den. I recorded more than 1,200 vehicles passing on nearby roads and found that snow can block much of the noise—but not all of it. How much sound penetrates a den depends on factors like snow depth and wind speed. Some dens were better at blocking noise than others. This means that some polar bears may be more at risk of hearing disturbance from oilfield traffic, especially when they are raising vulnerable newborn cubs inside the den. Together, my work provides new tools and information to help wildlife managers and industry partners better protect polar bears during this critical part of their life cycle.