What a female polar bear (Ursus maritimus) does between entering her den and emerging months later with or without cubs has been impossible to observe in the wild. In zoos, however, we can equip maternal denning spaces with cameras to capture activity and sound throughout a female’s denning period. These cameras allow us continuous visual access to female bears without disturbing them during this important and precarious season. We can track activity, with particular attention to when females begin decreasing food consumption and increasing sleep – behaviors that signal her readiness to transition into her den for a restful winter. As of now, we have no way of testing whether a female bear entering her den is pregnant or not. As a female enters her den, care teams prepare for cubs who may or may not arrive. Monitoring a female in her den can often be the only way of determining when a female goes into labor, the health status of any cubs she births and what support she or her growing family may need. With long-term den monitoring, we can establish what a non-pregnant denning season looks like and compare it against the behavioral trends or shifts unique to a bear who may be preparing to birth and rear cubs. These types of behavioral indicators are critical for ensuring that everyone — from the veterinarians to the animal care team — is ready to support the bears and ensure a healthy, thriving bear population.