A significant, but sometimes neglected, source of data for zoos accredited by the Association of Zoos and Aquariums (AZA) is historical records. While the robusticity of historical records varies substantially, especially as the records get older, there is a wealth of knowledge from past decades just waiting to be collated and assessed. Staff from CZAW have launched a broad multi-institutional study compiling polar bear (Ursus maritimus) growth and rearing records from Species360 and almost 50 AZA-accredited institutions spanning from the 1950s all the way through 2022. Using weights and milestone records from the first year of life, we can track healthy physical development and growth trajectories for these animals. Additionally, we can consider important variables such as sex, whether the cub was mother- or hand-raised, whether the cub was wild-born, cub mortality and age at death, and how cub growth and development in human care has changed over the passing decades. In a time when supporting a stable and sustainable polar bear population is of the utmost importance, having benchmarks by which to monitor newborn polar bears can make all the difference in ensuring that cubs survive, thrive and ultimately join a healthy breeding population.