An individual's age is a critical parameter for understanding population structure and informing management actions, but the traditional methods for aging cetaceans require tissues obtained invasively or from dead individuals. DNA methylation, the addition of methyl groups in the genome, has been demonstrated to correlate with age in organisms ranging from fishes to humans and presents a promising alternative for estimating age. The CCGL are partners in developing models based on DNA methylation data for endangered cetaceans, including the Cook Inlet, Alaska Distinct Population Segment of beluga whales and Maui dolphins in New Zealand.