A Mingan Island Cetacean Study (MICS) biologist compares photographs of whales observed in the Gulf of St. Lawrence with those in a whale identification database in August 2016. Scientists are able to identify individual whales by their scars and other unique physical characteristics. Information compiled in photo-identification catalogs over time helps researchers to understand and monitor population demographics, travel patterns, behaviour, social relationships, reproductive success, mortality, health trends and rates of entanglement, for example.