Photo-identification

Photo-identification is a non-invasive technique that allows us to identify individual whales and dolphins based on natural markings such as pigmentation patterns, scarring, and dorsal fin shape. By building long-term photo-identification catalogs, we can track individuals across seasons and years to estimate population size, survival, residency patterns, reproductive rates, and site fidelity. This approach allows us to examine health, behavior, and habitat use at the level of individual animals while also generating population-level estimates of abundance, movement, and demographic trends. Because cetaceans have unique markings – much like fingerprints – photo-identification provides a powerful way to monitor populations without physically handling animals.

Traditionally, photo-identification images have been matched to catalogs manually, an accurate but time-intensive process. In recent years, advances in machine learning and artificial intelligence have transformed this process. Automated image-recognition algorithms can now assist with matching individuals based on pigmentation patterns, fin shape, and scarring, dramatically increasing efficiency while maintaining accuracy. These tools allow us to process large datasets more rapidly, expand collaborative catalog matching across regions, and strengthen long-term monitoring efforts. Learn more about these recent advances in our publications (Patton et al., 2023 & Patton et al., 2025) and through programs such as Happywhale.)