Cardigan Bay holds Britain’s largest coastal bottlenose dolphin population. They've been studied since the 1990s but only recently, with the expansion of Sea Watch Foundation’s photo-ID investigations, have we learned that most of the population migrates north for the winter.
A dolphin breaching on its migration path
Individuals are recognised by photographing unique patterns of nicks on their dorsal fins. This low-tech yet relatively non-invasive way of studying migratory marine mammals has revealed that the dolphins from Cardigan Bay migrate at least as far north as the Isle of Man, returning again in spring. This is one of the best examples in Britain of a regular seasonal cetacean movement.
You can report your dolphin sightings here to help the experts track individuals.