Over the month of May, observers on the north eastern coast of England were regularly treated to groups of bottlenose dolphins. Until recently this species of dolphin was relatively uncommon to this area and its most southerly point on the east coast seemed to be Northumberland. However, the past months have illustrated that these dolphins are travelling as far south as Whitby and Flamborough Head in North Yorkshire as reported by Sea Watch Coordinator Robin Petch. By encouraging people to take photos of the dorsal fin that can used for photo identification we have now found a match and can reveal that a dolphin seen at Whitby is part of the Moray Firth population in north east Scotland, almost 300 miles from Whitby. This dolphin has also been recorded in St. Andrews Bay, Fife and north Tyneside. It is unclear as to why these animals are travelling so far south from their regular habitat.
It was previously thought that the two UK resident populations of bottlenose dolphins were closed, meaning that there was little mixing outside these populations. These populations exist in the Moray Firth and in Cardigan Bay, Wales. Evidence from photo identification now shows that dolphins belonging to the Moray Firth population are travelling more than 800 miles, being seen off Galway and Cork in Ireland. The Cardigan Bay dolphins have also been identified in Anglesey and northwest England off Liverpool Bay.
These discoveries provide significant information on the movements of bottlenose dolphins. Little is still known about long range movements of the species and the mixing of bottlenose dolphin communities but it now seems clear that these resident populations are open, regularly travelling to other waters and being associated with other dolphins. Further monitoring using photo identification is required to build a clearer picture of bottlenose dolphin movements, group association and habitat use.