Winter distribution of Bottle-nosed Dolphins (Tursiops truncatus (Montagu)) in the inner Shannon Estuary

In order to record the distribution of Bottle-nosed Dolphins Tursiops truncatus (Montagu 1821) in the inner part of the Shannon Estuary, dedicated boat transects were carried out during the winter (November to March). Bottle-nosed Dolphins were recorded on seven of the ten transects with six of these sightings between Scattery Island and the Tarbert Races and with only one up-river, off Foynes Island. Eighteen individual dolphins were recognized using photo-identification all of which had been previously recorded in the estuary. The results confirm that Bottle-nosed Dolphins do occur regularly in the Shannon Estuary during winter months, with sighting frequency comparable to transects carried out during the summer in other parts of the estuary