Hells
Your will see Dolphins off the Dorset coast sometime, Dolphins especially are spotted regularly of Poole and Swanage, in fact I believe there is a resident pod along our part of the coast. According to the Durlston Marine watch oct/nov/dec are the best times to see Dolphins, however I have only seen them in the summer months
Last time I saw them was the week before we went to Alderney they were off of Durlston swimming towards Swanage Bay
Martin