A group of a dozen or so dolphins are in Rhode Island. The Providence Journal
(registration required) doesn't say what species though.
Update: The Cape Cod Stranding Network sent me this e-mail:
The dolphins that were in the Sakonet River in Rhode Island were Common Dolphins, Latin name: Delphinus delphus. They looked fine, appeared to be feeding, actively swimming. Last we heard, most of the dolphins had moved on and there were only a few left in the river (as of yesterday morning). Thanks for your interest.
Cape Cod Stranding Network Staff