Risso’s dolphins are easy to pick out from the state’s other dolphins, often heavily scarred white from squabbles with their own kind and from the squid they hunt, which leaves older animals looking almost ghostly pale. Cape Cod National Seashore anchors most of Massachusetts’ 17 records, sitting near the deeper offshore water this squid-hunting species favors over the shallow bays other dolphins use.
Records cluster in October, more than double any other month, with a smaller July bump. That fall concentration likely tracks squid movements pulling dolphins closer to the Massachusetts coast as summer ends. NatureServe ranks the species S3, vulnerable, in the state, a step below its secure global status.
Full species profile
