The dorsals and the surfacing style looks like small to midsized Orcas (Killer Whales) to me.. most dolphins are more energetic...
Orcas ARE much larger. Here's one chasing a Dall's Porpoise:
Your image above is two orcas.. likely an adult and a young 'un... no way that 'smaller' one is a Dalls porpoise.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"
Last edited by Faster; 12-26-2011 at 02:07 PM.