I don’t know if it’s an official rookery but I see them all the time on the Barrington/Riverside line. There’s a parking spot for birdwatching on 114 in Barrington where you could park to see them. It’s 5 minutes from the EP/Seekonk Home Depot spot another poster mentioned. There’s actually two birdwatching spots right there, one in Barrington and another a little closer to the radio station