Yesterday on the Piscataqua River, in addition to cavorting seals, I thought it was a Loon beside the boat, then dismissed it, despite the obvious coloring.
That’s a lake bird the Loon, I thought to myself.

I checked this morning and indeed the Loons winter in saltwater.

They have a special gland adaptation that allows them to filter the saltwater and secrete the  salt.

Mike