Mark,
I think most of the bait in Maine is similar to what you'd find further
south. I live in Kport, and in our area it's primarily sand eels, bunker,
mackerel, silversides and eels. Did good with a squid pattern last year
too, but I usually use clousers, surf candy clones or humongous bunker
flies, the latter particularly productive in fall. Bait probably shows up
a week or two after Plum Island gets it. Oh, there's the worm hatch too,
they can get selective during that one.