Billie,
Let's just hope that your martins are arriving late. When you say
you had a problem with a raccoon I'm assuming you must not have had
a predator guard on your pole. Did any of the young birds fledge?
Normally if the adult birds are successful in raising young and they make
it through the migration they will return I guess that is unless they had a real bad experience with a predator such as a snake or owl or hawk, or as in your case a raccoon.

Don't give up on them though as they
could show up anytime an the Sy birds are just now starting to head this
way from the south. My colony is just now starting to pick up in size. Last
year I had 70 pair and as of today I only have around 25 pair so we have
a quite a ways to go yet.Unless the hurricanes did have some kind of effect on them last year. I guess we will just have to wait and see what the
outcome is this year.
I wish you all the luck I can!!!