I've been a landlord for a long time, and I'm very familiar with the drill every time I show an open unit: will the prospective tenants take it, or not? Same goes for the birdhouses I put up. Carolina wrens have been around my yard for a few weeks, and they've visited this birdhouse inside and out, but... they've yet to make up their minds, I think.
I've had two of these birdhouses up since the previous winter, and they've never been occupied. They're sized for house wrens, but I don't know of anybody in Somerville who has a house wren. I've seen exactly one in all my years here, migrating through, by all appearances. Carolina wren has become much more of a city bird in recent years. I hear them with some frequency, particularly in Cambridge. And because they're here year round, they can get a jump on nesting. and grab the best nesting spots before the house wrens come through.
Unless, of course, they lose out to the chickadees...
