Although they are more insect specialists--just look at those long thin bills, perfect for prying into nooks and crannies in search of nibbles--wrens (Carolinas at least, like these) will eat other stuff if the opportunity arises. For instance, when you've put out high-fat and -protein packs like peanuts... The wrens have to work a bit, using that bill as a hatchet to break the nuts into smaller pieces, but apparently it's well worth the effort: They are at my peanut feeders almost as much as the birds better equipped to deal with such food. (Chickadees, titmice, nuthatches and woodpeckers, with their bills designed for cracking, crushing and grinding.)
