@islambad Well . . . since you asked . . . I've checked online several times to find out if it's 'titmouses' or 'titmice' . . . this is what most of the references have to say (I've copied/pasted this from an online inquiry):
The word titmouse doesn’t have any connection to the rodent. Instead, the second syllable is based on the Old English word mase, which means “small bird.” Technically, there’s no reason why mouse and mice should match titmouse and titmice. A purist would probably say titmouses is correct. On the other hand, a couple of major dictionaries (and bird guides) give titmice as plural. So you can probably get away with either!
The word titmouse doesn’t have any connection to the rodent. Instead, the second syllable is based on the Old English word mase, which means “small bird.” Technically, there’s no reason why mouse and mice should match titmouse and titmice. A purist would probably say titmouses is correct. On the other hand, a couple of major dictionaries (and bird guides) give titmice as plural. So you can probably get away with either!