Lebby
Member
I live in Michigan and oversee the maintenance of about 100 bluebird nest boxes. You probably have tree swallows nesting in the bluebird boxes, not martins, which nest in a single colony. To get around this, we place nest boxes in pairs as they will nest next to another species, but not their own kind.
Both robins and bluebirds will overwinter if the temperatures are not too cold. They feed on dried berries left in the trees.
We have blue birds over wintering this year located southern WI. Just acouple of days ago when the temp was -18F daytime. They were sitting at our heated bird bath.
Curious as to above qoute as to putting up "pairs" of blue bird houses. Would these be mounted on the same post with openings opposite directions from each other or short distance (i.e. 2-3 ft) from one another or? We have the tree swallow / blue bird dilema. Sparrows will take over a blue bird nest box with no mercy. Double boxes sound as a small price to pay to get rid of the pesky and very smart sparrows.
Have a great day!