Chestnut Backed Chickadee

I have seen the evicted Chestnut Backed Chickadee a few times since the Violet Green Swallows took over their nest and young. The chickadee has flown in near his former nesting site, fed at the feeder and quickly flew away. I am not certain what happened to the baby chickadees. This article cites Chestnut Backed Chickadee nests have been raided or predated by squirrels, House Sparrows, House Wrens, and Bewick's Wrens (observed). The nest box itself was built to exclude predators of Violet Green Swallows NOT predators of Chestnut Backed Chickadees. I suppose then that Violet Green Swallows are higher on the food chain than Chickadees. Smaller chickadee nests have the least chance of survival. I heard only 3 or 4 young in the Chickadee nest.

This site seems to have a little information on predators.

"# Chickadee: pretty much everybody kicks them out, including bumblebees, although occasionally they win against bluebirds. Mountain Chickadees may lose out to House Wrens and Violet-green Swallows. Eastern bluebirds have been known to remove chickadee nestlings from a box. (BNA). Other birds will lay their own eggs on top of or alongside chickadee eggs (see photo above.) Note: A 1 1/8" hole restrictor can be placed on a box that has at least one chickadee egg in it to protect their nest from being overtaken by larger competitors. If their nest is taken over, try moving it to a paired box (5-20 feet away) with the entrance hole facing the opposite direction (but away from prevailing winds.) Will not returned to a failed nest site to try again."

There is also a page on Violet Green Swallows.

One day the chickadees were feeding their young and the next day a couple of Violet Green Swallows were flying in nesting material. Did not see the chickadees leaving the nest nor did I see the Violet Green Swallows removing the old chickadee nest.