All five of the bluebird nesting boxes we placed in early spring in collaboration with the Bronx River Sound Shore Audubon Society are fully occupied… but not with bluebirds! Iridescent blue-green tree swallows have moved into each bird box and created beautiful feathered nests that are now filled with newly hatched babies.
Tree swallows and bluebirds compete for the same nesting sites. Normally tree swallows have just one brood per year, while bluebirds will have two. Once the tree swallows leave the nest, bluebirds will have the opportunity to move in. Trained volunteers will continue to monitor the boxes throughout the season.
Tiny, pink, newly hatched tree swallow babies.
Older tree swallow babies with grey plumage.
A bird nesting box with nesting material poking through.
Photo credit: Anik McGrory