Cowbird question???

Question

i have a birdhouse which used to have mountain bluebirds in but last time i checked there were two young brownish birds sitting on top of about five eggs. i think that the two brownbirds were cowbirds and too young to be parents so whose eggs would they they be???

Answer 1

These could be baby cowbirds..but they may just be baby bluebirds..they are kind of greyish when they are babies, and will not get their blue coloring for a while.  If they are begging, you can tell by the gape.  Cowbirds have a blood red mouth with a white gape while bluebirds have a yellowish mouth with a yellow gape.

Answer 2

Cowbirds don't sit on their own eggs. They're parasitic nesters -- they lay their eggs in other birds' nests and let the other birds surrogate their babies. They're like cuckoos. So those birds you're seeing aren't cowbirds.

It could be a bluebird -- females are not bright blue.