How long before bluebirds fledge: Age of nest departure  According to Benedict Pinkowsky (1974c), who monitored 184 nestling eastern bluebirds in Michigan, young bluebirds fledged between days 16 and 22 after hatching. Nestling bluebirds leave the nest on average 19 days after hatching, based on all 184 nestlings in the study.  But there is a […]