On Cooper Road in Milton there is a sizeable flock (~80) of Brown-headed
Cowbirds. I am sure that they are taking advantage of the near by farmyard
so there presence does not surprise me. However, there level of singing
makes me wonder: because of their parasitic ways do Brown-headed Cowbirds
begin to sing and initiate courtship in response to singing and courtship from
potential hosts (i.e.- Northern Cardinal)?