You're correct on both counts. You can tell a male common starling in spring as the bill colour changes to almost completely yellow, with a bluish base. Otherwise in both sexes the bill is black.
Starlings attain adulthood in their second year as far as I'm aware, so a bird of this year will become an adult by next year.
Last edited by PYRTLE : Monday 24th September 2018 at 12:30.