A recent trip to the northern Adriatic Sea coast produced a lot of flight shots of the wintering gulls. I put together overviews of the "winter plumages" of the three most common species.
Altersbestimmung und Kleider der Mittelmeermöwe (Larus michahellis): Erster Winter, Zweiter Winter, Dritter Winter, adult
Ageing and plumages of Yellow-legged Gull (Larus michahellis): first winter, second winter, third winter, adult
Adriatic Sea, February 2019