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Message: <blockquote data-quote="lou salomon" data-source="post: 1404863" data-attributes="member: 16268">4cy michahellis and 4cy cachinnans - nice comparison!in a 2nd winter bird, 3cy now of both sp. primary colour and coverts would be less advanced (underside whitish now, upperside mostly grey) and primaries are 3rd generation - mirror is too large and wrong shape for a 2nd gen. caspian p10 mirror (in this case too longish). also rectrices (tail) still have a black band in 2nd winter, sometimes broken like in the attached 3cy; i got 3 pics of that bird from you, it seemed to have passsed you three times in 6 minutes ..<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /> - often 2nd winter michahellis has a much darker underside than this bird but some are whitish like this. so, a 3rd winter (4cy) - as compared to caspian which ususally has a larger p10 mirror (long) and a small p9 mirror at this age class.</blockquote>