These Franklin's Gulls (Larus pipixcan)
were photographed at Arica, northernmost Chile on December 01,
1993 by Martin Reid:
Note in the first-winter bird (top) that all of the tail plus
the outer 5/6 primaries appear to be fresh 2nd-gen., while the
secondaries and the inner four primaries are worn first-gen. -
thus it has started its first replacement P molt at P5 - more
like Common/Arctic Terns than any gull!; The 2nd-winter bird (bottom)
seems to be missing P1; I'm not sure of the age of the other primaries
- presumably fresh 4th-gen?; the tail looks quite fresh - is it
3rd or 4th-gen (the black spots suggest the former).?:
These two provide a fascinating comparison:- the upper bird seems
to be a first-winter that has already completely replaced its
juv. flight feathers with 2nd-gen feathers: The lower bird I presume
to be in its second winter - it has a worn "first-immature-type"
tail, plus two old outermost secondaries; Ps 1-3 are missing so
I presume Ps 4-10 to be old 3rd-gen feathers; yet the fresh inner
secondaries are still of an immature type - I'd have expected
them to look more adult-like as they should be 4th-gen?:
