These Adult Slaty-backed Gulls (Larus
schistisagus) were photographed in Alaska by Tony Leukering:
Gambell, 3rd September (with 2nd-basic Vega Gull); note the almost
complete lack of winter markings:
Nome, 4th September; no winter markings visible; note the odd
molt stage:- P8 missing and P1 half-grown:
Nome 4th September; note the wing molt stage:- P7 and P8 missing/short;
this probable 4th-basic bird has considerable winter streaking
- unlike the adult Vega Gull nearby; :
