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A locally rare "pelagic" gull species, entering our area as a high altitude migrant, almost always on fall migration.
Juvenile / First Cycle
June
July
August
September
October
November
Very few molting juvenile Sabine's Gulls have been recorded locally - note a few new gray back feathers on the centre left individual.
December
January
February
The gray-backed "first winter" Sabine's Gull plumage is very rare in the Great Lakes or anywhere in North America.
March
April
May
Second Cycle / Basic Adult ?
The change from first to second cycle depends on the timing of the start of the inner primary molt. May/June is used here as an arbitrary cutoff. It is unclear if records of non-hooded "adult-like" Sabine's Gulls in summer and early fall involve second cycle individuals. They may well be full adults with an atypical molt.
June
July
August
September
October
November
Most fall records of Sabine's Gulls involve adults in breeding plumage. As noted earlier, it is unclear if the above bird may involve a second-cycle individual that did not obtain a fully black hood - or if it is simply an adult that had never obtained a black hood, or perhaps has rapidly molted into "winter" plumage (considered least likely due to the worn primaries and lack of primary molt).
December
January
February
March
April
May
Adult
Full adult Sabine's Gulls are shown below. They are notably rarer than juvenile plumaged birds in fall.
June
July
August
September
October
November
It may be expected, illness, or perhaps a biological recognition that their migration is incomplete, that tend to limit molt in Sabine's Gulls locally - with most records of adults having full or mostly black heads and no primary molt even into November.
December
January
February
March
April
May
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