Willet,
western subspecies, Tringa
semipalmata inornata
The western subspecies, "inornata," migrates through the Bay Area and also winters here. It is on average larger, with proportionately longer
and slimmer bill, paler, more likely to appear gray rather than brown, and less heavily speckled in its breeding plumage, shown above, than
the eastern subspecies, "semipalmata," which is shown here. These may be recognized as separate species some day.
The flying bird above is on its nesting ground in the marshes of Sierra Valley, on the east side of the Sierras north of Lake Tahoe.
The Willet shown above and below in late July has recently returned to San Francisco
Bay from the nesting grounds, still mostly in breeding plumage, with a few solid-gray
non-breeding feathers molted in.
Above, another Willet in July, this one showing more new solid-gray feathers in back replacing dark brown breeding feathers, while the latter
are still retained in the bird's front.
Molt runs the other way in spring; the Willet above has mostly molted its head and underparts to the striped and spotted breeding plumage,
while many worn solid-gray are still retained on the back and wings.
Willets in non-breeding plumage are plain gray birds, drab and downright inconspicuous--unless ...
... they forage fiercely, or...
...prance in the surf, or...
...fly by themselves, above and below, or...
... fly in a flock, above (note single Marbled Gotwit) and below, or...
... fight. This may look like some kind of rough courting action of the kind familiar
among ducks, but in fact it is a territorial spat. Birds of North America Online
reports that Willets fight over territory even on the wintering ground, and that in
fights they sometimes pull out opponents' tail feathers.
And plain as a Willet can be when it just stands there, it can still catch the eye in the warm light of the setting sun.
Finally, an oddity. This Willet has gone through the pre-basic molt in late summer that normally produces
the typical plain non-breeding plumage. But in this case, the bird grew in a second round of the striped
head and underparts plumage that is normal in the breeding season. If this were breeding plumage
retained from the previous spring and summer by a failure or long delay in pre-basic molt, it would
be severely worn, but these feathers appear quite fresh. This is thus basic or non-breeding plumage
with feathers that resemble those of alternate or breeding plumage.