Most ducks (most birds too) undergo a plumage change, or molt, twice per year alternating between a breeding and a non-breeding phase. Long-tailed ducks are different. Each full molt is interrupted by a partial molt thus giving the long-tail four plumages per year.
A Pigeon Guillemot (Cepphus columba) in it's non-breeding plumage. Pigeon guillemots dive to 150 feet to forage for mollusks, crustaceans and small fish. Unlike other Alcids (murres, murrelets, puffins, auklets etc) who use their wings to swim underwater, pigeon guillemots also use their feet.
In open water, alcids fly in flocks close to the surface in search of places where prey fish are concentrated up to 100 times their average densities. Closer to shore, they use areas where prey is concentrated by strong currents flowing over shoals and banks and in passes between islands (!). They are able to locate oceanic "fronts" where water masses of different densities and temperatures collide forming underwater "walls" against which prey get trapped.
Tufted Puffin (last seen in October)
The White-winged Scoter (Melanitta fusca) is the largest of all scoters. It dives for clams and other shellfish
Long-tails, a female here, spend their winters at sea over sandy substrates (most of the West Coast population winters in the Bering Sea) They eat mostly mollusks and crustaceans and do most of their foraging within 30 feet of the water surface.
A Pelagic Cormorant (Phalacrocorax pelagicus). Cormorants mostly eat small fish, the pelagic species forages around submerged rocks.
Pretty no? Smelly too. This work began to appear in November as the cormorants took up positions on the cliff to our south.
Larger flocks have been flying overhead during the past three or so weeks. We don't know what kind of birds these are but we have seen King Eiders moving south and yesterday saw Steller's Eiders eating with the White-winged Scoters, three pair of Red-breasted Mergansers, a female bufflehead, and a Crested Auklet: our new neighbors for the winter.
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