SURF SCOTER
Melanitta perspicillata
The only scoter confined as a breeding species to America,
Surf Scoters are among the least studied of northern waterfowl.
Named for their propensity to forage in ocean surf and breaking waves,
the specific name perspicillata is from the Latin
for conspicuous or spectacular,
in reference to the bizarre, multicolored drake bill.
The decidedly odd-shaped bill has earned them a multitude of
descriptive monikers, including Goggle-nose, Horse-head Coot,
Plaster-bill, Snuff-taker, Blossom-billed Coot,
Bottle-nosed Diver and Mussel Bill.
Their massive, gibbous bill is strangely swollen on the sides,
and the pronounced hump on top gives Surf Scoters a distinct
"Roman nose" appearance.
The drake bill is adorned with an elaborate pattern of
reddish-orange, yellow, black and white, as well as prominent,
square, black basal patches.
The velvety-black males are noted for a conspicuous
white forehead patch that varies greatly in size and shape,
as well as elongate, hairlike white feathers that form a short,
mane-like, triangular nape patch.
During the summer and fall, the nape patch disappears
due to heavy wear of the long, white feathers,
revealing short, black feathers beneath,
but the bold white nape patch reappears by midwinter.
Juvenile males also have white nape patches,
though white forecrowns are not evident before their
second winter.
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While all scoters are relatively silent,
Surf Scoters are the least vocal.
Courting drakes are given to
low, throaty croaks, and bubbling whistles or gurgles,
with the gurgling notes described as similar to water dropping in a cavern.
Reasonably large winter flocks congregate off ocean beaches, where the
ducks can be indifferent to intense human activity.
Their flock sizes and flight formations are not unlike Black Scoters,
thus the two species can be difficult to separate at a distance.
However, the loud humming wingbeats of Surf Scoters are slightly slower,
and they seldom fly in lines, tending instead to bunch up in large,
irregular formations.
When the wind falls away, rising from the water is rather
difficult, but their flight is strong and swift once underway.
During migration, and in calm weather
with light winds, the ducks are apt to fly at great heights,
whereas windy and stormy weather induces them to fly close to the waves.
Rarely diving in water that exceeds 30 feet deep,
Surf Scoters forage in the zone of breaking waves,
and habitually dive through foaming wave crests.
Gulls, especially Glaucous-winged Gulls, often force
surfacing ducks to relinquish their prey, thus flocks
frequently dive in unison.
This possibly promotes synchronous surfacing,
when groups are less likely to be kleptoparasitized than individual ducks due to
the swamping effect.
Blue mussels constitute nearly 30 percent of their marine diet--the stomach of
one scoter was crammed with 1,100 small blue mussels.
Immense rafts congregate in regions supporting extensive mussel beds.
Hundreds of thousands winter in the coastal waters off British
Columbia alone, and 200,000 scoters could consume about 43
tons of mussel meat daily.
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The most abundant wintering Pacific coast scoter,
Surf Scoters favor shallow waters in bays, estuaries
and river mouths. Even so, some winter inland,
and the ducks can be fairly numerous on the Great
Lakes. Vagrants regularly appear in Europe.
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