Seward, Alaska
This afternoon I spied a very light-colored, small sandpiper
feeding with a flock of about 40 chattering ROCK SANDPIPERS and three droopy-billed, gray-brown (dun-colored) DUNLINS.
A SANDERLING! This is an uncommon shorebird for Seward any
time of year. Homer reported one for their CBC on December 17 that was also
with Rock Sandpipers.
A small population of Sanderlings nests in the high arctic
tundra on the North Slope near Barrow. During migration, some stage in the
Copper River Delta and some migrate through the Aleutian Islands, with sporadic
winter sightings such as this. According to the Alaska Species Ranking System
Summary Report, this species is in decline and of concern.
The Rock Sandpipers nest in remote islands and along the coast
of western Alaska. It sure is convenient for them to come here instead of me
flying to the Pribilofs or Aleutian Islands!
Most Alaskan shorebirds migrate south as early as July to
escape winter, yet these hardy Rock Sandpipers with their Dunlin and Sanderling
pals seemed quite at home despite our variable and often severe winter weather.
The Rock Sandpipers winters farther north than any other North American
shorebird.
The Rock Sandpiper flock consisted of the very light gray
Pribilof Rock Sandpiper (Calidris ptilocnemis ssp ptilocnemis) and two darker subspecies that
may be the Aleutian Rock Sandpiper (ssp couesi), and/or the intermediate, tschukschorum. These
subspecies are quite complicated, variable, and are still under review. Thanks
to Luke DeCicco for his help!
The busy sandpipers worked along the high tide line, pulling
out tiny tidbits to eat. I watched one Rock Sandpiper pluck a fingernail-sized,
pink Macoma clam out of the cobble beach. Even though the clam was sideways,
somehow the bird managed to open wide and gobble it down, shell and all, and
without pause or apparent discomfort, continue to search for more.
An Alaska Department of Fish and Game publication noted that
the Baltic Macoma (Macoma balthica) is an important food source for coastal
birds, especially during winter and migration stopovers. It also states that
the tiny clam comprises the entire diet of the Pribilof Rock Sandpiper while
wintering in Cook Inlet.
Seward regularly hosts small flocks of over-wintering Rock
Sandpipers, occasionally Dunlins, and rarely Sanderlings. But it’s always a
thrill to watch these incredible tough guys leap-frogging along the beach and
especially to hear them gaily chattering on a short winter day like today.
Happy Birding!
Carol Griswold
Seward Sporadic Bird Report Reporter
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