Some European writers have called it the Siberian pectoral sandpiper, which its resemblance to our common bird of that name seems to warrant. It is so much like our pectoral sandpiper in appearance, behavior, and haunts, that it has probably often been overlooked; it may therefore occur on our northwestern coast much oftener than we suspect.
Nesting.—The sharp-tailed sandpiper is supposed to breed in Mongolia and eastern Siberia; it has been seen and collected on its breeding grounds in northeastern Siberia, Cape Wankarem, the Chuckchi Peninsula, and the Kolyma Delta, but apparently its nest has never been found and its eggs are entirely unknown.
Plumages.—The downy young is entirely unknown. This sandpiper is handsomely and richly colored in any plumage, but the rich buff and bright browns of the juvenal plumage are particularly noticeable. The body plumage is molted in the fall, the wings and tail in late winter, and the body plumage is partially molted again in the spring. The plumages are well described in the manuals.
Food.—Preble and McAtee (1923) report on the food of this species, as follows:
Eight well-filled and one nearly empty stomach of the sharp-tailed sandpiper are available to illustrate the food habits. This number is too small to furnish reliable results, and too great dependence must not be placed in data as to the relative ranks of food items as here stated. The percentages found for the limited material, then, are flies (Diptera), 39.1 per cent; crustaceans, 18.1 per cent; mollusks, 14.2 per cent; caddisflies, 11.8 per cent; beetles, 8.8 per cent; Hymenoptera, 1.8 per cent; and vegetable matter, 3.9 per cent. Mr. Hanna notes that flocks of this species frequent the seal-killing fields, feeding on fly maggots, a statement receiving confirmation from stomach analysis.
Behavior.—Dr. E. W. Nelson (1887) tells us a little about the habits of this rare species, as follows:
They were nearly always associated with maculata, whose habits they shared to a great extent. When congregated about their feeding places they united into flocks of from ten into fifty, but single birds were frequently flushed from and they were rarely shy. On October 1, 1880, they were found scattered singly over the marsh, and arose 30 to 40 yards in advance, and made off with a twisting flight, uttering at the same time a short, soft, metallic pleep, pleep, and pursuing an erratic, circuitous flight for a time they generally returned and settled near the spot whence they started. On the shore of Siberia, near North Cape, we found these birds very common, scattered over damp grass flats near the coast, the 1st of August, 1881. The ground was covered with reindeer tracks, and among these the sharp-tailed snipe were seen seeking their food. They were very unsuspicious and allowed us to pass close to them, or circled close about us. From their movements and other circumstances I judged that this district formed part of their breeding grounds, whence they reach the neighboring coast of Alaska in fall.
Field marks.—The sharp-tailed sandpiper most closely resembles the pectoral sandpiper, but it can often be recognized in the field by the more ruddy color of the upper parts. Most of the feathers of the shoulders, scapulars and secondaries are broadly edged with chestnut; these edgings are paler in winter. The bright chestnut crown, streaked with black, and the ruddy brown suffusion on the chest and sides, might be recognized under favorable circumstances.
Fall.—Not much seems to be known about the spring migration, but the fall migration is fairly well marked. Doctor Nelson (1887) says: