Two sets of fresh eggs, numbering three and four, respectively, were taken on June 11, 1913; the male incubating one and the female the other. Both birds when disturbed fluttered off the nest like other sandpipers. The nests were cavities on small mounds of tundra lined with dry willow leaves.
Eggs.—I have been unable to locate any eggs of the rufous-necked sandpiper and do not know what became of the two sets referred to above. Joseph Dixon (1918) implies that the eggs resemble those of the spoonbill sandpiper.
Plumages.—In the downy young the crown and upper parts are variegated with black, "tawny" and "warm buff"; the forehead, superciliary stripe and sides of the head and neck are "warm buff"; the under parts are white, washed on the breast with pale buff; a narrow median stripe on the forehead and a broader loral stripe are black. The specimen described above was taken at Cape Serdze, Siberia, on July 16, and shows the beginning of the juvenal plumage; the back and scapulars are well covered with young feathers and the wings are well started, though the bird is still very small and mostly downy. The feathers of the back and scapulars are black, broadly edged with "hazel," and the scapulars are tipped with white.
Older young and subsequent plumages are well described by Robert Ridgway (1919). The molts are apparently similar to those of other species in the genus. The postnuptial molt of the body plumage occurs mainly in August and the wings and tail are molted in January and February. I have seen birds in winter plumage as early as August 13 and as late as March 15. Probably the prenuptial molt of the body plumage takes place in April. In fresh nuptial plumage the bright colors of the upper parts are veiled with "drab-gray" tips, which soon wear away. There is much individual variation in the amount of rufous on the head, neck, and breast. Mr. Dixon (1918) says that in this plumage the rufous-necked sandpiper looks very much like the spoonbill sandpiper; and, as its behavior is similar, it might easily be mistaken for it.
DISTRIBUTION
Breeding range.—Northeastern Siberia (probably the delta of the Lena River and the shores of the Sea of Okhotsk, certainly at Providence Bay, Kooshka, and Cape Serdze); and northwestern Alaska (Cape Prince of Wales, Wainwright, and probably Nome.)
Winter range.—The Malay Archipelago, the Philippines, and Australia.
Migrations.—First arrivals reach Gichiga, Siberia, May 28, and they are mostly gone by September 11. They pass Bering Island late in May and again during the first half of September. One taken by G. Dallas Hanna on St. Paul Island, August 27, 1920. They have been taken in the Philippines as early as August 13. Japan, China, and Lake Baikal are included in the migration route.