Part 56

Voice.--Doctor Stejneger (1885) says that “the call note is a clear, penetrating drrrriit.” Mr. Jourdain adds: “The call note is described by Whistler as a soft twip, and the alarm note as a sort of chatter of two syllables corr up, not unlike the note of a frog and compared by Osmaston to that of a nightjar. It is uttered usually on the wing and also occasionally on the ground.”

DISTRIBUTION

Range.--Eastern Asia and Oceanica; accidental in Alaska.

Breeding range.--This race of the Mongolian plover breeds chiefly in northeastern Siberia (Cape Serdze, Bering Island, Kamchatka, and the Commander Islands); probably also in Dauria and Mongolia.

Winter range.--The winter range includes the Philippine Islands, the Moluccas, New Guinea, and northern Australia.

Migration.--The species has been noted to arrive in spring at Yokohama, Japan, on April 28, and at Bering Island, on May 11. A late fall date on Bering Island is September 22.

Casual records.--On June 11, 1925, an adult male was collected at Cape Prince of Wales (Bailey). Two specimens were taken by C. G. Harrold on Nunivak Island, Alaska, in 1927, one on August 14, and one on September 1; others were seen on August 14 and September 11 and 13. These are the only North American records.

Egg dates.--Bering Island, June 4. Siberia, June 9.

PAGOLLA WILSONIA WILSONIA (Ord.)

WILSON PLOVER

HABITS

All along the Atlantic coast from New Jersey to Florida is a broken chain of sea-girt islands, with broad or steep, sandy or shelly beaches on the ocean side, backed in many places by shifting sand dunes and bordered on the inner or bay side by wide marshes of waving grass or extensive flats exposed at low tide. Here, on the broader, more open sand flats, among a scattered array of shells, pebbles, and other débris cast up by the sea, or in the flat hollows among the sand dunes, this little sand plover makes its home, within sound of the pounding surf and fanned by the ocean breezes that carve the dunes into fantastic shapes. Here, if we love to wander in these seaside solitudes, we may see this gentle bird running along the beach ahead of us, his feet twinkling so fast that we can hardly see them; he is unafraid, as he stops and turns to watch us; the black bands on his head and breast help to obliterate his form and he might be mistaken for an old seashell or bit of driftwood; but, as we draw near, he turns and runs on ahead of us, leading us thus on and on up the beach. There is an air of gentleness in his manner and an air of wildness in his note as he flies away.

Spring.--As the northern limit of the winter range extends well up to central Florida, the Wilson plover has not far to migrate. It is an early migrant. We saw it in Pinellas County, Fla., as early as February 7, where a few were present all winter. C. J. Pennock’s notes record it at Charlotte Harbor on February 21 and 24, on two successive years. Arthur T. Wayne (1910) says that it arrives in South Carolina late in March; his earliest date is March 26.

Courtship.--During the month of March, when this species became common in the vicinity of Tampa Bay, Fla., I had some opportunities to watch its simple courtship display. A male shot on March 14 had sexual organs developed nearly to full breeding size and many of the birds were in pairs. In making the display the male runs around the female in a crouching, hunchbacked attitude, with the head lowered, the tail depressed and spread, and the wings drooping. The female seems indifferent at first, but finally she accepts the caresses of the male. They seem to be preoccupied in their love affairs and allow a close approach.

Nesting.--On the sandy reefs and broad ocean beaches of the outer islands about Bulls Bay, S. C., we found several nests of Wilson plover on May 22 and 23, 1915. The nests were on the higher portions of the beaches where the dry, sandy plains were sprinkled with bits of broken shells, small stones, and pieces of driftwood or other rubbish and where a few scattered weeds and grasses were the only signs of vegetation. The nests were usually placed near some such object, or partially sheltered by a few blades of grass, but some were out on the open sand or in the flat sandy hollows between the dunes; they were always beyond the reach of ordinary tides. Oyster-catchers and least terns were nesting in the same localities and not far away willets were nesting in the grassy places.

Among the Florida Keys, on May 8, 1903, we found a small colony nesting on Lake Key; there were beaches of finely broken shells surrounding a small shallow pond, more or less overgrown with small, scattered red mangroves. A colony of least terns were nesting here and a few pairs of black-necked stilts. Four nests of the plover were found, one out on the open beach among the terns’ nests and the others under the shelter of little mangrove seedlings. These and all the other nests of Wilson plover that I have found were mere hollows in the sand with no apparent attempt at lining, but others have occasionally found them evidently lined with bits of broken shell. Henry Thurston (1913) found a nest “snuggled closely to the stump” of a “ripped up” palmetto; the eggs were “resting in a small hole that had been scooped out in the sand and adorned with a few twigs.” He left this nest and returned later in an attempt to see the female leave the nest. As, he “got within a few yards the male, unobserved before as he was facing him and was therefore practically invisible, piped several notes. Swiftly and mouse-like the female glided from her treasures, crouching low beside the stump and did not stand erect until she reached the water’s edge.”

The Wilson plover might almost be said to nest in colonies, although the nests are usually not close together; N. B. Moore says in his notes that they are never nearer than 20 yards apart. Oscar E. Baynard (1914) found a colony of at least 50 pairs nesting on a bank of white sand, probably half a mile long and barely a foot above high-water line. He relates an interesting experience in changing eggs from one nest to another. One of a set of three heavily incubated eggs that he had taken hatched out in his possession; as he could not find the nest from which they came, he hunted up another nest which contained fresh eggs; and following is his account of what happened:

I took these eggs and placed the young bird and my two eggs in their place, and then moved off and sat down to watch developments. In a few minutes the mother bird ran up to the nest, looked hard at the young bird, which had run off about 2 feet from the eggs, circled the nest several times, and then squatted down on the two eggs and began calling softly to the young bird. In a few minutes he crept up to the old bird. She looked him over for fully two minutes, then decided to adopt him, raked him under her out of the sun, and settled down as contentedly as if the family were really her own. Two days later I ran the boat close to the beach opposite this nest. The old bird ran off, and up jumped three young and took off up the beach after her.

Donald J. Nicholson tells me that he once found a nest “about three-quarters of the way up the side of a sand dune under the shelter of a small bunch of grass.” He has also found this plover breeding on Merritts Island, Fla., “on the exposed sandy patches along the Indian River and around the water holes throughout the island”; here some of the nests were sheltered among open growths of pickerel weed or Salicornia.

Dr. Frank M. Chapman (1891) found this bird breeding commonly near Corpus Christi, Tex., and says: “A nest found April 25 was placed in some short grass about 50 feet from the water. It was composed of a few straws placed at the bottom of a slight depression in the sand, and contained three fresh eggs.”

Eggs.--The Wilson plover ordinarily lays three eggs, often only two, and very rarely four; I have a set of four eggs in my collection, taken by Dr. Eugene E. Murphey on the coast of South Carolina. N. B. Moore says in his notes that a day often intervened between the laying of eggs, once an interval of two days occurred and in one nest the third egg was laid on the ninth day after the first. The eggs are ovate to short ovate in shape and they have no gloss. The ground colors vary from “cream buff” to “cartridge buff.” They are usually thickly and quite evenly covered with small spots, small irregular blotches and scrawls of black, with a few similar, underlying markings of pale shades of “Quaker drab.” The measurements of 66 eggs average 35.7 by 26.2 millimeters; the eggs showing the four extremes measure =38.5= by 26, 37 by =27=, =31.5= by 26, and 34 by =25= millimeters.

Young.--N. B. Moore observed that the period of incubation is 24 or 25 days. I have no data showing that the male shares in the duty of incubation, but he certainly shows considerable interest in the care of the young. The young are able to leave the nesting hollow soon after they are hatched and they are strong and swift runners, as well as adept in the art of hiding. The female is a past master in the art of decoying an intruder away from her young. Mr. Thurston (1913) has described this strategy very well, as follows:

As I approached this strip, seemingly from nowhere there appeared a female plover, calling plaintively. Now I knew that the season of nesting had begun. She was soon joined by a male and another female that chorused with her their wishes for my departure. How she coaxed me to follow her! This I did for a time, trailing behind as she struggled along on one leg, the other crumpled under her. Tediously she kept ahead, calling--sobbing, I should have said--one of the most pathetic yet beautiful notes I have heard. Surely if ever there was a picture of parental distress it was she. Finally, as though exhausted, she sank to the sand and lay on her side gasping. The other two flew back and forth overhead, whistling plaintively, but she heeded them not, nor my approach, and lay there panting. I was sure now that she was tired by her exertion and hurried to catch her, only to learn that she was “playing possum.” She allowed me to almost touch her, and fluttered off again. Evidently she was not satisfied that her nest was safe and she tried new tactics this time. With seemingly broken wings that trailed as though helpless at her sides, she started down the beach and once more I followed after, but this time increased my speed. As I had about caught up with her she gave a joyous whistle, sprang into the air, and those wounded wings carried her like a bullet around a point of wooded land and out of sight. She had accomplished her purpose, as I had hopelessly lost the place from which she started. Search as I might, and did, I could not find it.

Plumages.--The upper parts of the downy young Wilson plover are of about the same color pattern as the egg to make it equally invisible on the sand. The crown, back, rump, wings, and thighs are “cream buff,” mottled with black; the forehead, sides of the head, and under parts are white; there is a broad white collar around the neck, and the outer joint of the wing is white.

The juvenal plumage, in what specimens I have seen, July 20 to 27, is much like that of the adult female in winter, but the colors are duller and the breast band is incomplete or only suggested. Perhaps earlier in the season these birds might have shown buffy edgings which had since worn away. Probably a postjuvenal molt takes place, but I have not been able to trace it. In the first winter plumage the sexes are alike; but at the first prenuptial molt, in February and March, the male assumes, partially at least, the black markings on the head and breast. At the next complete molt, the first postnuptial, the adult winter plumage is acquired.

Adults have an incomplete prenuptial molt, from January to March, involving the body plumage, and a complete postnuptial molt, from July to October. The sexes are quite unlike in nuptial plumage, the black markings on the head and breast of the male being replaced by “wood brown” in the female. In winter they are much alike, but I believe that in fully adult males there is always more or less black in the breast band.

Food.--Audubon (1840) says of these birds:

They feed fully as much by night as by day, and the large eyes of this, as of other species of the genus, seem to fit them for nocturnal searchings. Their food consists principally of small marine insects, minute shellfish, and sand worms, with which they mix particles of sand.