forms no nest, but makes a “cavity in the moss, in a place sheltered
from the north winds and exposed to the full rays of the sun, usually
near the margins of small ponds formed by the melting of the snow, and
surrounded by short grass.”
_Eggs._--[AUTHOR’S NOTE: The semipalmated plover lays four eggs, often
only three. They are ovate pyriform to subpyriform in shape, with
little or no gloss. The ground colors vary from “buckthorn brown” or
“clay color” to “cartridge buff,” “olive buff” or “pale olive buff.”
They are boldly and irregularly marked with small or large spots or
blotches of black, brownish black or very dark browns; some eggs
are heavily blotched with “warm sepia” or “chestnut brown”; there
are usually a few small underlying spots of “pale drab gray.” The
measurements of 100 eggs average 33 by 23.5 millimeters; the eggs
showing the four extremes measure =36.2= by 24.3, 35.5 by =25.5= and
=29.5= by =22= millimeters.]
_Young._--The duration of incubation is not known. In the allied ringed
plover of Europe the period of incubation is stated by Dr. W. H.
Bergtold (1917) to be 22 and 23 days.
In the past it has generally been assumed that, with the exception in
the case of the phalaropes, the female among the shore birds incubates
the eggs and takes charge of the young. Joseph Dixon (1927) says:
“After several seasons’ experience with breeding shore birds in the
north the writer has come to believe that in more of our Limicolae
than is generally known it is a common practice for the males to take
a leading part in domestic duties not only in incubation but also in
the care and training of the downy young.” With specimens in hand
during the breeding season, he found incubating patches in the male
semipalmated plover, and he says that “the males did a large part of
the incubation and that it was the males that were the most fearless in
the face of danger when caring for their young.”
P. B. Philipp (1925), on the other hand, studying the nesting bird
in the Magdalens, writes: “I judge that the female does most of the
incubating, three birds shot off the nest being of this sex.” H. S.
Swarth also sustains the side of the female, for he writes: “With
binoculars it is often possible to distinguish the sexes of the
plovers, and it could be seen that it was the male who tired first in
such efforts [shamming injury] to deflect danger from the nest. Even
when he withdrew entirely, the female continued her protests until we
were well out of her territory.” Dr. L. B. Bishop (1900), however,
reconciles both points of view, for he says: “Bare pectoral spaces
showed that both sexes assisted in incubation.”
The young leave the nest and run after the parents almost as soon as
they are hatched. Bishop (1900) in the Yukon River region found an egg
that was already pipped. He says: “I removed the young bird from the
shell, and within half an hour the down was almost dry, the eyes were
open, and it could hop about on its ‘knees.’”
Dr. W. H. Osgood (1909) reports the following observation by N.
Hollister on a downy young of this species: “Although it was perfectly
able to run about as fast as the adults, it at once lay flat to the
ground when approached, with head extended forward in the sand, making
it very difficult to see, so closely did it match the ground in color.”
The actions of the parent incubating the eggs when a human intruder
appears is well told by H. S. Swarth in a communication, as follows:
The breeding bird skulked from the nest at the first
appearance of an intruder, and, after performing an
unobtrusive retreat to a distant point, launched out in
conspicuous protest at the trespass. The call notes served
to summon the mate, and sometimes even another pair of
birds, all hovering about overhead or racing close by
over the sand. A liquid call note, not particularly loud,
was uttered constantly, and both birds of a pair would go
through the form of pretended injury, dragging themselves
over the sand with drooping wings and spread tail.
In another case--
A bird was flushed, as it had been many times before, at
a point 300 yards or more above the water line, and I sat
down quietly to watch her from the shelter of a scrubby
willow. She flew to a distance, but returned in a few
minutes, to run aimlessly about over the gravel nearby.
Gradually she drew away, running over and between logs and
other drift, her manner changing from one of noisy protest
to furtive withdrawal behind any available cover. Finally,
about 20 minutes after I began to watch, she settled down
on the gravel, as it developed, upon the eggs.
At Seal Island, off the southern point of Nova Scotia, I found
several breeding pairs of semipalmated plover, here, probably, at
its most southern breeding place. On one occasion I came upon a bird
that performed the usual wounded bird act, falling on its side and
fluttering its wings as if badly injured. Presently it made off,
fluttering and dragging its spread tail on the ground, keeping up this
method of progression for over a hundred yards, although I had stood
still. I then walked in the opposite direction and found a downy young
running off in company with the other parent.
On another occasion at Great Caribou Island, Labrador, one of these
birds appeared greatly excited at my presence, alighting near me,
bobbing nervously, and protesting in conversational tones. Then it flew
away, but immediately returned and flew by several times within a few
yards, apparently in great fury, but not daring to hit me.
_Plumages._--[AUTHOR’S NOTE: In natal down the young semipalmated
plover is darkly colored above. The entire upper parts, from forehead
to rump, are mottled with “deep olive buff” and black. The auriculars
and a broad band encircling the back of the head are velvety black;
there is a distinct black stripe from the bill to the eye and from the
lores to the auriculars. A spot under the eye, a ring around the neck,
and the entire underparts are pure white.
In fresh juvenal plumage the crown, back, rump, scapulars, and wing
coverts are “buffy brown,” narrowly edged with creamy or buffy white,
the edgings broadest on the wing coverts; the lores, cheeks, and a
broad band across the chest are “buffy brown” to “sepia”; the forehead,
throat, a ring around the neck, and the entire underparts are white;
the tail is like the adult, but tipped with “pinkish buff.” The buffy
edgings mostly wear away before the partial postjuvenal molt, which
occurs in late fall. The first winter plumage is like the adult winter
plumage, except that some of the juvenal wing coverts are retained and
the head is as in the juvenal. At the next molt, a partial prenuptial,
the plumage becomes practically adult; only a few old wing coverts
remain.
Adults have a partial prenuptial molt in the spring involving the body
plumage, some scapulars and wing coverts, and a complete postnuptial
molt from July to December; I have seen the wings molted as early as
July 30 and as late as December 10. The sexes are alike in immature
and winter plumage and not very different in spring, when the black
markings of the female are duller or mixed with grayish brown. In both
sexes in winter the black markings are replaced by grayish brown.]
_Food._--The semipalmated plover is an active feeder and in this way
is sometimes beneficial to man. In the stomachs of 12 birds shot on
beaches I have found worms, small mollusks (_Litorina_, _Mytelis_),
various crustaceans (_Orchestia_, _Gammarus_, _Limnoria_), and insects.
W. L. McAtee (1911) says that this bird eats the larvae of the salt
marsh mosquito (_Ædes sollicitans_). Samuel Aughey (1878) investigated
the relation of birds to insects in Nebraska during the great invasion
of Rocky Mountain migratory locusts on the western prairies and plains
of the United States from 1873 to 1876. Of 11 stomachs of this species
examined, he found the average number of locusts in each was 38; of
other insects, 19. Junius Henderson (1927) states that this plover “on
coast, feeds largely on crustaceans, mollusks, eggs of marine animals,
and insects; interior, feeds on locusts and other Orthoptera, and many
other insects.” Audubon (1840) says: “At this period (September) they
are now and then observed on plowed lands, where they appear to procure
different species of seeds and insects.”
_Behavior._--The behavior of this bird during courtship and in the care
of the eggs and young has already been described. On beaches and mud
flats it is sometimes difficult to see, notwithstanding its strikingly
marked plumage. As the piping plover matches the dry sand, so the
semipalmated plover matches the wet sand, its favorite feeding grounds.
Here one may walk almost onto them without seeing them if they stand
motionless, as they often do. While sleeping on the dry sand, even with
the black and white markings in plain sight, they are also difficult
to see. W. V. Praeger (1891) writes as follows of a wounded bird he
observed hiding in a hollow in the sand:
While admiring the perfect blending of its brown shades
with the surroundings I saw in its white rings one of the
commonest objects of the seashore--the empty half of a
bivalve shell. The white about the base of the bill was the
“hinge,” the collar the outer rim, and the top of the head
the cavity of the shell filled--as they usually are--with
sand.
Gerald H. Thayer (1909), writing of the very similar ringed
plover of Europe, speaks of the “eye-masking and ‘obliterative’
shadow-and-hole-picturing pattern.”
Although this bird migrates and feeds both by day and night, it often
happens that a flock is discovered at sunset out of reach of the tide,
clustered together as if they had settled down for the night. That
they spend the night there in some cases at least is shown by William
Brewster (1925), who says: “I have repeatedly observed them standing
motionless, singly or in clustering groups, on some mud bar to which
they had thus returned, keeping them in view until it was too dark to
see them longer and finding them all there the next morning.”
During high tide, when their best feeding grounds are covered, these
birds, like many other shore birds, are very apt to be found sleeping
on the upper beach above the reach of the waves. The flock is generally
huddled closely together, some standing but many squatting with their
breasts resting on the sand, often in the lee of bunches of seaweed.
While some sleep with heads turned to one side and bills thrust into
the feathers of the back in the usual manner of birds, others sleep
with heads sunk down between the shoulders. Generally some of the flock
are awake and on the lookout, while the others open their eyes from
time to time.
In flight the flocks are often compact, twisting and turning as if
animated by a single thought, but they also fly in loose order. On
alighting they at once spread out on the sand in true plover fashion,
and do not, like sandpipers, keep together and move along close to the
wave line. Another plover habit which at once distinguishes them from
sanderlings or other sandpipers of a similar size, is that of running
about with heads up and dabbing suddenly at the ground from time to
time instead of moving along with heads down diligently probing the
sand. With erect figures they run about in various directions, often
pausing and standing still as if in thought, occasionally jerking or
bobbing their heads and necks and ever and again swiftly dabbing at
some morsel of food.
The semipalmated plover associates most frequently with the least and
semipalmated sandpipers, but it also flies with sanderlings and other
larger waders. Sometimes these birds fly in mixed flocks, but as a rule
the ringnecks keep by themselves in flight, but readily join other
species on the ground.
On the seacoast the ringneck frequents the outer beaches, the shores
and mud flats of estuaries and tidal pools, and the sloughs in the
salt marshes. Inland it visits similar regions on the shores of lakes
and rivers as well as upland fields in search of food. As I have said
elsewhere (C. W. Townsend, 1905):
Like all shore birds also, the ringneck is often
exceedingly fat in the autumn, and I have known the fat
of the breast to split open when the bird struck the
ground after being shot when flying at a height. The fat
is not only everywhere under the skin, but it develops
all the viscera, and the liver is often pale from fatty
infiltration. How birds under these circumstances are able
to fly so vigorously on their long migrations, or even to
fly at all, is certainly a mystery.
_Voice._--The courtship song has already been described. The common
call note is a clear, rather plaintive, whistle of two notes, very
distinctive and frequently emitted while the birds are on the wing. It
is expressed by Hoffmann (1904) by the syllables _chee-wee_; Nichols
(1920) writes it _tyoo-eep_. It is cheerful and businesslike compared
with the sweet and mournful whistle of the piping plover. When calling
to others as they alight, or when standing on the sand, they often emit
a single note, sweet and clear, but at times harsh and rasping.
_Field marks._--The semipalmated plover is easily distinguished in the
field from the killdeer by its smaller size, its single neck ring,
and by the absence of the rufous color on the rump. Its darker colors
distinguish it from the piping plover. From the sandpipers, even at a
distance on the sand, it is distinguished most readily by its plover
behavior, as already described. In flying they show a faint white line
on the wings which contrasts with the general brown of the upper parts.
The neck ring is noticeable both in the flying and walking bird, and
the orange yellow of the tarsi and base of the bill can be made out
with glasses. In the young, which arrive on the Massachusetts coast
about a month behind their elders in the autumn migration, the ring is
gray instead of glossy black, and the tarsi are pale yellow. It may be
distinguished from the Wilson’s plover by the fact that that bird has a
much longer bill, wholly black.
_Game._--Although this little plover was formerly shot as game in
the same manner as is described under the least and semipalmated
sandpipers, it is now protected at all seasons. Besides its value as a
destroyer of harmful insects, its greatest value is aesthetic. On the
beaches of the sea and lakes its graceful flight, handsome plumage,
and confiding ways are a source of great pleasure, and on this account
alone it is worthy of protection for all time.
_Fall._--The fall migration, as stated above, is a long and leisurely
one, differing markedly in this respect from the spring migration.
When a favorable spot is found, abounding in food and free from
disturbances, these birds are apt to tarry there for some time. Here
they grow fat and here they indulge in courtship performances as if it
were the spring of the year. On beaches and marshes, where in former
times gunners, hidden in blinds, were lurking to destroy them, all is
now peace and quiet for these little birds, and their journey southward
is undisturbed.
Of the fall migration Wells W. Cooke (1912) writes:
At one of the most southern breeding places near York
Factory, Keewatin, in 1900, the most advanced young were
still in the downy stage July 10 (Preble), and yet by this
time the species is already in full fall migration, and the
earliest individuals have appeared several hundred miles
south of the breeding range. * * * Though most semipalmated
plover migrate early, a few stay until freezing weather.
The adults migrate first, while the young rarely arrive on the
Massachusetts coast before August 15.
_Winter._--Although the majority of the species winter south of the
United States, as is shown under “winter range,” some are to be found
at this season on the shores of the Southern and Gulf States earning
their living in pursuit of their small prey.
DISTRIBUTION
_Range._--North and South America.
_Breeding range._--The breeding range of the semipalmated plover
extends north to Alaska (Morzhovia Bay, Hooper Bay, and the Colville
delta); northern Mackenzie (Mackenzie delta, Lower Anderson River,
Franklin Bay, Horton River, and Bernard Harbor); Keewatin (Whale
Point); Franklin (Annanostook and Kingnite Fjord); Victoria Land;
Baffin Island; and western Greenland (Disco). East to western Greenland
(Disco); Labrador (Port Burwell, Okak, and Tessiujaksoak); Newfoundland
(Straits of Belle Isle); eastern Quebec (Upper Hamilton River,
Wapitagun Island, Magdalen Islands, and Mingan Islands); and Nova
Scotia (Sable Island). South to Nova Scotia (Sable Island and Yarmouth
County); probably rarely New Brunswick (Grand Manan); northern Ontario
(Moose Factory); Manitoba (Hayes River and Fort Churchill); southern
Mackenzie (Artillery Lake); Yukon (Lake Marsh); and British Columbia
(Graham Island). West to British Columbia (Graham Island); and Alaska
(Berg Bay, Glacier Bay, and Morzhovia Bay).
In common with several other shore birds, nonbreeders remain throughout
the summer in southern latitudes. At this season they have been taken
or observed south to Venezuela (Margarita Island), Galapagos Islands,
Costa Rica, the West Indies, and Jalisco (Ocotlan), while they
frequently are fairly common on the coasts of the United States and
at points in the interior, Ohio (Lakeside and Oberlin), and Michigan
(Detroit).
Kumlien and Hollister report obtaining young not yet able to fly
at Lake Koshkonong, Wis., but if their identification was correct,
this record must be considered accidental. The species also has been
reported in summer from eastern Siberia (East Cape), where it may breed.
_Winter range._--The winter range extends north to California (rarely
Palo Alto); Texas (Brownsville and Corpus Christi); Louisiana (State
Game Preserve); Mississippi (Biloxi); probably Alabama (Coffee Island);
South Carolina (Dewees Island); and Bermuda (Somerset). East to Bermuda
(Somerset); South Carolina (Port Royal); Georgia (Savannah, Blackbeard
Island, and Darien); Florida (Amelia Island, Mayport, Daytona, Mosquito
Inlet, Upper Metacumbe Key, and Key West); the Bahama Islands (Abaco,
New Providence, Watling Island, and Great Inagua); Haiti (Monte Cristi,
and Samana); Porto Rico; the Lesser Antilles (Anegada, Sombrero Key,
St. Bartholomew, Carriacou, and Trinidad); Guiana (Abary River and
Cayenne); Brazil (Island of Mixiana, Cajetuba Island, Pernambuco,
Bahia, Abrolhos Island, Peranagua, and Santa Catarina); and Argentina
(Puerto Deseado). South to Argentina (Puerto Deseado and Jujuy); and
Chile (Calbuco). West to Chile (Calbuco, Coquimbo, and Moreno Bay);
Peru (Chorillos, Ancon, Trujillo, and Payta); Ecuador (Puna Island,
Guayaquil, and Santa Elena); Galapagos Islands (Albemarle and Narboro);
Costa Rica; Honduras (Manatee Lagoon); Guatemala (Chiapam); Oaxaca (San
Mateo); Sinaloa (Mazatlan); Lower California (La Paz); and California
(San Diego, San Pedro, Saticoy, Pacific Grove, and rarely Palo Alto).
_Spring migration._--Early dates of spring arrival are: Virginia,
Arlington Beach, April 30; District of Columbia, Washington, May 3;
Pennsylvania, Wayne, May 5, and Erie, May 8; New Jersey, Cape May,
April 24, Camden, May 5, and Long Beach, May 10; New York, Long
Island, April 19, Orient, May 2, Geneva, May 5, and Rochester, May 16;
Connecticut, New Haven, May 1, and Fairfield, May 4; Rhode Island,
Newport, April 15; Massachusetts, Rehoboth, April 21, Monomoy Island,
April 28, and Dennis, May 5; Maine, Saco, May 5; Quebec, Quebec City,
May 6, Montreal, May 19, Godbout, May 28, Eskimo Point, June 3, and
Fort Chimo, June 11; Nova Scotia, Pictou, May 9, and Antigonish, May
15; Franklin, Winter Island, May 31; Missouri, St. Louis, April 2,
and Kahoka, April 4; Illinois, Rantoul, April 9, near Chicago, April
25, and Cantine, April 26; Indiana, Denver, May 1, Terre Haute, May
5, and Bloomington, May 9; Ohio, Sandusky, April 20, Cleveland, April
21, and Oberlin, April 24; Michigan, Ann Arbor, May 5, Jackson, May
8, and Grand Rapids, May 9; Ontario, Toronto, April 21, Hamilton,
April 24, Ottawa, May 9, and Guelph, May 15; Iowa, Sioux City, April
22, Ogden, April 24, and Emmetsburg, April 27; Wisconsin, Madison,
May 5; Minnesota, Heron Lake, May 8, and Minneapolis, May 11;
Kansas, Lawrence, April 22, Emporia, April 25, and McPherson, May 3;
Nebraska, Lincoln, April 27; South Dakota, Vermilion, April 20, and
Brookings, May 8; Manitoba, Brandon, April 28, and Reaburn, May 9;
Saskatchewan, Lake Johnston, May 10; Mackenzie, Fort Simpson, May 16,
and Fort Resolution, May 23; Alberta, Veteran, April 24, Camrose,
May 6, Tofield, May 12, Peace River, May 20, and Fort Chipewyan, May
23; northern California, Eureka, April 17; Nevada, Smoky Creek, May
4; Washington, Destruction Island, April 24, and Grays Harbor, April
30; British Columbia, Ucluelet, April 28, and Comox, May 3; Yukon,
Forty-mile, May 23; and Alaska, Admiralty Island, May 8, Bethel, May
10, Bristol Bay, May 15, Coronation Island, May 15, and Hooper Bay, May
19.
Late dates of spring departure are: Brazil, Cajetuba Island, April
18; Colombia, Sabanilla, March 27; Porto Rico, Luquillo, March 5, and
Vieques Island, March 30; Haiti, Samana, April 13; Bahamas, Abaco,
April 28, and Green Cay, April 29; Florida, Daytona Beach, May 25,
Punta Rassa, May 25, and Pensacola, May 30; Georgia, Savannah, May
13; South Carolina, Kiawah Island, June 2, and Bulls Bay, June 7;
North Carolina, Pea and Bodie Islands, May 17; Cape Hatteras, May 20,
and Raleigh, May 22; Virginia, Cape Charles, May 24, Smiths Island,
May 25, and Wallops Island, May 30; District of Columbia, Alexander
Island, May 22, and Washington, May 25; Maryland, Patapsco Marsh, May
29; Pennsylvania, State College, May 30, Wayne, June 1, and Erie, June
2; New Jersey, Cape May County, May 23, Elizabeth, May 30, and Camden,
June 1; New York, Canandaigua, June 7, Geneva, June 9, Orient, June
10, and New York City, June 14; Connecticut, New Haven, June 1, and
Fairfield, June 8; Massachusetts, Lynn, June 5, Harvard, June 9; and
Dennis, June 10; Maine, Portland, June 3; Louisiana, Lobdell, May 18;
Missouri, St. Joseph, May 13, and Corning, May 18; Illinois, Chicago,
May 29, Morgan Park, May 30, and Rantoul, June 2; Indiana, Lake County,
May 27; Ohio, Columbus, May 28, Oberlin, May 29, and Lakeside, June 2;
Michigan, Detroit, May 30, Sault Ste. Marie, May 31; Ontario, Ottawa,
May 31, Hamilton, June 3, and Toronto, June 6; Iowa, Emmetsburg,
May 20, and Sioux City, May 30; Wisconsin, Shiocton, May 28, and
Madison, May 30; Minnesota, Lanesboro, May 23, Hallock, May 29, and
Minneapolis, June 4; Texas, Corpus Christi, May 18; Kansas, Lawrence,
May 18; Nebraska, Lincoln, May 20; South Dakota, Vermilion, May 19,
Dell Rapids, May 22; and Forestburg, May 27; Manitoba, Lake Winnipeg,
June 7, and Shoal Lake, June 12; Lower California, San Geronimo Island,
April 13, Cerros Island, April 17, and Gardeners Lagoon, April 24;
California, San Diego, April 23, Alameda, May 14, Fresno, May 15,
and Santa Barbara, May 22; Washington, Tacoma, May 18; and British
Columbia, Indian Cove, May 29.