_Hirundo bicolor_, VIEILL. Ois. Am. Sept. I, 1807, 61, pl. xxxi.—AUD.
Orn. Biog. I, pl. xcviii.—IB. Birds Am. I, pl.
xlvi.—CASSIN.—BREWER, N. Am. Oöl. I, 1857, 100, pl. iv, fig. 47
(eggs).—LEMBEYE, Aves de Cuba, 1850, 46, lam. vii, fig. 2.—BAIRD,
Birds N. Am. 1858, 310.—LORD, Pr. R. A. Inst. Woolwich, IV, 1864,
15 (Br. Columbia; nesting).—JONES, Bermudas, 34 (Sept. 22,
1849).—COOPER & SUCKLEY, P. R. R. Rep. XII, II, 184.—DALL &
BANNISTER, 279 (Alaska).—SAMUELS, 257.—COOPER, Orn. Cal. 1, 1870,
106. _Petrochelidon bicolor_, SCLATER, P. Z. S. 1857, 201.—IB.
1859, 364 (Xalapa).—SCLATER & SALVIN, Ibis, 1859, 13 (Guatemala).
_Tachycineta bicolor_, CAB. Mus. Hein. 1850, 48; Jour. Orn. 1856,
4 (Cuba).—GUNDLACH, Jour. Orn. 1861, 330 (common in Cuba).
_Hirundo_ (_Tachycineta_) _bicolor_, BAIRD, Rev. Am. B. 1864, 296.
_Hirundo viridis_, WILS. _Hirundo leucogaster_, STEPHENS.
SP. CHAR. Glossy metallic bluish-green above; entirely white beneath.
_Female_ duller in color. Length, 6.25 inches; wing, 5.00; tail, 2.65.
_Young bird_ dull sooty-gray above, much like that of _H. thalassina_;
but may readily be distinguished by the feathers of the throat being
pure white to their roots, instead of having the concealed bases
grayish as in that species.
HAB. Whole United States, and north to Slave Lake, south to Guatemala;
Bermuda; Cuba, common in winter. Breeds on table-lands of Mexico.
[Illustration: _Hirundo bicolor._]
HABITS. This Swallow has quite an extended distribution. Found
throughout North America in the seasons of its migrations, or
breeding, it is only a little less restricted in its area of nesting
than the preceding species. It breeds from latitude 38° to high Arctic
regions, and is also resident throughout the year in the Plateau of
Mexico. It is abundant in winter in the West Indies, in Central
America, and in Northern South America. It is a common bird about
Boston, where it replaces the Purple Martin, and is even more abundant
in the British Provinces. Dr. Cooper also found it a very common
species in the western portions of Washington Territory, where it was
invariably found to breed in hollow trees. In California he states it
to be a more or less constant resident, a few wintering in the
southern portion of the State. He met with it both at San Diego and at
Stockton, in February. He regards them as the hardiest of the
Swallows, preferring the coast and the mountain-tops for their
residence in that State. At Santa Cruz five or six pairs in 1866 were
resident through the winter, where he saw them in January during the
coldest of the season. They roosted in the knot-holes in the houses in
which they had previously raised their young.
This Swallow, in the more thickly settled portions of the country in
which it breeds, exhibits a marked departure in many of its habits
from those observed in wilder regions. In the latter places we find it
a comparatively wild species, avoiding the society of man, and
breeding exclusively in hollow trees and stumps, and deserving the
name by which it is known in the British Provinces, of the “Wood
Swallow.” In the islands of Grand Menan, in 1851, where repeated
attempts had been made to induce these birds to build in martin-boxes,
the endeavor had been entirely unsuccessful. Yet the birds were so
abundant that hardly a hollow tree or stump, on certain of the smaller
islands, could be found, that did not contain a nest of this species.
This is still the case on the Pacific coast, though not exclusively
so. It was not until after the publication of his Ornithological
Biography that Audubon was aware of any departure from this mode of
nesting on the part of this Swallow, although it had not escaped the
notice of Wilson.
In Eastern Massachusetts these birds have undergone an entire change
of habit, breeding there exclusively in martin-boxes, and rarely, if
ever, nesting in hollow trees,—a fact perhaps attributable to the
scarcity of these opportunities along the sea-coast, where this bird
is principally found. In Western Massachusetts, Mr. Allen states them
to be not very common and the least abundant of the Swallows. Any
sheltered and accessible box, however rough it may be, will answer its
purpose, whether the more elaborate martin-house, or a mere candle-box
with an open end. Mr. Audubon has known them to drive away a Barn
Swallow from its nest, and to take possession, but this was probably
exceptional. In one case, two small houses for birds put up in the
same yard were taken possession of by a single pair of Swallows, and
nests built in each; only one, however, of these was made use of.
Whether this freak was the result of indecision or from a grasping
selfishness, it is not possible to conclude, but apparently the
former.
In the rural districts, even on the coast, these birds are not so
abundant as in the cities, as in the latter they are less annoyed by
other birds. The common Robin is often especially aggressive, seeking
to drive them off his assumed premises. In one instance the Robin has
been known to station himself on a platform in front of its nest for
hours, and persistently refuse to permit its visits. Assistance was
sought, and all the Swallows in the neighborhood came to the rescue.
They sailed with angry cries over the head of the offender, at times
darting down upon him as if to strike at him, but accomplishing
nothing. The besieger maintained his ground until the writer
intervened and drove him away, when the Swallows once more took
possession, and fed their hungry nestlings in peace.
This species breeds from about latitude 38° to the extreme northern
regions, and along the Arctic seas, wherever facilities for nesting
are found. Richardson found them breeding in hollow trees on the
Mackenzie River, in latitude 65°. Everywhere on both coasts they are
very common, but are less numerous in the interior. Mr. Dall found it
in Alaska from Fort Yukon to the sea. It was known to the Russians as
the River Swallow. It was also met with in Sitka, by Bischoff. It has
not been observed in Greenland.
During the breeding-season this species is more quarrelsome than any
of its kindred, and is often more than a match for larger birds.
Coming earlier in the season than the Purple Martin, it will often
intrude itself into its premises and maintain possession. They are
devotedly attached to their offspring, and bewail any accidents to
them or any threatened peril. The same pair will return year after
year to the same premises, and they soon become on familiar terms with
the members of a family they frequently meet, so much so as to watch,
when they have received materials for their nests, for a further
supply, and will fly close to the person from whom they receive them.
A pair which had thus, year after year, received supplies of feathers
for their nests from the younger members of the family in whose yard
their nest was built, would almost take them from the hands of their
providers. This pair sat so close as to permit themselves to be taken
from their nest, and when released would at once fly back to their
brood. They build a loose, soft, and warm nest of fine soft leaves and
hay, abundantly lined with down and feathers, with which the eggs are
not unfrequently covered. The addition of soft and warm materials is
often made during incubation, and the nest is thoroughly repaired
before it is used for a second brood, of which they usually have two
in a season.
The eggs are of a uniform pure white, and are never spotted. They have
a delicate pinkish shade before they are blown. They are of an
oblong-oval shape, one end more pointed than the other, and they vary
considerably in size. They vary in length from .75 to .875 of an inch,
and in breadth from .50 to .56.
Mr. Hepburn states that the great mass of these birds leave California
in August, but that a few are resident during the winter. The
principal accession to their numbers takes place about the end of
February, and they become quite abundant by the end of March. In
Vancouver they are a month later. In 1853 Mr. Hepburn states that a
pair constructed their nest in a piece of canvass at the end of the
yard-arm of a store-ship that lay off the levee at Sacramento. He
first noticed them on the 28th of April, when the nest had already
made some progress. By the 19th of May there were seven eggs in it
which were slightly incubated. The nest was a great mass of hay and
dried grasses, in the midst of which was a cup-shaped depression very
neatly lined with feathers, some of which bent over, forming a slight
dome.
Hirundo thalassina, SWAINS.