(_Colymbus nigricollis californicus._)
The American Eared Grebe belongs to the order of Diving Birds
(Podicipedes) and the family of Grebes (Podicipidae). The order also
includes the loons and auks, having in all about thirty-six species
that frequent North America. Closely related to the loons, the Grebes
differ from them in having the head incompletely feathered near the
nostrils, which are not lobed. The feet also are not completely webbed,
as are those of the loons.
Owing to the inadequately developed wings, the Grebes are poorly
provided with means for protracted flight. Locomotion on land is
equally difficult, due to their short legs and the fact that they are
inserted far back on the body, necessitating a partially erect position
in walking. However, they are expert swimmers and divers and will, when
alarmed, sink quietly back into the water, swimming long distances
with only the bill above the surface of the water. The popular name
"Hell-diver," by which these birds are frequently known, has reference
to the rapidity with which they dive.
The apparent lack of a tail and the ruffs, frequently composed of
variously colored feathers, give the grebes a peculiarly characteristic
appearance. The plumage of the breeding season differs greatly from
that of the adult in winter and that of the young.
The grebes are abundant throughout the world, seemingly preferring
lakes and rivers as a foraging ground rather than the seacoast.
The American Eared Grebe has an extensive range, including that part
of North America west of the Mississippi Valley and from the Great
Slave Lake south to Guatemala. It breeds in nearly all parts of this
territory.
A few years since Professor Henshaw published in the American
Naturalist some very interesting facts concerning the nesting habits
of this bird, and they especially well illustrate some of its
characteristics. He says, "In a series of alkali lakes, about thirty
miles northward of Fort Garland, Southern Colorado, I found this
species common and breeding. A colony of perhaps a dozen pairs had
established themselves in a small pond four or five acres in extent. In
the middle of this, in a bed of reeds, were found upwards of a dozen
nests. These in each case merely consisted of a slightly hollowed pile
of decaying weeds and rushes, four or five inches in diameter, and
scarcely raised above the surface of the water upon which they floated.
In a number of instances they were but a few feet distant from the
nests of the coot (Fulica Americana) which abounded. Every Grebe's nest
discovered contained three eggs, which in most instances were fresh,
but in some nests were considerably advanced. These vary but little in
shape, are considerably elongated, one end being slightly more pointed
than the other. The color is a faint yellowish or bluish white, usually
much stained from contact with the nest. The texture is generally quite
smooth, in some instances roughened by a chalky deposit. The eggs were
wholly concealed from view by a pile of weeds and other vegetable
material laid across. That they were thus carefully covered merely for
concealment I cannot think, since, in the isolated position in which
the nests are usually found, the bird has no enemy against which such
precaution would avail. On first approaching the locality, the Grebes
all congregated at the further end of the pond, and shortly betook
themselves through an opening to the neighboring slough; nor, so far
as I could ascertain, did they again approach the nests during my stay
of three days. Is it not, then, possible that they are more or less
dependent for the hatching of their eggs upon artificial heat induced
by the decaying vegetable substances of which the nests are wholly
composed?"
The food of the Grebe consists of fish to a great extent, which are
dexterously caught while swimming under water. They also feed upon
the insects floating upon the surface, and will, when other food is
lacking, feed upon mollusks.
[Illustration: AMERICAN EARED GREBE.
(Colymbus nigricollis californicus.)
1/2 Life-size.
FROM COL CHI. ACAD. SCIENCES.
COPYRIGHT 1900, BY
A. W. MUMFORD, CHICAGO.]