_Lanius excubitoroides_, SWAINSON, F. B. A. II, 1831, 115
(Saskatchewan).—GAMBEL, Pr. A. N. Sc. 1847, 200 (Cala.).—CASSIN,
Pr. A. N. Sc. 1857, 213.—SCLATER, P. Z. S. 1864, 173 (City of
Mexico). _Collyrio excubitoroides_, BAIRD, Birds N. Am. 1858, 327.
_Collurio excub._ BAIRD, Rev. Am. B. 1864, 445.—COOPER, Orn. Cal.
I, 1870, 138. _? Lanius mexicanus_, BREHM, Cab. Jour. II, 1854,
145.—SCLATER, Catal. 1861, 46 (Mexico). _Lanius ludovicianus_,
MAX. Cab. Jour. 1858, 191 (Upper Missouri).—DRESSER & SHARPE, P.
Z. S. 1870, 595.
HAB. Western Province of North America, as far north as Oregon; Middle
North America, to the Saskatchewan, and east to Wisconsin, Michigan,
and Illinois; south to Orizaba and Oaxaca, and City of Mexico; Cape
St. Lucas.
The precise boundaries between this species and _C. ludovicianus_ are
difficult of definition, as the transition is almost insensible.
The young bird is pale fulvous-ash above, everywhere with transverse
crescentic bars of dusky. Two bands of mottled pale fulvous across
wings, on tips of middle and greater coverts. Tail tipped with
ochraceous, the white feathers tinged with the same. Breast and sides
with obsolete bars of dusky. Black band on side of head rather
obsolete.
In its extreme stage of coloration it differs from _ludovicianus_ in
paler and purer color; the ash of back lighter; the under parts
brilliant white, not decidedly plumbeous on the sides as in the other,
and without so great a tendency to the usual obsolete waved lines
(noticed distinctly only in winter or immature birds); the axillars
bluish-white, not plumbeous. The white of wings and tail is more
extended; the hoary of forehead and whitish of scapulars more
distinct. The bristles at base of bill somewhat involving the feathers
are black, forming a narrow frontal line, not seen in the other. The
most striking difference is in the rump and upper tail-coverts, which
are always appreciably and abruptly lighter than the back, sometimes
white or only faintly glossed with plumbeous; while in typical
specimens of _ludovicianus_ these feathers are scarcely lighter at
all, and generally more or less varied with blackish spots at the end.
The legs and tail are apparently longer, the latter less graduated.
These differences are, however, most appreciable in specimens from the
Middle and Western Provinces. Those from the Western States, east of
the Missouri River, as far north as Wisconsin, are more intermediate
between the two, although still nearest to the Rocky Mountain bird as
described; the back darker, the rump and axillars more plumbeous, the
sides more bluish. There is little doubt that the examination of
series from the States along the Mississippi will show a still closer
resemblance to typical _C. ludovicianus_, and that the gradation
between the two extremes will be found to be continuous and unbroken.
It therefore seems reasonable to consider them all as one species,
varying with longitude and region according to the usual law,—the more
western the lighter, with longer tail. The only alternative is to
suppose that two species, originally distinct, have hybridized along
the line of junction of their respective provinces, as is certainly
sometimes the case. The approximation in many respects of coloration
of the Shrikes of the Pacific coast to those of the South Atlantic
States is not without its importance in the discussion of the subject.
However it may be, it is necessary to retain the name of
_excubitoroides_, as representing, whether as species or variety, a
peculiar regional form, which must be kept distinctly in mind. The
comparatively greater size of the bill in the Cape St. Lucas specimens
is seen in other species from this locality (No. 26,438 of adjacent
figure).
[Line drawings: 26438
13600]
The intensity of the black front in this species varies considerably,
being sometimes very distinct, and again entirely wanting. This may
probably be a character of the breeding-season, the dulness of black
anterior to the eye and the lighter color of the bill having a close
relationship here, as in other species, to maturity, sex, and season.
HABITS. This variety was first described from specimens obtained in
the territory of the Hudson’s Bay Co. Richardson states that it was
not found farther north than the fifty-fourth degree, and there only
in the warm and sandy plain of the Saskatchewan. Its manners, he says,
are precisely similar to those of the _borealis_, feeding chiefly on
the grasshoppers, which were very numerous on the plains. Mr. Drummond
found its nest in the beginning of June, in a bush of willows. It was
built of the twigs of the _Artemisia_ and dry grass, and lined with
feathers. The eggs were six in number, of a pale yellowish-gray color,
with many irregular and confluent spots of oil-green, mixed with a few
of smoke-gray.
Mr. Ridgway met with it, in his Western explorations, in all
localities, but most frequently among the _Artemisia_ and in the
meadow-tracts of the river valleys. It is also seen on all parts of
the mountains, among the cedar groves, localities in which the
_ludovicianus_ is said never to be found.
Dr. Cooper describes this bird as abundant in all the plains-region of
California, but not as far as the Columbia River. South of latitude
38°, they reside all the year. They were abundant about Fort Mohave
all winter, and nested as early as the 19th of March in a thorn-bush.
They had young early in April. At San Diego they nested later, about
April 20. He speaks of their singing as an attempt at a song, the
notes being harsh, like those of a Jay, but not imitative. They catch
birds, but do so very rarely, depending upon grasshoppers and other
insects.
The nests of the _excubitoroides_, so far as I have had any
opportunity to examine them, always exhibit a very marked contrast, in
the elaborateness of their structure, to any of the _ludovicianus_
that have fallen under my notice. They resemble those of the
_borealis_ in their size and the felted nature of their walls, but are
more coarsely and rudely put together. They have an external diameter
of about eight inches, and a height of four. The cavity is also large
and deep. These nests are always constructed with much artistic skill
and pains. The base is usually a closely impacted mass of fine
grasses, lichens, mosses, and leaves, intermingled with stout dry
twigs. Upon this is wrought a strong fabric of fine wood-mosses,
flaxen fibres of plants, leaves, grasses, fur of quadrupeds, and other
substances. Intertwined with these are a sufficient number of slender
twigs and stems of plants to give to the whole a remarkable strength
and firmness. This is often still further strengthened by an external
protection woven of stouter twigs and small ends of branches, stems,
etc. The whole is then thoroughly and warmly lined with a soft matting
of the fur of several kinds of small animals, vegetable down, and a
few feathers.
The eggs, five or six in number, measure 1.00 by .73 of an inch, and
strongly resemble those of both the _borealis_ and the _ludovicianus_.
Their ground-color is pale greenish-white, over which are marks and
blotches, more or less confluent, of lilac, purplish-brown, and light
umber.
Mr. Ridgway, who is familiar with this bird in Southern Illinois,
informs me that in that section it is a resident species, being
abundant during the summer and by no means rare in the winter. It is
there, strangely enough, often called the Mocking-Bird, its similar
appearance and fondness for the same locality leading some persons to
confound these very different birds. In districts where the true
_Mimus_ is not common, young birds of this species are frequently
taken from their nests and innocently sold to unsuspecting admirers of
that highly appreciated songster.
This bird inhabits, almost exclusively, open situations, being
particularly fond of waste fields where young honey-locusts
(_Gleditschia triacanthos_) have grown up. Among their thorny branches
its nests are almost utterly inaccessible, if beyond the reach of
poles. In such localities this bird may often be seen perched in an
upright position upon some thorn-bush, or a fence-stake, quietly
watching for its prey, remaining nearly an hour at a time motionless
except for an occasional movement of the head.
The flight of this bird, Mr. Ridgway adds, is quite peculiar, utterly
unlike that of any other bird except the _Oreoscoptes montanus_, which
it only slightly resembles. In leaving its perch it sinks nearly to
the ground, describing a curve as it descends, and, passing but a few
feet above the surface, ascends in the same manner to the object upon
which it is next to light. The flight is performed in an undulating
manner, the bird sustaining itself a short time by a rapid fluttering
of the wings, and sinking as this motion is suspended. As it flies,
the white patch on the wing, with the general appearance of its gray
and white plumage, increases its resemblance to the Mocking-Bird.
Though very partial to thorn-trees (honey-locust), other trees having
a thick foliage—as those canopied by a tangled mass of wild
grapevines—are frequently occupied as nesting-places; while a pair
frequently make their home in an apple-orchard, selecting the old
untrimmed trees. The situation of the nest varies according to the
character of the tree; if in a thorn-bush, it is placed next the
trunk, encased within protecting bunches of thorns; but if in an
apple-tree, it is situated, generally, near the extremity of a
horizontal branch. The number of eggs is generally six, but Mr.
Ridgway has several times found seven in one nest. No bird is more
intrepid in the defence of its nest than the present one; at such
times it loses, apparently, all fear, and becomes almost frenzied with
anger, alighting so near that one might grasp it, were he quick
enough, and with open mouth and spread wings and tail threatening the
intruder, its attacks accompanied by a peculiar crackling noise,
interrupted by a harsh, grating _qua_, _qua_, _qua_, slowly repeated,
but emphatically uttered.
The habit peculiar to the Shrikes of impaling their victims Mr.
Ridgway has observed frequently in this species; for this purpose the
long and extremely sharp thorns of the honey-locust serve it
admirably; and “spitted” upon them he has found shrews, mice,
grasshoppers, spiders, and even a Chimney-Swallow (_Chætura
pelagica_); and, in another instance, but upon the upright broken-off
twig of a dead weed in a field, a large spider. He has also known this
bird to dart at the cage of a Canary-Bird, and frighten the poor
inmate so that it thrust its head between the wires, when it was
immediately torn off by the powerful beak of the Butcher-Bird.
The young of this species becomes a very pleasing and extremely docile
pet. Mr. Ridgway has known one which, though fully grown, with power
of flight uninjured, and in possession of unrestrained freedom, came
to its possessor at his call, and accompanied him through the fields,
its attachment being rewarded by frequent “doses” of grasshoppers,
caught for it. It had been fully feathered before taken from the nest.
Unfortunately the vocal capabilities of this Shrike are not sufficient
to allow its becoming a general favorite as a pet; for, although
possessing considerable talent for mimicry, it imitates only the
rudest sounds, while its own notes, consisting of a grating, sonorous
_qua_ and a peculiar creaking sound, each with several variations, are
anything but delightful.