Family XLV. COLYMBINAE. DIVERS AND GREBES. GENUS I. COLYMBUS, Linn. DIVER. |
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Family |
THE RED-THROATED DIVER. [Red-throated Loon.] |
Genus | COLYMBUS SEPTENTRIONALIS, Linn. [Gavia stellata.] |
Whilst the icicles are yet hanging from the rocks of our eastern shores, and the snows are gradually giving way under the influence of the April rains,
the Blue-bird is heard to sound the first notes of his love-song, and the
Red-throated Diver is seen to commence his flight. Already paired, the male and
female, side by side, move swiftly through the air, steering their course, at a
great height, towards some far distant region of the dreary north. Pair after
pair advance at intervals during the whole day, and perhaps continue their
journey all night. Their long necks are extended, their feet stretched out
rudder-like beyond the short tail, and onwards they speed, beating the air with
great regularity. Now they traverse a great arm of the sea, now cross a
peninsula; but let what may intervene, their undeviating course holds straight
forwards, as the needle points to its pole. High as they are, you can perceive
the brilliant white of their lower parts. Onward they speed in silence, and as
I stand gazing after them, they have already disappeared from my view.
The middle of May has arrived; our woods are once more filled with the
melodies of numberless warblers, and the Divers have ceased to be seen on our
eastern coasts. To study their habits at this season, we must follow them to
the islands in the mouth of the broad St. Lawrence, or to the granitic rocks of
Labrador. The voyage cannot be performed without great expense, and may be
attended with danger, but enthusiasm urges me on, and now my bark skims over the
blue waters. At length arrived on the rocky shores, I prepare to visit the
interior of that rude and moss-clad region. Thousands of little lakes are seen,
on which are numberless islets richly clad with grass and sedge, the whole of
which seems as if it had grown in a day, so tender are the fresh blades, and so
pure their light green tint. High over these waters, the produce of the melted
snows, the Red-throated Diver is seen gambolling by the side of his mate. The
males emit their love-notes, and, with necks gracefully curved downwards, speed
by the females, saluting them with mellow tones as they pass. In broad circles
they wheel their giddy flight, and now, with fantastic glidings and curves, they
dive towards the spot of their choice. Alighted on the water, how gracefully
they swim, how sportively they beat it with their strong pinions, how quickly
they plunge and rise again, and how joyously do they manifest to each other the
depth and intensity of their affection! Now with erected neck and body deeply
immersed they swim side by side. Reynard they perceive cunningly advancing at a
distance; but they are too vigilant for him, and down like a flash they go, nor
rise again until far beyond his reach. Methinks I see them curiously concealed
among the rank weeds under the bank of their own islet, their bills alone raised
above the water, and there will they remain for an hour, rather than shew
themselves to their insidious enemy, who, disappointed, leaves them to pursue
their avocations.
The Red-throated Diver is found, in tolerable abundance, on the sea-coast
of the United States during autumn, winter, and early spring, from Maryland to
the extremities of Maine. The younger the birds, the farther south do they
proceed to spend the winter, and it is rare to see an old bird, of either sex,
at any season to the south of the Bay of Boston. Farther eastward they become
more common, and they may be said to be plentiful towards the entrance of the
Bay of Fundy, in the vicinity of which a few remain and breed. I found some in
December, January, and February at Boston, where I procured males, females, and
young birds. The old had the red patch on the throat rather darker than in the
breeding season; the delicate grey and white lines on the neck were as pure as I
observed them to be during summer in Labrador; and I have since been convinced
that birds of this family undergo very little if any change of colouring after
they have once acquired their perfect plumage, the Loon and the Black-throated
Diver being included in this remark; while, on the contrary, all the Grebes with
which I am acquainted, lose the beauty of their plumage as soon as the breeding
season is over. This remarkable difference between the Divers and the Grebes
would of itself be sufficient to separate the two genera, were there not also
other distinctions. The Divers, moreover, live on the sea during the greater
part of the year, and resort to ponds, lakes, or the borders of rivers to breed;
whilst the Grebes spend most of their time on inland lakes, marshes, and
streams. Immediately after the breeding season, as soon as the young are able
to fly, the families of Divers make their way to the arms and inlets of the sea,
rarely entering the fresh waters until the following spring.
The Red-throated Diver is at all times an extremely shy and vigilant bird,
ever on the alert to elude its numerous enemies. The sight of man seems
invariably to alarm it, even in the wildest countries in which it breeds. I
have often observed that, while yet several hundred yards from them, they marked
my approach with great watchfulness. First they would dive and make their way
to the further end of the pond, after which, with outstretched necks, they would
remain silent and motionless, until I approached within about a hundred yards,
when, instead of diving again, as the Loon always does, they at once, with a
single spring, rose from the water, and ere I had proceeded a few yards, they
were already eight or ten feet above it. If I crept towards them through the
tangled mosses or shrubs, they would swim about with their heads elevated, as if
determined to make their escape on the appearance of imminent danger. In many
instances, my party observed this species in small flocks of five or six in the
same lake, when it happened to be of considerable extent; and as this was during
the height of the breeding season, we concluded that these associated birds were
barren, as I ascertained that males and females, when once paired, remain
together until their young are able to fly, when they part company, until the
next pairing season, which is about the first of March.
This species begins to breed in Labrador in the beginning of June, and
about a fortnight earlier along the Bay of Fundy. The numerous nests which our
party found in the former district were all placed on small sequestered islands
in the middle of lakes or large ponds of fresh water, rarely more than one mile
distant from the sea-shore. These nests consisted merely of a few blades of
rank grasses loosely put together, and were quite flat, without any down to warm
or conceal the eggs at any period of incubation. The nest was placed within a
few feet of the water, and well-beaten tracks, such as are made by otters, led
to it. Whenever the birds went to this spot they walked nearly erect in an
awkward manner, but when they sat in their nest they laid themselves flat on the
eggs, in the manner of a Goose or Duck. In no instance did they alight on the
islands, but always on the water, at some distance, when, after examining all
around them for awhile, they crawled silently out, and moved to the spot which
contained their treasure.
Having been told that the Red-throated Diver covers its eggs with down in
the manner of many Ducks, I was surprised to find the assertion incorrect, and
having killed several individuals during the period of incubation and
immediately after it, I carefully examined them, and found all of them fully
covered with down, they being, in this respect, quite different from the Eider
Duck, the Velvet Duck, the Harlequin Duck, and other species of that family, nay
even from the Black Guillemot. Probably it is on account of those birds
breeding much farther north, that, according to Dr. RICHARDSON, they there line
their nest with down. We also found the Colymbus glacialis incubating without
any in its nest. The idea generally entertained that this species never lays
more than two eggs I found equally incorrect, for of five nests, two contained
two eggs each, two had three each, and the fifth had three young birds. The
eggs measure 3 inches in length by 1 3/4 in breadth, and are of an elongated
elliptical form, nearly equally rounded at both ends; they are of a deep
olive-brown colour, irregularly marked with spots of a darker dull brown. The
male incubates as well as the female, and both are extremely solicitous about
the safety of their young, which betake themselves to the water on the day
succeeding that of their escape from the egg, and are from the first most expert
swimmers and divers. Two of the young were shot by Captain EMERY, having been
easily approached in the absence of their parents, at which he had shot without
success, they not having yet learned from experience the danger of the proximity
of man. They dived beautifully, and swam with great buoyancy, inclining their
necks forwards, in the manner of the old birds. This was on the 5th of July,
1833. On the 15th of the same month, THOMAS LINCOLN and my son JOHN WOODHOUSE,
saw several young ones, which, although quite small, were equally expert at
diving. When swimming by the side of their mother they floated high, with the
neck quite erect, while the old bird swam deep, with her neck inclined forward.
When the little ones dived, they moved under the water like so many turtles, and
at last were caught on the bottom of the pond, which was small and shallow, by
placing the gun-rods upon them. So averse from moving are the old birds when
sitting on their eggs, that they will not bestir themselves until in imminent
danger, on which, however, they scramble to the water, dive, and, on emerging,
immediately rise on wing without tittering any note. The male only is noisy on
such occasions, and more especially when it returns from afar to its mate, when
it evinces its satisfaction by calling aloud, as it repeatedly passes and
repasses over the spot, and then alights in a pompous manner on the water.
The sexes differ materially in size, the male birds being much larger than
the females, and weighing at an average fully a pound more. These birds are
extremely tenacious of life. One which my son shot on the wing fell, dived
instantly, and swam to a considerable distance under water, but returned to the
surface, back downwards, and quite dead.
The notes of the Red-throated Diver are harsh and rather loud; they
resemble the syllables cac, cac, cac, carah, carah, enounced in rapid
succession. In some instances the young men of my party found that the most
successful method of approaching these birds whilst on the water, was to run as
fast as possible towards them and shout loudly, for on such occasions the birds
dived instead of flying at once, and on emerging again, afforded them much
better chances as they took to wing. At certain times, when approached while
they have young, they utter a soft plaintive note, which evidently conveys to
their offspring their wish that they should remain quiet in their hiding-places.
The Red-throated Diver does not acquire the full beauty of its plumage
until its fourth year. The young are at first covered with thick hairy down, of
a blackish colour, inclining to brown. Before they are fully able to fly, this
is changed into a dull grey on the upper parts, thickly sprinkled with white
dots on the extremity of each feather, the lower parts being of a sullied white.
During the second year these tints are firmer, there are fewer spots above, and
the texture of the lower parts is more silky. In the third, both sexes assume
the fine grey of the hind neck, with its longitudinal white stripes, and here
and there a few spots of red on the lower part of the throat. The next spring
their plumage is perfect.
I have never observed any of these birds on our inland lakes or rivers. In
the neighbourhood of Boston, and along the Bay of Fundy, they are best known by
the names of "Scape-grace" and "Cape-racer." By the 9th of August the young
birds had left the fresh-water lakes and ponds for the bays on the coast, and we
were informed by the settlers, both in Newfoundland and Labrador, that, by the
last days of September, none were to be found in those countries.
The dislike which this species shews to fresh-water after the breeding
season is such, that they are rarely seen in the upper part of large bays, but
prefer for their winter residence the shores of sea-islands and barren rocks.
Thus, at that season, they are met with about the outer islands of the Bay of
Fundy, and those along our eastern coast.
While in fresh water, the Red-throated Diver feeds principally on small
fish, shrimps, leeches, snails, and aquatic insects. The masses of feather-like
substances often found in the stomachs of Grebes, I have never met with in this
species. Its flesh is oily, tough, dark coloured, and disagreeable to the
taste, although I saw some mountain Indians feeding upon it at Labrador with
apparent pleasure.
COLYMBUS SEPTENTRIONALIS, Bonap. Syn., p. 421.
RED-THROATED DIVER, Colymbus septentrionalis, Swains. and Rich. F. Bor. Amer., vol. ii. p. 476.
RED-THROATED DIVER, Nutt. Man., vol. ii. p. 519.
RED-THROATED DIVER, Columbus septentrionalis, Aud. Orn. Biog., vol. iii.p. 20; vol. v. p. 625.
Male, 19, 25. Female, 18, 24.
Not uncommon during winter, autumn, and early spring, from Maryland
eastward. Breeds in Newfoundland, Labrador, and as far north as the Arctic
Seas.
Adult Male, in summer.
Bill as long as the head, slender but strong, straight, rather compressed,
tapering to a point. Upper mandible with the dorsal line almost straight, the
ridge convex, as are the sides, the edges sharp and involute; nasal groove
basal, short; nostrils basal, lateral, direct, oblong, pervious. Lower mandible
with the angle extremely narrow and extending beyond the middle, the dorsal line
straight and sloping upwards to the point, the ridge convex, but narrower than
that of the upper mandible, the edges sharp and involute; the point of both
mandibles rather sharp.
Head of moderate size, oblong, narrowed before. Neck rather long and
slender. Eyes rather small. Body elongated, somewhat depressed. Wings small.
Feet short, rather large, placed very far back; tibia almost entirely concealed;
tarsus short, exceedingly compressed, sharp-edged before and behind, covered all
over with reticulated angular scales; hind toe extremely small, connected with
the second by a very small membrane; the anterior toes united by reticulated
membranes, the fourth longest, the third a little shorter, the second
considerably shorter than the third; all covered anteriorly with very narrow
transverse scutella, the second toe with a free two-lobed membrane; claws very
small, depressed, rounded.
Plumage short and dense; of the head and neck very short, blended; of the
lower parts blended, short, and with a silky gloss; of the upper slightly
glossed and somewhat compact; the feathers in general oblong and rounded. Wings
proportionally very small and narrow, curved; primaries strong, tapering, first
longest, second almost as long, the rest rapidly graduated; secondaries broad,
rounded. Tail extremely short, rounded, of twenty rounded feathers.
Bill bluish-black. Iris deep bright red. Feet brownish-black, the
anterior edge of the tarsus, the upper surface of the toes, the claws, and part
of the webs, pale livid flesh-colour. Fore part and sides of the head, throat,
and sides of the neck, of a fine bluish-grey; fore part of the neck rich
brownish-red; hind part of the head and hind neck longitudinally streaked with
greenish-black and pure white, each feather black in the middle, with the sides
white, the colours disposed in lines. The upper surface brownish-black, tinged
with green, more or less mottled with white according to age, excepting the
primary quills and the tail-feathers, the latter of which are merely paler at
the end. The whole under surface pure white, excepting the feathers on the
sides under the wings, some of those about the vent, and the lower tail-coverts,
which are greyish-brown, with white margins and tips.
Length to end of tail 25 1/2 inches, to end of claws 27; extent of wings
43 1/12; bill 2 2/12; gap 3 3/8; tarsus 3; fourth toe and claw 3 3/4; wing from
flexure 11 3/4; tail 3. Weight 4 lbs.
Adult Female in summer.
The female is precisely similar to the male in form and colouring, but is
considerably smaller.
Length to end of tail 25 inches, to end of claws 28 1/12; extent of wings
43. Weight 3 lbs.
Male in winter immature.
In this state the principal differences are the following:--The fore part
of the neck, instead of being of a uniform rich brownish-red, is merely mottled
with that colour; all the feathers of the upper surface have each two white
spots towards the end; the tail-feathers are edged and terminated with white;
the colouring in general is somewhat less pure and deep, and the bill is of a
much paler tint.
Young bird unfledged.
The young are at first covered with a dense elastic down of a greyish-black
colour, tinged with brown. The bill is bluish-black, its basal edges yellow;
the iris reddish-brown.
The width of the mouth is 10 twelfths; but the lower jaw is dilatable to
1 1/2 inches. On the palate are two papillate ridges, with two series of
papillae on each side of the posterior aperture of the nares, which is
oblongo-linear, 1 1/4 inches long, and margined with papillae. On the anterior
part of the upper mandible are three ridges. The tongue is 1 inch 8 twelfths
long, very slender, trigonal, flat above, tapering to a horny point.
OEsophagus, Fig. 1 [a b c],
14 inches in length, at its commencement 1 1/2 inches in
width, but at the lower part of the neck enlarging to 2 inches; on entering the
thorax it contracts to 1 1/2 inches; the proventriculus, [b c], again enlarges
to 2 inches, forming a very large ovate sac. The lobes of the liver are very
large and nearly equal, the length of the one being 3 inches 10 twelfths, that
of the other 3 inches 8 twelfths. The stomach, [c d e f], is rather large,
roundish, 1 inch 9 twelfths in diameter, a little compressed, its lateral
muscles rather thin, the lower somewhat prominent. Its contents are remains of
fishes, and a great quantity of small stones and pebbles. The epithelium is
pretty thick, dense, with numerous longitudinal rugae. The proventricular
glands form a belt 1 inch 10 twelfths in breadth. The intestine is 4 feet 11
inches long; its average width 8 twelfths. The coeca, Fig. 2, [c c], 2 1/2
inches long, 4 1/2 twelfths broad, towards the end 6 twelfths, with the
extremity rounded. The rectum is 2 inches long, with a globular cloaca, [b],
1 1/2 inches in diameter.
Trachea 11 1/2 inches long, much flattened, from 6 twelfths to 4 twelfths
in breadth; the rings 145, with 2 dimidiate. Bronchi moderate, of 20 half
rings. Lateral muscles strong; a single series of inferior laryngeal muscles
going to the last half ring of the trachea.
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