Family XLIII. PROCELLARINAE. FULMARS. GENUS I. LESTRIS, Illiger. JAGER. |
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Family |
THE POMARINE JAGER. [Pomarine Jaeger.] |
Genus | LESTRIS POMARINUS, Temm. [Stercorarius pomarinus.] |
This bird I never had an opportunity of examining until I visited Labrador;
nor am I able to give you much information respecting its habits as obtained by
my own observation, and therefore I shall take the liberty of adding to my
description such notices as I may judge interesting, taken from the works of
authors who, having seen for themselves, are entitled to credit.
While sailing towards the harbour of Little Macatina, and yet about forty
miles distant from it, although not far from the shore, we observed a bird of
this species approaching the vessel. It flew in the manner of the Pigeon Hawk,
to my account of which I may refer you, alighted on the water like a Gull, and
fed on some codfish's liver that had been thrown overboard for the purpose of
attracting it. Several small Petrels joined it, but it did not come within
shot, and the sea was too rough for even our whale-boat. On the 30th of July
the young men of my party brought me a fine adult female, in excellent order,
from which I drew the figure in the plate. A few days after we experienced a
very heavy gale while in the harbour of Bras d'Or, during the continuance of
which twenty or thirty of these birds came about us, although none of them
approached within shot, and no boat could have ridden the furious waves without
imminent danger. On that occasion, however, I was enabled to observe some of
their habits. They flew wildly about, yet with much grace, moving rapidly to
and fro, now struggling against the blast, now bearing off and drifting to a
considerable distance. Many Gulls were flying about, having also made for the
harbour to obtain some shelter from the storm. The Lestris chased the smaller
species with effect, but never approached the Great Black-backed Gulls, nor even
their young, which were also flying with the rest. The Kittiwakes and the
Ring-billed Gulls were the species which we saw them attack, although they did
not procure much food from them, the weather being such that they could not
fish. They were therefore contented, as was the Lestris, with the fishes that
had been thrown on shore. At times the Jagers would ramble over the land,
flying close upon the rocks, and proceeding at a rapid rate even against the
wind. They remained in our neighbourhood until the tempest abated, when they
went off to sea, and I saw no more of them until we reached St. George's Bay in
Newfoundland.
There, on a squally afternoon, two or three of them were observed flying
around, but keeping at such a distance that we could not shoot any of them. The
following day, after setting sail, we encountered a heavy gale, which, although
foretold by me from the appearance of the birds in the harbour, our good captain
would not believe as likely to happen. We were obliged to lie-to, and were
tossed about for three nights and days, but escaped with little other damage
than the loss of a pet Gull, which was washed overboard.
On our return to Eastport, Captain EMERY told me that he had seen a great
number of these Jagers near Cape Sable; and at Halifax, in Nova Scotia, I was
assured that they breed on Sable Island, which is sixty or seventy miles distant
from the coast. I never observed one of these birds along the shores of the
United States, although some of the genus go as far south in winter as the Gulf
of Mexico.
Nothing is known with certainty respecting the changes which this species
undergoes as it advances toward maturity. Captain JAMES CLARK Ross, R. N., has
informed me that a nest containing two eggs was found by him near Fury Point,
close by the edge of a small lake. I have no doubt that this bird breeds in
Labrador, as the female which I obtained in July appeared as if it had young at
the time.
My friend Mr. SELBY states that he is not aware that an adult bird has yet
been killed in Britain. M. TEMMINCK says it forms a rude nest of grass and
moss, which is placed on a tuft in the marshes, or on a rock, and lays two or
three very pointed eggs, of a greyish-olive colour, marked with a few blackish
spots. Dr. RICHARDSON has the following notice respecting it in the Fauna
Boreali-Americana:--"The Pomarine Jager or Gull-hunter is not uncommon in the
Arctic seas and northern outlets of Hudson's Bay, where it subsists on putrid
fish and other animal substances thrown up by the sea, and also on the matters
which the Gulls disgorge when pursued by it. It retires from the north in the
winter, and makes its first appearance at Hudson's Bay in May, coming in from
seaward."
LESTRIS POMARINA, Bonap. Syn., p. 364.
LESTRIS POMARINA, Pomarine Jager, Swains. and Rich. F. Bor. Amer.,vol. ii. p. 429.
POMARINE JAGER, Nutt. Man., vol. ii. p. 315.
POMARINE JAGER, Lestris pomarinus, Aud. Orn. Biog., vol. iii. p. 396;vol. v. p. 643.
Female, 20 1/4, 48.
From Massachusetts northward. Seen in Labrador. Breeds in high northern
latitudes.
Adult Female.
Bill shorter than the head, strong, slightly compressed, straight, the tip
curved. Upper mandible with the dorsal line nearly straight, toward the tip
curved, the ridge broad and convex with a slight central depression, the sides
convex, the edges sharp and inflected, the tip compressed, rather rounded but
sharp. Nasal groove long, narrow, curved; nostrils in its fore part, medial,
lateral, longitudinal, broad before, extremely narrow behind, open and pervious.
Lower mandible with the angle long and narrow, a slight prominence at its
extremity, beyond which the dorsal line is slightly concave, the sides erect,
and slightly convex, the edges sharp and inflected, the tip obliquely truncate.
Head rather large. Neck of moderate length. Body rather full. Feet of
moderate length, rather slender; tibia bare at its lower part, and rough all
round with small convex scales; tarsus compressed behind, anteriorly covered
with decurved scutella, the sides reticulated, the hind part rough with small
pointed scales; hind toe extremely small and elevated, the fore toes of moderate
size, connected by reticulated webs, which have their margins convex; the third
toe longest, the fourth nearly as long, all scutellate above. Claws strong,
curved, very acute, compressed, that of third toe with a sharp inner edge.
The plumage in general is close, elastic, soft and blended; the feathers on
the back and wings rather compact and distinct. Wings very long, rather broad,
pointed; primary quills tapering and rounded, the first longest, the rest
rapidly graduated; secondary rather short, rounded. Tail of moderate length,
the feathers, which are twelve, are broad and rounded, the two middle an inch
longer than the next.
Bill blackish-brown at the end, dingy-yellow towards the base. Iris brown.
Tibia, toes, webs, and lower half of tarsus black, the upper half light blue;
claws black. Upper part and sides of the head anteriorly brownish-black; upper
part of neck all round yellowish-white; the rest of the neck white, barred with
brownish-black, each feather having two transverse bands of that colour; breast
white; sides, abdomen and lower tail-coverts white, barred with brownish-black,
as are the upper tail-coverts. Back and wings brownish-black; primary quills of
the same colour, white on the inner webs towards the base, as are the
secondaries and tail-feathers, lower surface of wings mottled and barred with
white and dusky.
Length to end of tail 20 1/4 inches, to end of wings 20 1/4, to end of
claws 19 1/4; extent of wings 48; wing from flexure 14; tail 6 2/12; bill along
the back 1 9/12, along the edge of lower mandible 2 1/2; tarsus 2 1/12; middle
toe 1 9/12, its claw 8/12. Weight 1 1/2 lbs.
Female, from Dr. T. M. BREWER. The mouth rather wide, 1 inch 2 twelfths
across; the palate flat, with two longitudinal papillate ridges, the space
between which and the palatal slit is also covered with papillae; anteriorly, on
the mandible, are three ridges; posterior aperture of the nares oblongo-linear,
with its margins papillate; the lower mandible dilatable, as in the Gulls.
Tongue 1 inch long, emarginate and papillate at the base, broadly channelled
above, contracted and induplicate toward the end, horny beneath, and thin-edged,
with the point slit to the depth of 1 1/2 twelfths. Lobes of the liver very
unequal, the right 2 1/4 inches long, the left 1 inch 10 twelfths; gall-bladder
oblong, 7 1/2 twelfths long, 3 twelfths broad. The stomach, Fig. 1 [c d], is small,
1 inch 2 twelfths long, 1 inch in breadth; its lateral muscles thin; the
epithelium thin, longitudinally rugous, of a reddish colour. The proventricular
glands extremely small, roundish, forming a belt 7 twelfths in width.
Intestine, [f g h l m], 24 1/2 inches long, 6 twelfths wide at the top,
but contracting to 4 twelfths; it forms 7 curves; the coeca, [j k], 1 inch 10
twelfths in breadth. Trachea 5 inches long, from 3 1/2 twelfths to 2 1/2
twelfths long, for 8 twelfths their width is 1 twelfth, afterwards 2 1/2
twelfths, diminishing to 1 3/4 twelfths, the extremity blunt; rectum 2 inches 3
twelfths long, for 1 inch 4 twelfths in width, then enlarging into an oblong
cloaca 10 twelfths in breadth; considerably flattened; the rings 98, unossified,
of the same structure as in the Gulls. Bronchi rather wide, of 20 half rings.
Muscles as in the Gulls.
The digestive organs of this bird differ from those of the Gulls only in
having the coeca much more elongated; the cloaca oblong, instead of being
globular, and the stomach less muscular. The tongue differs greatly from that
of either the Gulls or Terns.
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