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- $Unique_ID{BRD00712}
- $Pretitle{}
- $Title{Black Skimmer or Razor-billed Shearwater}
- $Subject{Larinae; Rhynchops; Rynchops; nigra; niger; Black Skimmer; Razor-billed
- Shearwater}
- $Journal{Birds of America: Volume VII}
- $Volume{Vol. 7:67-74}
- $Family{Larinae}
- $Genus{Rhynchops; Rynchops}
- $Species{nigra; niger}
- $Common_Name{Black Skimmer; Razor-billed Shearwater}
- $Log{
- Plate CCCCXXVIII*00712P1.scf
- Family*00710.txt
- Genus*00711.txt
- Figure*0071201.scf}
-
- Portions copyright (c) Creative Multimedia Corp., 1990-91, 1992
-
- B I R D S O F A M E R I C A .
-
- By John James Audubon, F. R. SS. L. & E.
-
- ------------------------------------------
- VOL. VII.
- --------------------------------
-
-
- BLACK SKIMMER OR RAZOR-BILLED SHEARWATER.
- [Black Skimmer.]
-
-
- RHYNCHOPS NIGRA, Linn.
- [Rynchops niger.]
-
-
- PLATE CCCCXXVIII.--MALE.
-
-
- This bird, one of the most singularly endowed by nature, is a constant
- resident on all the sandy and marshy shores of our more southern States, from
- South Carolina to the Sabine river, and doubtless also in Texas, where I found
- it quite abundant in the beginning of spring. At this season parties of Black
- Skimmers extend their movements eastward as far as the sands of Long Island,
- beyond which however I have not seen them. Indeed in Massachusetts and Maine
- this bird is known only to such navigators as have observed it in the southern
- and tropical regions.
- To study its habits therefore, the naturalist must seek the extensive
- sand-bars, estuaries, and mouths of the rivers of our Southern States, and enter
- the sinuous bayous intersecting the broad marshes along their coasts. There,
- during the warm sunshine of the winter days, you will see thousands of Skimmers,
- covered as it were with their gloomy mantles, peaceably lying beside each other,
- and so crowded together as to present to your eye the appearance of an immense
- black pall accidentally spread on the sand. Such times are their hours of rest,
- and I believe of sleep, as, although partially diurnal, and perfectly able to
- discern danger by day, they rarely feed then, unless the weather be cloudy. On
- the same sands, yet apart from them, equal numbers of our Black-headed Gulls may
- be seen enjoying the same comfort in security. Indeed the Skimmers are rarely
- at such times found on sand or gravel banks which are not separated from the
- neighbouring shores by some broad and deep piece of water. I think I can safely
- venture to say that in such places, and at the periods mentioned, I have seen
- not fewer than ten thousand of these birds in a single flock. Should you now
- attempt to approach them, you will find that as soon as you have reached within
- twice the range of your long duck-gun, the crowded Skimmers simultaneously rise
- on their feet, and watch all your movements. If you advance nearer, the whole
- flock suddenly taking to wing, fill the air with their harsh cries, and soon
- reaching a considerable height, range widely around, until, your patience being
- exhausted, you abandon the place. When thus taking to wing in countless
- multitudes, the snowy white of their under parts gladdens your eye, but anon,
- when they all veer through the air, the black of their long wings and upper
- parts produces a remarkable contrast to the blue sky above. Their aerial
- evolutions on such occasions are peculiar and pleasing, as they at times appear
- to be intent on removing to a great distance, then suddenly round to, and once
- more pass almost over you, flying so close together as to appear like a black
- cloud, first ascending, and then rushing down like a torrent. Should they see
- that you are retiring, they wheel a few times close over the ground, and when
- assured that there is no longer any danger, they alight pell-mell, with wings
- extended upwards, but presently closed, and once more huddling together they lie
- down on the ground, to remain until forced off by the tide. When the Skimmers
- repose on the shores of the mainland during high-water, they seldom continue
- long on the same spot, as if they felt doubtful of security; and a person
- watching them at such times might suppose that they were engaged in searching
- for food.
- No sooner has the dusk of evening arrived than the Skimmers begin to
- disperse, rise from their place of rest singly, in pairs, or in parties from
- three or four to eight or ten, apparently according to the degree of hunger they
- feel, and proceed in different directions along parts of the shores previously
- known to them, sometimes going up tide-rivers to a considerable distance. They
- spend the whole night on wing, searching diligently for food. Of this I had
- ample and satisfactory proof when ascending the St. John river in East Florida,
- in the United States schooner Spark. The hoarse cries of the Skimmers never
- ceased more than an hour, so that I could easily know whether they were passing
- upwards or downwards in the dark. And this happened too when I was at least a
- hundred miles from the mouth of the river.
- Being aware, previously to my several visits to the peninsula of the
- Floridas and other parts of our southern coasts where the Razor-bills are
- abundant, of the observations made on this species by M. LESSON, I paid all
- imaginable attention to them, always aided with an excellent glass, in order to
- find whether or not they fed on bivalve shell-fish found in the shallows of
- sand-bars and other places at low water; but not in one single instance did I
- see any such occurrence, and in regard to this matter I agree with WILSON in
- asserting that, while with us, these birds do not feed on shell-fish. M.
- LESSON's words are as follows:--"Quoique le Bec-en-ciseaux semble defavorise par
- la forme de son bec, nous acquimes la preuve qu'il savait s'en servir avec
- avantage et avec la plus grande adresse. Les plages sabloneuses de Peuce sont
- en effect remplies de Mactres, coquilles bivalves, que la maree descendente
- laisse presque a sec dans des petites mares; le Bec-en-ciseaux tres au fait de
- cet phenomene, se place aupres de ces mollusques, attend que leur valves
- s'entrouvrent un peu, et profile aussitot de ce movement en enforcant la lame
- inferieure et tranchante de son bec entre les valves qui se reserrent.
- L'oiseaux enleve alors la coquille, la frappe sur la greve, coupe le ligament du
- mollusque, et peut ensuite avaler celui-ci sans obstacle. Plusieurs fois nous
- avons ete temoins de cet instinct tres perfectionne."
- While watching the movements of the Black Skimmer as it was searching for
- food, sometimes a full hour before it was dark, I have seen it pass its lower
- mandible at an angle of about 45 degrees into the water, whilst its moveable
- upper mandible was elevated a little above the surface. In this manner, with
- wings raised and extended, it ploughed as it were, the element in which its
- quarry lay to the extent of several yards at a time, rising and falling
- alternately, and that as frequently as it thought it necessary for securing its
- food when in sight of it; for I am certain that these birds never immerse their
- lower mandible until they have observed the object of their pursuit, for which
- reason their eyes are constantly directed downwards like those of Terns and
- Gannets. I have at times stood nearly an hour by the side of a small pond of
- salt water having a communication with the sea or a bay, while these birds would
- pass within a very few yards of me, then apparently quite regardless of my
- presence, and proceed fishing in the manner above described. Although silent at
- the commencement of their pursuit, they become noisy as the darkness draws on,
- and then give out their usual call notes, which resemble the syllables hurk,
- hurk, twice or thrice repeated at short intervals, as if to induce some of their
- companions to follow in their wake. I have seen a few of these birds glide in
- this manner in search of prey over a long salt-marsh bayou, or inlet, following
- the whole of its sinuosities, now and then lower themselves to the water, pass
- their bill along the surface, and on seizing a prawn or a small fish, instantly
- rise, munch and swallow it on wing. While at Galveston Island, and in the
- company of my generous friend EDWARD HARRIS and my son, I observed three Black
- Skimmers, which having noticed a Night Heron passing over them, at once rose in
- the air, gave chase to it, and continued their pursuit for several hundred
- yards, as if intent on overtaking it. Their cries during this chase differed
- from their usual notes, and resembled the barkings of a very small dog.
- The flight of the Black Skimmer is perhaps more elegant than that of any
- water bird with which I am acquainted. The great length of its narrow wings,
- its partially elongated forked tail, its thin body and extremely compressed
- bill, all appear contrived to assure it that buoyancy of motion which one cannot
- but admire when he sees it on wing. It is able to maintain itself against the
- heaviest gale; and I believe no instance has been recorded of any bird of this
- species having been forced inland by the most violent storm. But, to observe
- the aerial movements of the Skimmer to the best advantage, you must visit its
- haunts in the love season. Several males, excited by the ardour of their
- desires, are seen pursuing a yet unmated female. The coy one, shooting aslant
- to either side, dashes along with marvellous speed, flying hither and thither,
- upwards, downwards, in all directions. Her suitors strive to overtake her; they
- emit their love-cries with vehemence; you are gladdened by their softly and
- tenderly enunciated ha, ha, or the hack, hack, cae, cae, of the last in the
- chase. Like the female they all perform the most curious zigzags, as they
- follow in close pursuit, and as each beau at length passes her in succession, he
- extends his wings for an instant, and in a manner struts by her side. Sometimes
- a flock is seen to leave a sand-bar, and fly off in a direct course, each
- individual apparently intent on distancing his companions; and then their
- mingling cries of ha, ha, hack, hack, cae, cae, fill the air. I once saw one of
- these birds fly round a whole flock that had alighted, keeping at the height of
- about twenty yards, but now and then tumbling as if its wings had suddenly
- failed, and again almost upsetting, in the manner of the Tumbler Pigeon.
- On the 5th of May, 1837, I was much surprised to find a large flock of
- Skimmers alighted and apparently asleep, on a dry grassy part of the interior of
- Galveston Island in Texas, while I was watching some Marsh Hawks that were
- breeding in the neighbourhood. On returning to the shore, however, I found that
- the tide was much higher than usual, in consequence of a recent severe gale, and
- had covered all the sand banks on which I had at other times observed them
- resting by day.
- The instinct or sagacity which enables the Razor-bills, after being
- scattered in all directions in quest of food during a long night, often at great
- distances from each other, to congregate again towards morning, previously to
- their alighting on a spot to rest, has appeared to me truly wonderful; and I
- have been tempted to believe that the place of rendezvous had been agreed upon
- the evening before. They have a great enmity towards Crows and Turkey Buzzards
- when at their breeding ground, and on the first appearance of these marauders,
- some dozens of Skimmers at once give chase to them, rarely desisting until quite
- out of sight.
- Although parties of these birds remove from the south to betake themselves
- to the eastern shores, and breed there, they seldom arrive at Great Egg Harbour
- before the middle of May, or deposit their eggs until a month after, or about
- the period when, in the Floridas and on the coast of Georgia and South Carolina,
- the young are hatched. To these latter sections of the country we will return,
- reader, to observe their actions at this interesting period. I will present you
- with a statement by my friend the Rev. JOHN BACHMAN, which he has inserted in my
- journal. "These birds are very abundant, and breed in great numbers on the sea
- islands at Bull's Bay. Probably twenty thousand nests were seen at a time. The
- sailors collected an enormous number of their eggs. The birds screamed all the
- while, and whenever a Pelican or Turkey Buzzard passed near, they assailed it by
- hundreds, pouncing on the back of the latter, that came to rob them of their
- eggs, and pursued them fairly out of sight. They had laid on the dry sand, and
- the following morning we observed many fresh-laid eggs, when some had been
- removed the previous afternoon." Then, reader, judge of the deafening angry
- cries of such a multitude, and see them all over your head begging for mercy as
- it were, and earnestly urging you and your cruel sailors to retire and leave
- them in the peaceful charge of their young, or to settle on their lovely rounded
- eggs, should it rain or feel chilly.
- The Skimmer forms no other nest than a slight hollow in the sand. The
- eggs, I believe, are always three, and measure an inch and three quarters in
- length, an inch and three-eighths in breadth. As if to be assimilated to the
- colours of the birds themselves, they have a pure white ground, largely patched
- or blotched with black or very dark umber, with here and there a large spot of a
- light purplish tint. They are as good to eat as those of most Gulls, but
- inferior to the eggs of Plovers and other birds of that tribe. The young are
- clumsy, much of the same colour as the sand on which they lie, and are not able
- to fly until about six weeks, when you now perceive their resemblance to their
- parents. They are fed at first by the regurgitation of the finely macerated
- contents of the gullets of the old birds, and ultimately pick up the shrimps,
- prawns, small crabs, and fishes dropped before them. As soon as they are able
- to walk about, they cluster together in the manner of the young of the Common
- Gannet, and it is really marvellous how the parents can distinguish them
- individually on such occasions. This bird walks in the manner of the Terns,
- with short steps, and the tail slightly elevated. When gorged and fatigued,
- both old and young birds are wont to lie flat on the sand, and extend their
- bills before them; and when thus reposing in fancied security, may sometimes be
- slaughtered in great numbers by the single discharge of a gun. When shot at
- while on wing, and brought to the water, they merely float, and are easily
- secured. If the sportsman is desirous of obtaining more, he may easily do so,
- as others pass in full clamour close over the wounded bird.
-
-
- BLACK SKIMMER or SHEAR-WATER, Rhynchops nigra, Wils. Amer. Orn.,
- vol. vii. p. 85.
- RHINCOPS NIGRA, Bonap. Syn., p. 352.
- BLACK SKIMMER, Nutt. Man., vol. ii. p. 264.
- BLACK SKIMMER or RAZOR-BILLED SHEAR-WATER, Rhynchops nigra, Aud. Orn.
- Biog., vol. iv. p. 203.
-
-
- Male, 20, 48. Female, 16 3/4, 44 1/2.
- During winter, in vast multitudes on the coast of Florida. In summer
- dispersed in large flocks from Texas to New Jersey, breeding on sand beaches or
- islands. In the evenings and at night ascends streams sometimes to the distance
- of one hundred miles.
- Adult Male.
- Bill longer than the head, nearly straight, tetragonal at the base,
- suddenly extremely compressed, and continuing so to the end. Upper mandible
- much shorter than the lower, its dorsal outline very slightly convex, its ride
- sharp, the sides erect, more or less convex, the edges approximated so as to
- leave merely a very narrow groove between them; the tip a little rounded when
- viewed laterally. Nasal groove rather short, narrow near the margin; nostrils
- linear-oblong, sub-basal in the soft membrane. Lower mandible with the angle
- extremely short, the dorsal outline straight or slightly decurved, the sides
- erect, the edges united into a very thin blade which fits into the narrow groove
- of the upper mandible, the tip rounded or abrupt when viewed laterally.
- Head rather large, oblong, considerably elevated in front. Neck short and
- thick. Body short, ovate, and compact. Feet short, moderately stout; tibia
- bare below, with narrow transverse scutella before and behind; tarsus short,
- moderately compressed, anteriorly covered with broad scutella, reticulated on
- the sides and behind; toes very small; the first extremely short, and free; the
- inner much shorter than the outer, which is but slightly exceeded by the middle
- toe; the webs very deeply concave at the margin, especially the inner. Claws
- long, compressed, tapering, slightly arched, rather obtuse, the inner edge of
- the middle toe dilated and extremely thin. Plumage moderately full, soft, and
- blended; the feathers oblong and rounded. Wings extremely elongated, and very
- narrow; the primary quills excessively long; the first longest, the rest rapidly
- graduated; the secondaries short, broad, incurved, obliquely pointed, some of
- the inner more elongated. Tail rather short, deeply forked, of twelve feathers,
- disposed in two inclined planes.
- Bill of a rich carmine, inclining to vermilion for about half its length,
- the rest black. Iris hazel. Feet of the same colour as the base of the bill,
- claws black. The upper parts are deep brownish-black; the secondary quills, and
- four or five of the primaries, tipped with white; the latter on their inner web
- chiefly. Tail-feathers black, broadly margined on both sides with white, the
- outer more extensively; the middle tail-coverts black, the lateral black on the
- inner and white on the outer web. A broad band of white over the forehead,
- extending to the fore part of the eye; cheeks and throat of the same colour; the
- rest of the neck and lower parts in spring and summer of a delicate
- cream-colour; axillary feathers, lower wing-coverts, and a large portion of the
- secondary quills, white; the coverts along the edge of the wing black.
- Length from point of upper mandible to end of tail 20 inches, to end of
- wings 24 1/2, to end of claws 17; to carpal joint 8 1/4; extent of wings 48;
- upper mandible 3 1/8; its edge 3 7/8; from base to point of lower mandible
- 4 1/2; depth of bill at the base 1; wing from flexure 15 3/4; tail to the fork
- 3 1/2; to end of longest feather 5 1/4; tarsus 1 1/4; hind toe and claw 4/12;
- middle toe 10/12, its claw 4/12. Weight 13 oz.
- The Female, which is smaller, is similar to the male, but with the
- tail-feathers white excepting a longitudinal band including the shaft.
- Length to end of tail 16 3/4, to end of wings 20 1/4, to end of claws
- 16 1/4, to carpus 8; extent of wings 44 1/2. Weight 10 oz.
- After the first autumnal moult there is on the hind part of the neck a
- broad band of white, mottled with greyish-black; the lower parts pure white, the
- upper of a duller black; the bill and feet less richly coloured.
- Length to end of tail, 16 3/4 inches, to end of wings 20, to end of claws
- 14 1/2, to carpus 6 3/8; extent of wings 42.
- In some individuals at this period the mandibles are of equal length.
- The palate is flat, with two longitudinal series of papillae directed
- backwards. The upper mandible is extremely contracted, having internally only a
- very narrow groove, into which is received the single thin edge of the lower
- mandible. The posterior aperture of the nares is 1 3/12 inches long, with a
- transverse line of papillae at the middle on each side, and another behind. The
- tongue is sagittiform, 6 1/2 twelfths long, with two conical papillae at the
- base, soft, fleshy, flat above, horny beneath. Aperture of the glottis 4 1/2
- twelfths long, with numerous small papillae behind. Lobes of the liver equal,
- 1 1/2 inches long. The heart of moderate size, 1 1/12 long, 10 twelfths broad.
- The oesophagus, of which only the lower portion, [a], is seen in the
- figure, is 8 inches long, gradually contracts from a diameter of 1 inch to 4
- twelfths, then enlarges until opposite the liver, where its greatest diameter is
- 1 4/12. Its external transverse fibres are very distinct, as are the internal
- longitudinal. The proventriculus, [b], is 9 twelfths long, its glandules
- extremely small and numerous, roundish, scarcely a quarter of a twelfth in
- length. The stomach, [c d e], is rather small, oblong, 1 inch 4 twelfths
- long, 11 twelfths broad, muscular, with the lateral muscles moderate. The
- cuticular lining of the stomach is disposed in nine broad longitudinal rugae of
- a light red colour, as in the smaller Gulls and Terns. Its lateral muscles are
- about 4 twelfths thick, the tendons, [e], 6 twelfths in diameter. The intestine
- is 2 feet 4 inches long, its average diameter 2 1/2 twelfths. The rectum is 2
- inches long. One of the coeca is 4, the other 3 twelfths, their diameter 1 1/4
- twelfths.
- In another individual, the intestine is 22 1/4 inches long; the coeca 5
- twelfths long, 1 twelfth in diameter; the rectum 1 3/4 inches long; the cloaca 9
- twelfths in diameter.
- The trachea is 5 3/4 inches long, round, but not ossified, its diameter at
- the top 5 twelfths, contracting gradually to 2 1/2 twelfths. The lateral or
- contractor muscles are small; the sterno-tracheal slender; there is a pair of
- inferior laryngeals, going to the last ring of the trachea. The number of rings
- is 90, and a large inferior ring. The bronchi are of moderate length, but
- wider, their diameter being 3 1/2 twelfths at the upper part; the number of
- their half-rings about 18.
- The digestive organs of this bird are precisely similar to those of the
- Terns and smaller Gulls, to which it is also allied by many of its habits.
-