Audubon's Birds/BIRDSVER1_3.BIN/dp/0071/00712.txt

Text File | 1992-08-27 | 22KB | 323 lines

$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 gl