Family XLI. PELECANINAE. PELECANS. GENUS V. SULA, Briss. Gannet. |
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Family |
THE BOOBY GANNET. [Brown Booby.] |
Genus | SULA FUSCA, Linn. [Sula leucogaster.] |
As the Marion was nearing the curious islets of the Tortugas, one of the
birds that more particularly attracted my notice was of this species. The
nearer we approached the land, the more numerous did they become, and I felt
delighted with the hope that ere many days should elapse, I should have an
opportunity of studying their habits. As night drew her sombre curtain over the
face of nature, some of these birds alighted on the top-yard of our bark, and I
observed ever afterwards that they manifested a propensity to roost at as great
a height as possible above the surrounding objects, making choice of the tops of
bushes, or even upright poles, and disputing with each other the privilege. The
first that was shot at, was approached with considerable difficulty: it had
alighted on the prong of a tree which had floated and been fastened to the
bottom of a rocky shallow at some distance from shore; the water was about four
feet deep and quite rough; sharks we well knew were abundant around us; but the
desire to procure the bird was too strong to be overcome by such obstacles. In
an instant, the pilot and myself were over the sides of the boat, and onward we
proceeded with our guns cocked and ready. The yawl was well manned, and its
crew awaiting the result. After we had struggled through the turbulent waters
about a hundred yards, my companion raised his gun and fired; but away flew the
bird with a broken leg, and we saw no more of it that day. Next day, however,
at the same hour, the Booby was seen perched on the same prong, where, after
resting about three hours, it made off to the open sea, doubtless in search of
food.
About eight miles to the north-east of the Tortugas lighthouse, lies a
small sand-bar a few acres in extent, called Booby Island, on account of the
number of birds of this species that resort to it during the breeding-season,
and to it we accordingly went. We found it not more than a few feet above the
surface of the water, but covered with Boobies, which lay basking in the
sunshine, and pluming themselves. Our attempt to land on the island before the
birds should fly off, proved futile, for before we were within fifty yards of
it, they had all betaken themselves to flight, and were dispersing in various
directions. We landed, however, distributed ourselves in different parts, and
sent the boat to some distance, the pilot assuring us that the birds would
return. And so it happened. As they approached, we laid ourselves as flat as
possible in the sand, and although none of them alighted, we attained our
object, for in a couple of hours we procured thirty individuals of both sexes
and of different ages, finding little difficulty in bringing them down as they
flew over us at a moderate height. The wounded birds that fell on the ground
made immediately for the water, moving with more ease than I had expected from
the accounts usually given of the awkward motions of these birds on the land.
Those which reached the water swam off with great buoyancy, and with such
rapidity, that it took much rowing to secure some of them, while most of those
that fell directly into the sea with only a wing broken, escaped. The island
was covered with their dung, the odour of which extended to a considerable
distance leeward. In the evening of the same day we landed on another island,
named after the Noddy, and thickly covered with bushes and low trees, to which
thousands of that species of Tern resort for the purpose of breeding. There
also we found a great number of Boobies. They were perched on the top branches
of the trees, on which they had nests, and here again we obtained as many as we
desired. They flew close over our heads, eyeing us with dismay but in silence;
indeed, not one of these birds ever emitted a cry, except at the moment when
they rose from their perches or from the sand. Their note is harsh and
guttural, somewhat like that of a strangled pig, and resembling the syllables
hork, hork.
The nest of the Booby is placed on the top of a bush at a height of from
four to ten feet. It is large and flat, formed of a few dry sticks, covered and
matted with sea-weeds in great quantity. I have no doubt that they return to
the same nest many years in succession, and repair it as occasion requires. In
all the nests which I examined, only one egg was found, and as most of the birds
were sitting, and some of the eggs had the chick nearly ready for exclusion, it
is probable that these birds raise only a single young one, like the Common
Gannet or Solan Goose. The egg is of a dull white colour, without spots, and
about the size of that of a common hen, but more elongated, being 2 3/8 inches
in length, with a diameter of 1 3/4. In some nests they were covered with filth
from the parent bird, in the manner of the Florida Cormorant. The young, which
had an uncouth appearance, were covered with down; the bill and feet of a deep
livid blue or indigo colour. On being touched, they emitted no cry, but turned
away their heads at every trial. A great quantity of fish lay beneath the trees
in a state of putrefaction, proving how abundantly the young birds were supplied
by their parents. Indeed, while we were on Noddy Island, there was a constant
succession of birds coming in from the sea with food for their young, consisting
chiefly of flying-fish and small mullets, which they disgorged in a half
macerated state into the open throats of their offspring. Unfortunately the
time afforded me on that coast was not sufficient to enable me to trace the
progress of their growth. I observed, however, that none of the birds which
were still brown had nests, and that they roosted apart, particularly on Booby
Island, where also many barren ones usually resorted, to lie on the sand and
bask in the sun.
The flight of the Booby is graceful and extremely protracted. They pass
swiftly at a height of from twenty yards to a foot or two from the surface,
often following the troughs of the waves to a considerable distance, their wings
extended at right angles to the body; then, without any apparent effort, raising
themselves and allowing the rolling waters to break beneath them, when they tack
about, and sweep along in a contrary direction in search of food, much in the
manner of the true Petrels. Now, if you follow an individual, you see that it
suddenly stops short, plunges headlong into the water, pierces with its powerful
beak and secures a fish, emerges again with inconceivable ease, after a short
interval rises on wing, performs a few wide circlings, and makes off toward some
shore. At this time its flight is different, being performed by flappings for
twenty or thirty paces, with alternate sailings of more than double that space.
When overloaded with food, they alight on the water, where, if undisturbed, they
appear to remain for hours at a time, probably until digestion has afforded them
relief.
The range to which this species confines itself along our coast, seldom
extends beyond Cape Hatteras to the eastward, but they become more and more
numerous the farther south we proceed. They breed abundantly on all such
islands or keys as are adapted for the purpose, on the southern and western
coasts of the Floridas and in the Gulf of Mexico, where I was told they breed on
the sand-bars. Their power of wing seems sufficient to enable them to brave the
tempest, while during a continuance of fair weather they venture to a great
distance seaward, and I have seen them fully 200 miles from land.
The expansibility of the gullet of this species enables it to swallow
fishes of considerable size, and on such occasions their mouth seems to spread
to an unusual width. In the throats of several individuals that were shot as
they were returning to their nests, I found mullets measuring seven or eight
inches, that must have weighed fully half a pound. Their body, beneath the
skin, is covered with numerous air-cells, which probably assist them in raising
or lowering themselves while on wing, and perhaps still more so when on the
point of performing the rapid plunge by which they secure their prey.
Their principal enemies during the breeding-season are the American Crow
and the Fish Crow, both of which destroy their eggs, and the Turkey Buzzard,
which devours their young while yet unfledged. They breed during the month of
May, but I have not been able to ascertain if they raise more than one brood in
the season. The adult birds chase away those which are yet immature during the
period of incubation. It would seem that they take several years in attaining
their perfect state.
When procured alive, they feed freely, and may be kept any length of time,
provided they are supplied with fish. No other food, however, could I tempt
them to swallow, excepting slices of turtle, which after all they did not seem
to relish. In no instance did I observe one drinking. Some authors have stated
that the Frigate Pelican and the Lestris force the Booby to disgorge its food
that they may obtain it; but this I have never witnessed. Like the Common
Gannet, they may be secured by fastening a fish to a soft plank, and sinking it
a few feet beneath the surface of the water, for if they perceive the bait,
which they are likely to do if they pass over it, they plunge headlong upon it,
and drive their bill into the wood.
When a Booby has alighted on the spar of a vessel, it is no easy matter to
catch it, unless it is much fatigued; but if exhausted and asleep, an expert
seaman may occasionally secure one. I was informed that after the
breeding-season, these birds roost on trees in company with the Brown Pelican
and a species of Tern, Sterna stolida, and spend their hours of daily rest on
the sand-banks. Our pilot, who was a man of great observation, assured me that
while at Vera Cruz, he saw the fishermen there go to sea, and return from
considerable distances, simply by following the course of the Boobies.
The bills and legs of those which I procured in the brown plumage, and
which were from one to two years of age, were dusky-blue. These were undergoing
moult on the 14th of May. At a more advanced age, the parts mentioned become
paler, and when the bird has arrived at maturity, are as represented in my
plate. I observed no external difference between the sexes in the adult birds.
The stomach is a long dilatable pouch, thin, and of a yellow colour. The body
is muscular, and the flesh, which is of a dark colour, tough, and having a
disagreeable smell, is scarcely fit for food.
I am unable to find a good reason for those who have chosen to call these
birds boobies. Authors, it is true, generally represent them as extremely
stupid; but to me the word is utterly inapplicable to any bird with which I am
acquainted. The Woodcock, too, is said to be stupid, as are many other birds;
but my opinion, founded on pretty extensive observation, is, that it is only
when birds of any species are unacquainted with man, that they manifest that
kind of ignorance or innocence which he calls stupidity, and by which they
suffer themselves to be imposed upon. A little acquaintance with him soon
enables them to perceive enough of his character to induce them to keep aloof.
This I observed in the Booby Gannet, as well as in the Noddy Tern, and in
certain species of land birds of which I have already spoken. After my first
visit to Booby Island in the Tortugas, the Gannets had already become very shy
and wary, and before the Marion sailed away from those peaceful retreats of the
wandering sea-birds, the Boobies had become so knowing, that the most expert of
our party could not get within shot of them.
SULA FUSCA, Bonap. Syn., p. 408.
BOOBY, Sula fusca, Nutt. Man., vol. ii. p. 500.
BOOBY GANNET, Sula fusca, Aud. Orn. Biog., vol. iii. p. 63.
Male, 31, 49 1/4.
Gulf of Mexico, and as far east as the coast of Georgia. Breeds on the
Tortugas Keys, south of Florida. Abundant. Migratory.
Adult Male.
Bill longer than the head, opening beyond the eyes, straight,
elongated-conical, broader above than beneath at the base, compressed. Upper
mandible with the dorsal line convex at the base, then a little concave, and
towards the tip slightly arched, ridge very broad, convex, separated by a seam
on each side from the sides, which are nearly perpendicular, edges sharp,
inflected, serrated, tip acute. No external nostrils. Lower mandible prolonged
at the base behind the upper, its angle very long, wide at the base, with a bare
membrane, very narrow towards the end, dorsal line straight, ascending, sides
convex, tip very acute, edges serrated towards the end.
Head rather large; neck rather long and thick; body of moderate bulk,
rather elongated; wings long. Feet short, strong, placed rather far behind;
tibiae concealed; tarsus very short, rounded before, sharp behind, covered all
round with reticular scales; toes all united by membranes; first very short,
being about half the length of the second, third and fourth longest and nearly
equal, but the claw of the third is much longer than that of the fourth; claws
small, compressed, acute, curved, that of the third toe largest, depressed,
curved outwards, with a thin pectinated inner edge.
Plumage generally short, close, rather compact, the feathers small and
rounded; those on the head very small; loral and orbital spaces bare, as is that
in the angle of the lower mandible, and a short space above the tibio-tarsal
joint; wings long, acute, narrow; primaries strong, narrow, tapering rapidly to
a rounded point, first and second longest and about equal, the rest rapidly
graduated; secondaries short, rather broad, narrowed towards the rounded point.
Tail rather long, cuneate, of twelve narrow, tapering feathers.
Bill and naked parts at its base bright yellow, pale flesh-coloured towards
the end; a dusky spot before the eye. Iris white. Tarsi, toes, and their
connecting webs, pale yellow, claws white. Head, neck all round, upper parts in
general, and lower surface of wings, dusky-brown, tinged with grey; the breast,
abdomen, and lower tail-coverts, pure white.
Length 31 inches, to end of claws 27, extent of wings 29 1/4; bill along
the back 3 11/12, along the edge 5; tarsus 1 8/12, middle toe and claw 3 1/2.
Wing from flexure 16 1/2, tail 8 1/2. Weight 3 lbs. 4 1/2 oz.
The Female resembles the male, but is smaller.
The Young, when fledged, are of a greyish-brown colour all over, the breast
and abdomen being merely a little lighter than the rest. The bill and claws are
dusky, the tarsi and toes with their membranes dull yellow.
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