McCORMICK'S SKUA GULL
A book which treats of Adelie penguins scarcely can be complete without
reference to the beautiful McCormick's skua gull (_Megalestris
maccormicki_), as probably no Adelie rookery exists without its
attendant band of skuas, who build their own nests very close to and
occasionally among those of the penguins on whom they prey, almost
entirely supporting themselves and their young upon the eggs and young
offspring of their hosts.
Mention has been made of these birds from time to time through the
previous pages, and some idea of their habits already will have been
formed. In point of fearlessness they fall somewhat short of the Adelie,
but exhibit, perhaps, rather more caution in their dealings with man
than the gulls who visit St. James's Park in London and are fed by the
children there, frequently from the hand, though probably in a very few
days they might become extremely tame were their short experience of
mankind made less bitter. The majority of explorers, like most men,
though kindly by nature, are entirely thoughtless in their dealings with
wild animals, and the skuas approach them only to be killed or severely
injured by the ice-axes or rocks that are thrown at them in wanton sport
as they light on the ground or hover near the visitors, whom they
quickly discover to be their bitter and relentless foes.
Arriving at the rookeries somewhat later than the Adelies, they do not
lay their eggs until the beginning of December. Practically no nest is
made, a mere hollow being worked in the ground, in which the bird sits.
Frequently several hollows are made before the hen finally settles where
she will lay. The two eggs, which are brownish olive thickly and darkly
mottled with brown, are incubated for four weeks, after which the chicks
are hatched.
From the moment of their first appearance from the egg these chicks
exhibit the most extraordinary precocity. Covered with pale slaty-grey
down, they look anything but the pugnacious little animals they turn out
to be. Their one idea, besides feeding, seems to be to fight one
another, and they may be seen to roll about the nest, locked together,
fighting with beak and claw. They are fed from the ground, and may be
seen picking about among the stones like the little domestic chickens,
which they very much resemble. After a time invariably one of the chicks
disappears, and as dead youngsters are not to be found, they are
probably eaten by neighbours who have caught them wandering; in fact,
Mr. Ferrar, of Captain Scott's first expedition, actually saw a Skua
pick up a wandering chick of its own species and fly off with it,
followed by a screaming flock of its neighbours, who sought to rob it of
its prey.
In order to find out how many eggs a Skua would lay, I marked some
nests, and took the eggs as they were laid. In each case a second egg
was laid, but when this was taken no more appeared. In two nests I
removed the first egg as soon as it was laid, but left the second, which
was then sat upon by the parent, who was content with it, or unable to
lay a third.
When any of us approached their nests the old birds would fly round in
wide circles, making wild "stoops" at our heads each time they passed
over us, in the evident attempt to frighten us away. Occasionally they
would actually knock our heads with a wing, and nothing seeming to scare
them off, they would swoop past us time after time in a most
disconcerting manner. In order to keep them at a distance without having
to keep a constant look-out, when I was in the neighbourhood of their
nest, I used to walk about holding a ski-stick or the handle of my
ice-axe straight above me, and they would swoop at the top of this
instead of my head, which was infinitely preferable. One day when a high
wind was blowing on top of Cape Adare, I had my ice-axe knocked clean
out of my hand by one of the Skuas flying straight into the handle, the
heavy blow seeming to affect the bird but slightly.
There was a "skuary" on the screes, close to a thickly populated part of
the rookery, but the majority of these birds made their nests right at
the top of Cape Adare, from which point of vantage they surveyed the
entire rookery, and a very sharp look-out they kept too, for no sooner
did we start to flense a seal than a flock of them descended to gobble
at the lumps of blubber as we threw them on the ground. In this
occupation they exhibited the greatest jealousy, and when there was a
hundred times as much blubber on the ground as all the skuas possibly
could have eaten, they continually tried to drive each other away. When
fighting they rarely stayed on the ground, but leapt at one another into
the air, and one of the illustrations shows two Skuas in the act of
doing this. Their great spread of wing is well shown in this photograph.
(Fig. 71.)
When penguins' eggs were plentiful in the rookery the Skuas flew very
low over the ground, and as they passed over each colony of nests the
sitting birds would crouch low upon them, a very necessary precaution,
as I have described already in these pages the unerring way in which the
Skuas picked up the penguins' eggs when they were left uncovered. Broken
and empty shells strewed the ground in the vicinity of the Skuas' nests,
and it is probable that in a large rookery, such as that at Cape Adare,
thousands of eggs are destroyed by them annually.
The instinct of the thief is most strongly marked in the Skua tribe, and
I am afraid that the mere love of thieving alone actuates them on many
occasions. For instance, when I was skinning a seal one day near Cape
Evans I left a pair of field-glasses lying on a coat close by, and on
looking round saw a Skua in the act of making off with them, holding
them by the strap in his beak. A sudden yell caused the offender to drop
the glasses, fortunately when they were but a yard from the ground.
Again, when the crew of an Antarctic ship were engaged in blasting the
sea-ice which imprisoned it, a Skua flew off with one of the detonators
which had been left on the ice. I think the detonator contained
dynamite, but at any rate I am told that there was a stampede on the
part of the men to get away from under the bird as it flew overhead!
When, with two companions, I visited a skuary at the back of the penguin
rookery at Cape Royds, the Skuas circled over us in a way I have
described above, but instead of swooping at our heads, some of them
repeatedly dropped their guano on to us as they passed over, timing the
process with such surprising accuracy that I was hit once, and Commander
Campbell no less than three times. The following year when at Cape
Adare, I expected the same treatment from the Skuas there, but curiously
enough, these never did it. That one skuary should have adopted such
tactics and another not, is a very curious thing, but it may possibly be
that the Cape Royds Skuas discovered the trick during the stay of Sir
Ernest Shackleton's expedition, who had spent a year there quite
recently, and of the _Discovery_ expedition which spent two years at Hut
Point, but a few miles distant, whereas the only men who ever inhabited
Cape Adare wintered there some fifteen years before. But this is mere
speculation.
[Illustration: Fig. 71. "Leapt at one another into the Air" (Page 129)]
[Illustration: Fig. 72. A Skua by its Chick (Page 131)]
When one of the parent Skuas is on the ground near its nest, on the
approach of anyone it throws its head back, opens its wings, and loudly
proclaims its whereabouts with its raucous cawing notes. When hovering
over food, and at other times when not alarmed or angry, the sounds made
by a Skua are very like those of the common Herring Gull, and not
altogether unmusical at times, especially when making the little shrill
piping note, by which I have often thought that gulls so nearly imitate
the squeaking of a block in its sheaf.
When the penguin chicks are hatched, the Skuas prey upon these in a most
cruel manner, and should a chick wander away from the protecting old
birds, a Skua is almost certain to pounce upon and kill it. This it does
by pecking its eyes out, after which, with powerful strokes of its beak,
it gets to work on its back and quickly devours the kidneys.
The dead bodies of hundreds of chicks are seen strewn about the rookery,
and especially in the neighbourhood of the Skuas' nests, as very often
they carry them there. All these dead chicks are seen to have two holes
picked through their backs, one on each side, corresponding to the
position of each kidney.
Besides the penguins' eggs and young, there is another fruitful source
of food for the Skuas to be found along the Antarctic coasts at the
early part of the year, and that is during the time when the seals are
bringing forth their young upon the sea-ice. The Skuas attend upon them
then, and devour the after-births. In the second volume of the
_Discovery_ reports Dr. Wilson mentions that large numbers of Skuas were
noticed at Granite Harbour, and I have no doubt that they had
congregated there for this purpose, as when passing the spot on a spring
journey along the sea-ice in 1912, we saw many hundreds of Weddell seals
with their young. So many were there, that as we lay in our
sleeping-bags during the night, the bleating of the little calves near
our tents conveyed to our half-awakened senses the impression that we
were in the midst of lambing fields at home!
* * * * *
The soft parts are coloured as follows:
_Bill_, black.
_Iris_, dark brown.
_Legs_, _toes_, and _webbs_, black, excepting a patch of bright blue
just above the tibio-metatarsal joint, in young fledglings. Wholly black
afterwards. (They have a very fine spread of webb.)
_Claws_, black.
The feathers of the head, neck, and breast vary from very light buff, or
almost white, to rich dark brown.
Skuas' Time Table
+--------------------+-------------------+------------+
| | McMurdo Sound | Cape Adare |
+--------------------+-------------------+------------+
| | 1902 1903 | 1911 |
| 1st bird arrived | Nov. 3 Oct. 25 | Oct. 26 |
| 1st egg seen | Dec. 9 Dec. 2 | Nov. 29 |
| 1st chick hatched | Jan. 1 | |
| Last bird left | Mar. 30 Apr. 7 | |
+--------------------+-------------------+------------+
A SHORT NOTE ON EMPEROR PENGUINS(9)
(9) _Aptenodytes forsteri._
The Emperor is by far the largest of all penguins, weighing between 80
and 90 lbs. It is also a particularly handsome and graceful bird. By
nature it seems much like the Adelie, except that its general demeanour
is extremely dignified, and its gait, as it approaches you over the
snow, slow and deliberate.
The most marked difference in the habits of the Adelie and the Emperor
lies in the respective seasons at which each lays and incubates its
eggs. Unlike the Adelie, which, as we have seen, chooses the warmest and
lightest months of the year for the rearing of its young, the Emperor
performs this duty in the darkest, coldest, and most tempestuous time.
The only reason that has been suggested for this custom is that many
months must pass before the chicks are fully fledged. Were they hatched
in December (midsummer) as are Adelies, autumn would find them still
unfledged, and probably they would perish in consequence, whereas, being
hatched in the early spring, they are fostered by their parents until
the warmer weather begins, and then have the entire summer in which to
accomplish their change of plumage.
[Illustration: Fig. 73. AN EMPEROR PENGUIN (Page 134)]
The only Emperor rookery known to man at the present day was discovered
by Lieuts. Royds and Skelton, of Captain Scott's first Antarctic
expedition, on the sea-ice beneath Cape Crozier. Here in the dark days
of July this extraordinary bird lays its one egg upon the ice.
In the winter of 1911 a very brave journey was made to this spot by a
party of Captain Scott's officers, consisting of Dr. Wilson, Lieut.
Bowers and Mr. Cherry-Garrard. The experiences of this little band were
so terrible that it is remarkable they ever returned to tell of them.
Temperatures of -78 deg. F. were encountered, and the most severe blizzards
at lower temperatures than any sledging-party had yet endured. Under
these truly terrible conditions the Emperors lay their eggs and hatch
their young.
The mortality under such circumstances is very high, as one would
expect. Avalanches of ice fall from the cliffs above, crushing many of
the parent birds, and causing hundreds of eggs to be deserted. As Dr.
Wilson stated, the ice cliffs beneath which these remarkable animals sat
were so unstable that no man in his senses would camp for a single night
beneath them. In spite of this, evidence showed that after an avalanche
of ice blocks from above, which had caused some of the Emperors to leave
their eggs on the ice and bolt in terror, many of them had returned and
continued to sit on the eggs which had been frozen and killed by the
frost in their absence, continuing to do so long after they were
completely rotten. Indeed, in their desire for something to hatch, some
who had been deprived of their eggs, were seen to be attempting to
incubate pieces of ice in their place, and, unlike Adelies, they seem
ever ready to snatch and foster the young of their neighbours.
The first time the rookery at Cape Crozier was visited, not above one
thousand birds occupied it. On the second occasion their numbers were
far short of this. By the springtime only one out of ten or twelve birds
are seen to be rearing young, so it is obvious other rookeries await
discovery in other parts, as there are a large number of Emperors to be
seen along the Antarctic coasts.
[Illustration: Fig. 74. PROFILE OF AN EMPEROR (Page 134)]
When in the _Terra Nova_ we made our way along the face of the great
Barrier to the eastward, we saw large numbers of Emperors, especially to
the extreme eastward where a heavy hang of pack-ice blocked our further
passage, and I have little doubt that future exploration will disclose a
rookery or rookeries in this direction.
Again, in the spring of 1912, when nearing the end of a sledge journey
from the northward to Cape Evans we passed large gatherings of Emperor
penguins on some very old sea-ice under the Barrier's edge, along the
southern end of McMurdo Sound, and it seems not at all unlikely that
they may breed here too. Unfortunately we were unable at that time to
make detours, so had to leave the question unsettled, but if they do
breed here, they must have far to go to get food during those winters
when the sea-ice does not break out of the Sound.
The growth of the Emperor chick is slow, when compared with the
mushroom-like rate at which the Adelie youngster increases its
substance.
Approximately the egg is laid at the beginning of July and hatched out
some seven or eight weeks later. During the period of incubation, which
duty is shared by all, male and female alike, the egg is held in a loose
fold of skin at the lower part of the abdomen, the skin of the adults
being worn bare of feathers in this region.
When hatched out, the chick is coveted by every unoccupied adult, and so
desperate at times are the struggles for its possession that very
frequently it gets injured or killed by its would-be foster parents. Dr.
Wilson has estimated the mortality among the chicks before they shed
their down at 77 per cent. and thinks that half this number are killed
by kindness. Very often, in fact, they will crawl under projecting
ledges of ice, or anywhere to escape the attentions of half a dozen or
so of adults, all bearing down upon them together, only to meet and
struggle for their possession, during which process the innocent cause
may get trampled and clawed to death. So strong is the maternal instinct
of the Emperor, that frozen and lifeless chicks are carried about and
nursed until their down is worn away. In fact, the scientists who
visited the rookery were unable to get good specimens of dead chicks, as
all of these had been treated in this way.
Fortunately the Emperor chick escapes the depredation of the Skua gull,
which plays such havoc in the Adelie rookeries, because the Skua does
not come south until the summer, by which time the Emperor chicks are
well grown. As in the case of the Adelies, the black throat is not
acquired until the second moult. When this has taken place, the bird
looks remarkably handsome. The bill, which is curved and tapering, is
bluish black, but the posterior half of the mandible is coloured a
beautiful lilac. The head and throat are black, whilst on each side of
the neck is a patch of vivid orange feathers. The rest of the body is
marked in the same way as the Adelie.
The mortality among the chicks being so very high, the probability is
that the life of the adult is long, as otherwise the species could
hardly survive. Dr. Herbert Klugh has calculated that the Emperor
penguin lives for thirty-five years.
Evidence goes to show that the young birds spend their immaturity on the
pack-ice, as all those sighted and collected on the pack at any distance
to the northward have been immature, and no immature birds have been
seen along the coasts at any time during the summer.
The food of the Emperor mainly consists of fish and crustaceans. There
are invariably many small pebbles in the stomach. Like Adelies they must
of course have open water within reach in order to get food, and in the
neighbourhood of Cape Crozier this is always to be found, as the rapid
tide there keeps the sea from freezing in over a considerable area, so
that probably they never have to walk more than a mile or two to get
food.
The cry of the Emperor is very loud and travels far across the ice. When
sledging over the sea-ice in the spring, in the neighbourhood of Cape
Adare, a curious sound was heard at times, reminding one strongly of the
"overtone" notes of a ship's steam horn. The sounds puzzled us at the
time, but I think now that most probably they were made by Emperor
penguins.
The egg of the Emperor is white, pyriform in shape, and weighs just
under 1 lb.
My own experience of these birds being limited I do not intend to enter
deeply into the subject. The only surviving member of the band who
visited Cape Crozier during the winter is Mr. Cherry-Garrard, and it is
much to be hoped that some day he will write us an account of what he
saw there. In the meantime for further details of the habits and
morphology of the species, the reader is referred to Dr. Wilson's work,
published in the second volume of the British Museum Reports, on the
National Antarctic Expedition 1901-1904.
PRINTED AT
THE BALLANTYNE PRESS
LONDON
[ Transcriber's Note:
The following is a list of corrections made to the original.
The first line is the original line, the second the corrected one.
SOME ARE WALKING AND SOME "TOBOGANNING" (Page 28)]
SOME ARE WALKING AND SOME "TOBOGGANING" (Page 28)]
[Illustration: Fig. 51. SEA LEOPARDS "LURK BENEATH THE OVERHANGING
[Illustration: Fig. 51. SEA-LEOPARDS "LURK BENEATH THE OVERHANGING
confusion, causing them to 'porpoise" madly away for a few hundred
confusion, causing them to "porpoise" madly away for a few hundred
blackish on dorsum; maxilla blackish on cutting edges. _Feet_, white on
blackish on dorsum; maxilla, blackish on cutting edges. _Feet_, white on
eggs. Unlike the Adelie, which, as we have seen, choses the warmest and
eggs. Unlike the Adelie, which, as we have seen, chooses the warmest and
]
End of Project Gutenberg's Antarctic Penguins, by George Murray Levick