WHAT HAS BECOME OF THE WHALE’S LEGS
If a whale is struck near the tail by the harpoon it is almost powerless
to pull because the strain on the rope straightens out its body and the
animal can swim only with difficulty. Practically all of the forward
motion is developed by means of the flukes and the side fins are only
used as balancing organs and in turning and rising to the surface. The
flukes are not twisted in a rotary movement like the propeller of a
ship, as is commonly believed, but wave straight up and down.
While hunting in Alaska I had an excellent opportunity to see the manner
in which a whale swims. I had climbed to the barrel at the masthead
while we were following an enormous humpback and as the water was like
glass save for the long swell, I could see 15 or 20 feet beneath the
surface.
Suddenly the dim outlines of the whale took shape in the green depths
far below me but when near the surface the animal checked its upward
rush, turned downward, and dove directly under the ship, rising a
hundred fathoms away on the port beam. I could see every movement of the
great body as clearly as though the whale had been suspended in mid-air.
When the animal turned, the side fins were thrown outward but were
pressed close to the body as it swam under the ship.
[Illustration:
Posterior view of a blue whale on the slip at Aikawa, Japan. The
flukes have been cut off and the wide thin caudal portion of the
body is well shown.
]
A whale’s flippers must not be compared with the fins of a fish, for in
structure the two are quite unlike. The flippers of all cetaceans are
merely the fore-limbs of ordinary land mammals, which have become
overlaid with blubber to form a paddle in adaptation to an aquatic life
and have the bones, blood vessels, and nerves of the human arm. The
flipper of the humpback whale has four greatly elongated fingers but in
some other species there are five fingers as in the human hand.
Cetaceans also have rudiments of the hind-limbs. These consist of the
pelvis, which is fairly well developed, and small nodules of bone
representing the femur and sometimes the tibia; the latter is
cartilaginous except in rare cases. These rudiments are, of course,
entirely concealed within the body and can only be found by carefully
cutting away the flesh surrounding the sexual organs.
[Illustration:
The flipper of a humpback whale. “The flippers of all cetaceans are
merely the fore-limbs of ordinary land mammals, which have become
overlaid with blubber to form a paddle.”
]
One of the most striking things about the blue whale, and indeed all its
relatives, are the folds which extend longitudinally from the lower jaw
backward over the throat, breast, and abdomen. In different species of
whales the folds vary in number and width, the furrows between them
being about an inch in depth and the skin capable of great extension.
The use of the folds has been a subject of disagreement among
naturalists, but my own belief is that they are an adaptation to
increase the mouth capacity and to give greater power of expansion to
the lungs.
[Illustration:
After the humpback’s flipper has been stripped of blubber. The
forearm, wrist and fingers are shown. In this species the digits
have been reduced to four and are greatly elongated.
]
The folds are not composed of flesh but entirely of blubber, the layer
of fibrous fat which covers the bodies of all whales, porpoises, and
dolphins and lies between the skin and the flesh. Since cetaceans are
warm-blooded animals (fish and reptiles are cold-blooded) it is
necessary for them to have some protection from the cold. Hair is not
sufficient for this purpose as in land mammals; consequently the layer
of blubber, which acts as a non-conductor and prevents the heat of the
animal’s body from being absorbed by the water, has been developed. It
is from this that the whale oil of commerce is boiled or tried out. The
blubber may be easily peeled off the body in strips called “blanket
pieces,” which are cut into blocks and after being sliced are put into
the trying out kettles.
[Illustration:
The folds on the throat of a finback whale. Probably the folds are an
adaptation to increase the mouth capacity and to give greater power
of expansion to the lungs.
]
When one of these great pieces of blubber is being torn off a whale’s
body it sometimes gives way and springs back with tremendous force. At
the Oshima station in Japan, my cook who had one day been pressed into
service when several whales were waiting to be cut in was struck fairly
upon the head by a blanket piece and instantly killed; his skull was
crushed as though it had been paper and his neck, shoulder, and arm
broken. At Aikawa a blubber strip gave way when half the carcass of a
humpback was suspended in the air, letting the weight of some fifteen or
twenty tons fall upon a cutter standing below; when taken from beneath
the whale the poor fellow could hardly be recognized as a human being.
Kyuquot had trouble, also, when a blanket piece struck a flenser’s
knife, driving it into his side and injuring him badly. And yet it is
surprising what tremendous strength and tenacity the fibrous blubber
has. A few inches of it will resist the strain of several thousand
pounds, and I have seen a whale drag a ship through the water for half
an hour with only two harpoon prongs caught under the blubber of the
back.
When a female whale is pregnant the blubber is much thicker and softer
than at other times and yields a greater supply of oil; from other
causes it may also be very thin, and become hard and dry. The blubber
varies in color and may be light yellow, deep pink, or almost white. It
is thinnest upon the sides, throat, and breast, and thickest on the
“neck” just behind the blowholes, at the dorsal fin, and from that point
along the ridge of the back, or “caudal peduncle,” almost to the flukes.
On the sides an average thickness in the fin whales is six inches, but
just behind the dorsal fin it may reach twelve or fourteen inches.
Since cetaceans live in the water where they do not touch rough surfaces
their skins are very soft and smooth; the skin is about half an inch
thick and may be separated from the blubber only with difficulty. It is
composed of one or more thin outer sheets (epidermis) which may be
easily stripped off, leaving exposed the tender under layer (dermis).
The skin is perfectly dry and does not possess either the oil
(sebaceous) or sweat (sudoriferous) glands usually present in the skins
of land mammals. Because of the development of blubber, and the absence
of functional hair, such glands are no longer necessary. The skins of
some cetaceans, notably the white whale, or beluga, and the bottlenose
porpoise are made into leather and furnish the “porpoise hide” of
commerce, but that of other porpoises or whales has not been put to
extensive commercial use.
[Illustration:
A cross section of the folds on the breast of a humpback whale. The
upper thin black margin is the skin, then comes the thick white
blubber below which is the red flesh.
]
I have often read of ships being followed for days by whales but have no
first-hand information of such occurrences. Scammon, however, remarks
that he has “observed them following in a vessel’s wake for several
leagues,” and gives an extract from the journal of Dr. J. D. B. Stillman
of San Francisco, in 1850, concerning a blue whale, or “sulphur-bottom,”
as it is sometimes called, which followed the ship Plymouth for
twenty-four consecutive days. The account is so interesting that I quote
it in full:
[Illustration:
The eye and ear of a blue whale. The eye is just above the corner of
the mouth and the ear is the small spot about four feet behind it.
The ear canal is just large enough to admit a small pencil, but
because water is such a good medium for carrying sound, whales hear
excellently.
]
November 13th: We are witnesses of a very remarkable exhibition of the
social disposition of the whale. A week ago today we passed several,
and during the afternoon it was discovered that one of them continued
to follow us, and was becoming more familiar, keeping under the ship
and only coming out to breathe. A great deal of uneasiness was felt,
lest in his careless gambols he might unship our rudder, or do us some
other damage.
It was said that bilge-water would drive him off, and the pumps were
started, but to no purpose. At length more violent means were resorted
to; volley after volley of rifle shots were fired into him, billets of
wood, bottles, etc., were thrown upon his head with such force as to
separate the integument; to all of which he paid not the slightest
attention, and he still continued to swim under us, keeping our exact
rate of speed, whether in calm or storm, and rising to blow almost
into the cabin windows.
He seems determined to stay with us until he can find better company.
His length is about eighty feet; his tail measures about twelve feet
across; and in the calm, as we look down into the transparent water,
we see him in all his huge proportions.
November 29th: The bark _Kirkwood_ hove in sight, and bore down to
speak to us. When off a mile or two to leeward, our whale left us and
went to her, but returned soon after. He showed great restlessness
last night; and today, whenever we stood off on the outward tack, he
kept close below us, and rose just under our quarter, and most
commonly to windward, to blow. But whenever we stood toward the land
he invariably hung back and showed discontent. This afternoon he left
us.
It is now twenty-four days since he attached himself to us, and during
that time he has followed us as faithfully as a dog an emigrant’s
wagon. At first we abused him in every way that our ingenuity could
devise to drive him off, lest he might do us some mischief; but save
some scratches he received from our ship’s coppering and numerous
sloughing sores, caused by the balls that had been fired into him, no
damage was received by either of us by his close companionship, though
our white paint was badly stained by the impurity of his breath.
We long since ceased our efforts to annoy him, and had become attached
to him as to a dog. We had named him “Blowhard,” and even fancied, as
we called him, that his came closer under our quarter, when I felt
like patting his glabrous sides, and saying: “Good old fellow.”
As the water grew shoaler he left us, with regret unfeigned on our
part, and apparently so on his. This story of the whale is so
remarkable, that were there not so many witnesses, I would not venture
to tell it, lest I be accused of exaggeration. There were a number of
experienced whalemen among our passengers, who said the animal was a
“Sulphurbottom.”[6]
Footnote 6:
(_l. c._, p. 71, note.)
[Illustration:
The skull of an eighty-foot blue whale, the skeleton of which was sent
to the American Museum of Natural History from Japan. When crated
for shipment the skull had a space measurement of twenty-one tons.
]