The Animal World, A Book of Natural History Part 16

It is owing to this singular method of breathing that whales can be so easily killed. The object of the hunters is simply to drive them below before they have finished spouting. They do this again and again, and the consequence is that the poor animal soon becomes completely exhausted and falls an easy prey.

THE WHALE'S BLUBBER

You remember, don't you, how the seals are protected from cold, partly by their thick and oily fur, and partly by the layer of fat which lies just under the skin? Well, the whales are protected in much the same way. They have no fur, of course; but the layer of fat, which we call blubber, is always several inches in thickness, and is sometimes as much as two feet; so that the whale is never chilled by living in the water, even when it has to make its way through floating ice.

This blubber has another use as well. When the whale dives to a great depth--and sometimes it sinks half a mile or more beneath the surface of the sea--the pressure on its body becomes enormously great because of the weight of the water above it. If you were to dive to half that depth you would die. But the blubber of the whale is so elastic that it resists the pressure just as a great thick sheet of india-rubber would, so that the animal does not suffer from it in the least.

MISTAKES OF ARTISTS

Sometimes you see pictures in which whales are drawn with very big eyes, very long ears, and perhaps even with their tongues hanging out of their mouths. Now such pictures are drawn by artists who know nothing about whales, for the eyes of these animals are quite small, their outward ears are merely little holes in the skin, closing by means of self-acting valves like those of the seals, and the tongue cannot be poked out of the mouth at all.

Now let us learn something about the different kinds of whales.

TOOTHED WHALES

First come the toothed whales, or denticetes. As an example of these we will take the famous sperm or spermaceti whale, which is also known as the cachalot.

This whale has nearly all its teeth in the lower jaw, the upper one only having a very short row of small teeth on either side. The lower teeth are five or six inches long, and fit into pits in the upper jaw when the mouth is closed. These teeth are composed of beautiful ivory, and were formerly valued so highly by the natives of the South Sea Islands, that more than once a tribe has actually gone to war with another tribe simply to obtain possession of a single whale's tooth.

Now that it has been hunted so much, apparently the sperm-whale does not grow to so great a size as it did in days gone by. Yet it is a very big animal, for a full-grown male will attain to a length of sixty or even seventy feet, while even a baby whale is from eleven to fourteen feet long, or as big as a big walrus. And, strange to say, the head is almost as large as the body and tail put together. This is chiefly due to the fact that there is a great cavity in the skull, which contains the valuable substance we call spermaceti. When one of these whales is killed, the head is cut off, and a kind of well is dug in the forehead, from which the spermaceti is drawn to the surface in buckets, as much as thirty barrels being sometimes taken from a single animal.

Besides this, the blubber yields a large quant.i.ty of very valuable oil, which burns with a much clearer and stronger light than ordinary whale-oil. And sometimes a curious substance called ambergris is found in its body. It is used in making certain kinds of scent, and is quite costly, although as much as fifty pounds of it have sometimes been taken from a single whale.

Sperm-whales are generally seen in companies, which are known as schools. In olden days there were sometimes as many as two hundred whales in one of these schools. But so many of the great creatures have been killed by whalers that it is now quite the exception to see more than four or five together.

These whales are very playful creatures, and may often be seen gamboling on the surface of the sea, and now and then breaching, or leaping completely out of the water and falling back again with a tremendous splash. They feed chiefly upon the great cuttles, or squids, which are so plentiful in some parts of the ocean, but also devour large numbers of cod and other fishes. But how they manage to catch these fishes n.o.body quite seems to know.

These whales were formerly hunted by means of a small boat, in the bow of which stood a man with a long spear, or harpoon, in his hand, attached to an enormous coil of rope. As soon as this was hurled at a whale the boat was backed, so as to escape the stroke of its tail, and the whale would then sound, or dive to the depth of perhaps three-quarters of a mile. As soon as he rose he was driven down again, as already described, before he had had time to finish spouting, and at last, when quite exhausted, was killed by means of a very long and sharp-edged lance. Nowadays, however, the harpoon is generally fired from a ship by means of a gun, and as a charge of gun-cotton is placed in the harpoon's head, which explodes as soon as the weapon enters the body of the whale, such a severe wound is caused that the animal very soon dies.

BOTTLE-NOSED WHALES

These whales are so called because their muzzles are produced into beaks shaped somewhat like bottles. Although they belong to the toothed whales they only have two teeth in the lower jaw, and even these are so small that they are completely buried in the gum.

By the side of the cachalot the bottle-nosed whale seems quite a small animal, for even the full-grown male seldom exceeds thirty feet in length, while the female is quite six feet shorter. It yields, on an average, about two hundredweight of spermaceti and two tons of oil. Its color, strange to say, is continually changing all through its life, for the young animals are black above and the older ones brown, which grows lighter and lighter as time goes on, till at last it becomes almost yellow.

These whales seem to be very sympathetic creatures, for if one of them is wounded, its companions generally swim round and round it, and will even allow themselves to be killed one after the other rather than take to flight. But they are also rather stupid animals, for if they happen to find themselves near the coast they seldom seem to realize that they can easily escape by turning round and swimming out to sea, but leap and tumble about in a state of great terror till at last a big wave comes and throws them up on the beach.

WHALEBONE-WHALES

The members of the other great group of these animals are called whalebone-whales, because they have whalebone in their mouths instead of teeth.

Of course this substance is not really bone at all. It consists of a kind of h.o.r.n.y material which grows all round the upper jaw in a series of flattened plates, which are usually very long, and hang downward from the edge of the palate. Each of these plates, at the tip, is broken up into a sort of hair-like fringe; so that when the jaws are partly closed there is a kind of sieve, or strainer, between them, through which everything must pa.s.s that goes in or out of the mouth.

This sieve is used in feeding. It seems strange that an animal so huge as a whale should feed on some of the smallest creatures which live in the sea. Yet such is the case, for the throats of the whalebone-whales are so narrow that one of them would almost certainly be choked if it tried to swallow a herring. So these whales live upon very small jelly fishes, and the young of shrimps, prawns, tiny crabs, etc., which often swim about in such vast shoals that for miles and miles the sea is quite alive with them. When the whale meets with one of these shoals it opens its mouth wide and swims through it. Then it partly closes its mouth, and squirts out the water which it has taken in through the whalebone strainer, the little animals, of course, remaining behind. These are then swallowed, a few thousand at a gulp, and the whale opens its mouth and repeats the operation over and over again, until its enormous appet.i.te is satisfied.

Most of the whalebone which we use is obtained from the bowhead, or Greenland whale, which is found in the northern seas. This animal is from forty to sixty feet long when fully grown, and the baleen plates are often ten or even twelve feet in length, while there are nearly four hundred of them on each side of the upper jaw. In a large whale these plates weigh more than a ton, and are worth at least $15,000. Then from 130 to 150 barrels of oil will be obtained from its blubber; so that a big Greenland whale is a very valuable animal.

But whales of this size are now very rarely met with, and there seems to be some danger that before many years have pa.s.sed away these giant creatures will be almost extinct.

RORQUALS

The rorquals are sometimes known as fin-whales, or finbacks, because they have an upright fin on the hinder part of the back. They are not so valuable as the Greenland whale, because their baleen is of inferior quality, and is very much shorter, while their blubber does not yield nearly so much oil, and they can swim with such speed that they are very much harder to catch.

The common rorqual grows to a length of about sixty or sixty-five feet, and is found throughout all the northern seas, and occasionally even in the Mediterranean. It is a solitary animal as a rule, but schools of from ten to fifteen individuals are sometimes met with, and may be seen leaping into the air, and rolling and tumbling about in the water, as though they were having a game of play together.

The rorqual feeds partly upon the small creatures which it captures by means of its whalebone strainer, and partly upon fishes. How vast its appet.i.te is you can judge from the fact that as many as six hundred large codfish have been found in the stomach of one of these animals, together with a number of pilchards. Sometimes a rorqual will come quite near the coast, and remain in a fishing-ground for weeks together, and as it swallows several boatloads of fish every day, it is scarcely necessary to say that the fishermen are not at all pleased to see it.

There is another kind of whale, called the lesser rorqual, which only grows to the length of about twenty-five or thirty feet. It is common off the sh.o.r.es of Norway, and commoner still in North American waters, where it is known as the sharp-nosed finner. It is a very playful animal, and is said sometimes to gambol round and round a ship for miles, now and then diving underneath it on one side and coming up on the other.

[Ill.u.s.tration: TYPES OF BEARS.

1. Polar or Ice Bear. 2. American Black Bear.

3. Brown Bear: Grizzly Bear. 4. A Marine Bear (California Seals).]

THE DOLPHIN FAMILY

Next we come to the dolphin family, which includes the narwhal, the grampuses, and the porpoises, as well as the true dolphins.

THE NARWHAL

This is a curious animal, for the male has a very long straight tusk projecting from one side of its upper jaw. This tusk is often as much as seven or eight feet in length, and the ivory of which it is made is twisted round and round in a spiral from base to tip. In former days this tusk was thought to be the horn of the unicorn, and the narwhal is often known as the sea-unicorn.

In reality, this tusk is the left-hand upper "eye" tooth of the animal, that on the right-hand side being very small and completely buried in the bone of the jaw. Now and then, however, both teeth are developed, and a narwhal was once killed which had one tusk seven feet five inches long and the other seven feet. There are no other teeth in the mouth, and the female animal has no tusks at all.

Now what is the use of this singular weapon? Two or three answers have been given to this question. Some people have supposed, for example, that it is used in spearing fish, or in digging up buried mollusks from the mud at the bottom of the sea. But the female narwhals require food just as much as the males do; how is it that they are not provided with tusks also?

Other people have thought that when the winter is very severe, and the ice on the surface of the sea is very thick, the animal could bore a hole through it with its tusk, and so be able to breathe. But then again, female narwhals require air just as they require food. So this suggestion will not do either.

The only explanation we can really give is that the narwhal's tusk is a weapon used in fighting, just like the antlers of the male deer. At any rate, narwhals have several times been seen as they were taking part in a kind of make-believe battle, and striking and clashing their tusks together just as though they were fencing with swords. And when they are fighting in earnest they must be able to use their long spears with terrible effect, for several times a narwhal has charged a ship, and driven its tusk so deeply into her timbers that it was quite unable to withdraw it.

The ivory of which this weapon is made is of very fine quality. But as the tusk is hollow for the greater part of its length it is not very valuable.

Narwhals are only found in the half-frozen seas of the far north, where they are sometimes seen swimming side by side together in large companies. They grow to a length of twelve feet or over, and are dark gray in color on the upper part of the body, and white underneath, the back and sides being more or less mottled with gray.

THE WHITE WHALE

The white whale, or beluga, is something like a large narwhal without a tusk, and is also a dweller in the northern seas. But it often ascends the larger rivers for hundreds of miles in search of fish. Now and then it has been killed off the coasts of Scotland, and one example lived for quite a long time in the Firth of Forth, going up the river day after day as the tide came in, and always retreating as it began to fall. The fishermen were very anxious to kill it, because of the quant.i.ties of fish which it devoured. But it was so quick and active that it eluded them over and over again, and three whole months pa.s.sed away before at last they succeeded.

In one or two of the great rivers of North America white whales are regularly hunted, the animals being first driven up the stream, and then caught with nets as they return. They yield a large quant.i.ty of very pure oil, and the "porpoise-hide," which is used so largely in making boots and shoes, is in reality prepared from their skins.