Three or four killers will often combine in an attack upon a large whale, leaping upon it again and again, and striking terrific blows upon its body with their tails, hanging upon its lips like so many bulldogs, biting and tearing its flesh, and often actually killing it. The whale seems terrified by the onslaught of the ferocious creatures, and sometimes scarcely attempts to resist them, apparently knowing quite well that they are sure to be victorious in the end.
The grampus is most plentiful in the northern seas, but is found now and then in almost all parts of the ocean. It occasionally visits the British shores. Once a living specimen was exhibited in the Brighton Aquarium, and did very well for some little time. But one day it got its snout jammed in the rock-work at the bottom of its tank, so that it could not rise to the surface to spout. And when the keeper discovered what had happened to it the poor creature was dead.
The Blackfish
Almost as large as the grampus, but not nearly so savage, is the blackfish, which is so called on account of its color, for it is not a fish, being a member of the dolphin family. It is found in great shoals, generally consisting of two or three hundred animals, and often of a great many more, which are always under the guidance of a single leader. Wherever he goes they will always follow, and they are such stupid creatures that if he swims into shallow water and casts himself ashore, they will all swim after him and fling themselves on the beach also. In Iceland, and also in the Faroe Islands, large numbers of them are often killed, the fishermen arranging their boats in a semicircle between the shoal and the deep sea, and then driving them forward till they strand themselves upon the shore in their efforts to escape. Large herds have also been driven ashore in the Orkneys and the Shetlands.
On the east coast of North America the blackfish is one of the most abundant cetaceans. Off Cape Cod more than a hundred blackfish have been seen in one school, and they are eagerly hunted for the sake of the soft oil yielded by their fat.
Dolphins
There are two groups of dolphins, the first of which contains three animals that live in rivers, and therefore are generally called fresh-water dolphins.
The only one of these that we can mention is the Gangetic dolphin, which inhabits the great rivers of India, and is named from the Ganges. Its chief peculiarity is that it is almost totally blind. Although the animal grows to a length of seven or eight feet, and is bulky in proportion, yet its eyeballs are no larger than peas, while the nerves of sight are so imperfect that it is quite possible that it may not be able to see at all. This is no deprivation to it however, for the rivers in which it lives are always so thick with mud that even if it had properly developed eyes it would be quite unable to use them.
The Gangetic dolphin is very seldom seen, because when it comes up to breathe it only raises just the blow-holes above the surface of the water. For the same reason, we know very little indeed about its habits. But it seems to feed on fresh-water shrimps and mollusks, and also on certain fishes which lie half-buried in the mud at the bottom of the water, rooting about for them with its snout after the manner of a pig. This animal is often known as the susu.
Sea-Dolphins