Smell
The sense of smell is not important to whales, and the organ was abandoned when the nostrils were shifted to the back of the head and modified for diving. Although man may never be able to test whales experimentally for their sensual acuities, it is quite apparent that they are fully aware of their environment. They clearly recognize the environmental signposts which guide them to and from their various areas. Oceanographers are not nearly as adept in knowing where they are on the ocean. Whales clearly recognize their own particular kind, and they do not intermingle. Incidentally, man finds it difficult to differentiate some of the whale species. Because of the rarity of specimens and information, the identity of some species may still be in doubt.
Habits
Filtering whales, unlike the gregarious porpoises and dolphins, seldom school. Even when they appear to be abundant in a limited area, they have congregated for feeding and not for social interaction. Toothed cetaceans, on the other hand, are generally sociable. The sperm whale travels in large groups of females dominated by a single bull whale. The other males have been driven away and the victorious male exercises control of the harem only as long as he wins these contests. Once the dominant male is defeated, he becomes a solitary individual.
Enemies
Killer Whales
Whales, by virtue of their size and speed, are not preyed upon by other animals. The killer whale, however, has the size and inclination. Generally, it is content to capture seals, sea birds, and fishes, and it does not range too far from this prey. There have been isolated reports of killer whales attacking the gray whale. The gray whale is described as being very disturbed whenever a killer whale appears. On the coast of Siberia the gray whale will hide in very shallow water and if cornered is said to go into shock, floating at the surface, stomach up, while the killer whale bites at the tongue and flippers. Perhaps reports like this have been improperly interpreted. It is easy to understand how killer whales would congregate around the catch of the whaler. Recently studies on the loss of hooked tunas from the long-line fishery of the Japanese, show that killer whales are adept at stealing fish along the setline. Additional studies on the natural history of the killer whale must be made before its relationship to other whales can be properly assessed.
Parasites
If whales generally lead a charmed life with respect to predators, they still have their share of parasites both external and internal. Their huge bodies are ideal platforms for the growth of barnacles which have specialized for this unusual habitat. Another very annoying skin parasite is the whale louse, which is a flattish small crustacean which clings by claws to the delicate skin. The digestive tract of the whale provides a wonderful habitat for round worms and tapeworms. Like their host, these parasites are the largest of their kind. Other organs such as the kidneys, liver and lungs are infested too.
Sperm whales suffer from another affliction which is an obstruction of the intestine by a fatty concretion which forms from the bile. Ordinarily these are passed from the digestive tract when small, but if they are retained and continue to grow, an obstruction is possible. The material is a grayish wax which is known as ambergris. It is used by the perfume industry to make permanent blends of various fragrances. Most of this material is obtained by whalers when they process the sperm whale. Only rarely does the material float ashore after the death of the unfortunate producer. Nowadays the value of ambergris is but moderate.