Generally speaking, shallow water is dangerous for the larger whales, other than the gray and right whales. Strandings of the other species do occur, which can be interpreted to mean that these whales are not afraid of shallow water. However, when they strand they die. The cause of stranding is difficult to determine. Perhaps the victim is sick and drifts ashore. Most strandings occur during severe storms which quickly obscure the bottom features by stirring up the sand and mud. The stranding of the pilot whale is most dramatic because entire groups will come ashore as if afraid to go back to sea. If man intercedes and helps free them, they still refuse to escape. The cause of the panic and subsequent action is unknown, although it is unlikely that the action is mass suicide as so colorfully described in newspaper accounts. Most other strandings suggest that the whale was out of its normal habitat.
The gray whale, however, has no difficulty in this dangerous region, and in fact they negotiate the treacherous turbid channels of the lagoons, notwithstanding the strong tidal currents which flow through them. They have also been observed rolling in the surf in water barely deep enough to float them. Should stranding occur, they seem to realize that it is only momentary as another swell will come along to free them. For the other species, stranding produces fright and struggling which only exhaust them and lodge them deeper into the bottom. Death usually results from overheating, although it is noted that a stranded whale finds it difficult to breathe normally because the weight of the body out of water crushes the chest cavity.
At the present time it is difficult to understand why the lagoons are used by the gray whale for calving. It may be an ancestral behavior trait which has been inherited. It is most likely, however, that the quiet waters facilitate birth and nursing during the time the baby is gaining strength for the long migration. The observation that the whales may roll and rub themselves against the muddy banks has led to some conjecture that the lagoons help control the skin parasites.
You may wonder whether the lagoons, which are limited in number and in extent, may control the size of the population. Lagoons are subject to change in size and depth through geologic processes, and they may be created or destroyed. The lagoons which are used by the whales are remote and seldom visited by man. You wonder whether the whales would continue to use them if they were also used much by man. The California gray whale has not used San Diego Harbor for over 100 years. Perhaps San Diego Bay was used because the other lagoons were then overpopulated. Certainly the total population of whales has never again reached the numbers which existed before the whalers started.
Scientific Description
It has already been mentioned that the gray whale was described by Professor Cope in 1868-69. The scientific name by which he tagged it, Rhachianectes glauca, describes the fact that the whale is blue-gray in color, and that it frequents rocky reefs. Because the species did not resemble any other whale, he placed it in a separate family, the Rhachianectidae. Cope was not aware that paleontologists had found and described fossils of whales which were very similar to the gray whale. Of course, the paleontologists working in Europe did not know that there was a living representative of these fossil whales which they had named Eschrichtius. However, this oversight was finally realized by Dutch cetologists Van Deinse and Junge, who in 1937 corrected the mistake by placing the gray whale in the genus Eschrichtius, discarding the old genus name Rhachianectes. If you wish to search the scientific literature on the gray whale prior to 1937, you must look for it under the old name Rhachianectes. This is not the first or last time a scientific alias will be produced; yet this one serves to dramatize the fact that the gray whale is truly a living fossil, which is a reminder of some of the evolutionary steps over which the other whales passed to gain the structural and behavioral features needed to occupy the many areas of the oceans.
Infra-red photograph of a gray whale. Note the lingering spout and the blow holes at the forward end of the surfaced whale. Photograph by T. J. Walker.
Reaction to Whaling
The California gray whale is known by other common names, such as “Koku Kujira” of the Japanese, which means “the devil fish.” This indicates the cleverness of the gray whale and the dangers associated with hunting it. Whalers universally considered this species the most difficult to whale and the only one which might charge the boat. Gray whales certainly seemed to learn quickly the dangers to them from whaling. Captain Scammon considered this species the most interesting, giving it top billing in his book on the Mammals of the Pacific Coast. He reports that it was standard practice in the lagoons to kill the baby in order to lure the mother into harpoon range. In these encounters, the whalers showed great courage standing the charge of the angry mother, as they took a chance of losing their boats and their lives. The females of other whale species have a strong maternal instinct, but none of them seems to be so consistently willing to fight for its young as the gray whale.