SPECIES OF MAMMALS OF THE PACIFIC AREA 129 Fig. 52 — Hump-hacked Whale of finback whales are smaller, from twenty-five to sixty-five feet in length.
Finbacks are slender of body, with a dorsal fin ; the head is one-fourth or less of the total length, and the "muzzle" is broad rather than deep. The throat and breast have numerous longitudinal folds, and the whalebone is short and coarse. Finbacks are found in almost all seas, but they are commoner in the cooler waters than in the tropics. These whales are the species now hunted commercially, most of the others being too rare to be profitable.
Toothed Whales, Dolphins, and Porpoises Suborder Odontoceti Adult toothed whales always have teeth, but in some cases these are not functional. The teeth are usually numerous and peg-like, and the nostrils open by a single blowhole. The small toothed whales with long, pointed "beaks" are usually called dolphins; those without "beaks" or with small, rounded ones, and with bulging "foreheads" are called porpoises. The Sperm Whale (Physeter) reaches a large size ; the males are as long as eighty-five feet, but the females are much smaller. The head occupies almost one-third of the total length. The upper jaw and muzzle are barrel-shaped ; the lower jaw, bearing the teeth, is slender and pointed. The spout is directed diagonally forward and is "slow." Sperm whales are often found in
130 MAMMALS OF THE PACIFIC WORLD schools of fifteen or more (once schools of a hundred were not uncommon), and they feed on squid, octopus, and some kinds of fish. Although these whales are commonest near the equator all across the Pacific, they are found also between fifty degrees south latitude and forty degrees north, with concentrations off New Zealand and Australia, and between Hawaii and Japan. Fig. 53 — Sperm Whale Ambergris, a substance used as a base for perfumes, is a product of the sperm whale, formed in the digestive tract. It is usually grayish in color, with a sweet, slightly musty odor. It is so valuable that for months after some has been found, bits of waste fat or soap, mistaken for it, are hopefully brought to museums for identification.
The Pygmy Sperm Whale (Kogia) is much smaller than the sperm whale. It attains a length of about twelve feet. The head is short and rounded and a dorsal fin is present. It is found in all seas, but seems to be rather rare. The Bottle-nosed Whale {Hyperoodon) is about twenty-five to thirty feet in length when fully grown. Its body is rather heavy; the "forehead" bulges, and there is a well-developed "beak." In color this whale varies from dark gray to black above and lighter on the underside. There are only two small teeth, situated one each side at the tip of the lower jaw and hidden in the gums. The bottle-nosed whale is known to occur off the west coast of Australia; records in the islands to the north are lacking.
The Baird Whale (Berardius) is rare. It is found from the Bering Sea to California and may occur off Japan. A second
SPECIES OF MAMMALS OF THE PACIFIC AREA 131 species is reported from near New Zealand, but not elsewhere in the southern Pacific. Both species have two large teeth, roughly triangular in shape, one on each side of the lower jaw. Dorsally they are black with the underside whitish, gray, or flecked with black. They have a well-developed forehead and a long and heavy beak. The northern species reaches about thirty feet, the southern about forty.
Cuvier's or Goose-beaked Whale {Ziphius) is about eighteen feet in length. It varies above from black to gray or even white, at least on the foreparts. A single pair of teeth is present, situated near the tip of the lower jaw. It is recorded from off Australia, New Zealand, and Java.
Typical Beaked Whales (Mesoplodon) of several species occur in Australian and New Zealand waters ; another is found from the Bering Sea to California and may be expected in Japanese waters. All species have a single pair of teeth in the lower jaw; in some species these teeth are sometimes large and situated about the middle of the jaw, and in other species they are poorly developed and placed near the tip. Beaked whales are from ten to twenty feet long, depending on the species ; the beak is long and the forehead poorly developed. The Killer Whale (Orcinus) is black in color, with distinctive white markings on the underparts and sides. The dorsal fin is large, situated near the middle of the body, and the flippers are broad and paddle-like. Killers are twenty to thirty feet long and have from ten to twelve large conical teeth on each side of the upper and lower jaws. They are found in all seas. They feed normally on large fish, smaller dolphins, and seals. Occasionally they form packs like wolves to attack larger whales and may be dangerous to a ^person in the water. The Gray Porpoise or Risso's Dolphin (Grampus) has a high, sickle-shaped dorsal fin, much like that of the killer whale. It is only about ten feet long, however, and grayish in color, with a pale head. It has hardly any beak ; the front of the head rises almost vertically from the tip of the upper jaw and the forehead bulges. The flippers are long and narrow. Risso's
132 MAMMALS OF THE PACIFIC WORLD dolphin is found near the coasts of New Zealand and eastern Australia and in the northern Pacific, from California and Japan to the Aleutians.
The False Killer Whale (Pseudorca) is completely black and more slender in shape than the killer. The long and tapering flippers comprise about one-tenth of the body length. The short dorsal fin is directed backward. Eight to eleven pairs of large teeth much like those of the killer in appearance are found in both jaws. Cuttlefish or squids are the chief prey of this porpoise. The false killer is twelve to fourteen feet in length. It lives in all seas.
The Irrawaddy Dolphin (Orcella) is about seven feet long. The short head has a bulging forehead and narrow, shelf-like beak. The color is slaty blue. The teeth number twelve to nineteen on each side of the upper and lower jaws. This dolphin feeds on fishes. It is found in the Straits of Malacca and Macassar and near the shores of the South China Seas. The Blackfish or Pilot Whale (Globiocephala) is almost world-wide in distribution. The head is greatly swollen in front, the forehead bulging out above the upper jaw. These whales are about fifteen to eighteen feet in length. The teeth, ten on each side, are located at the front of the jaws. Blackfish live for the most part on squid. Large schools of blackfish occasionally beach themselves without obvious reason. Ball's Porpoise {Phoccenoides) has no beak. The body is black, with a large white area on the underside extending to the sides of the hinder half. The teeth are small ; twenty-three are found in the upper jaw and twenty-seven in the lower on either side. This porpoise is found in Alaskan waters south to California, and True's porpoise, a closely related species with the white marking covering most of the sides, is found off Japan. The Harbor Porpoise (Phoccena) slate gray and less than six feet long, occurs along the North Pacific shores. The Finless Black Porpoise (Neomeris) is found from the coasts of southern Japan and Formosa to the Cape of Good
SPECIES OF MAMMALS OF THE PACIFIC AREA 133 Hope and is fairly common in the Malay region. It is about four and one-half feet long, with a bulging forehead, and has from fifteen to nineteen pairs of teeth in each jaw. Right Whale Dolphins (Lissodelphis) were given this name because they have no dorsal fin and thus resemble the right whales. They are small — six or eight feet long — slender, and have a distinct beak. The southern species, found near New Zealand and southern Australia, has a black back and white lower parts, the white including the beak. The northern species, found in the Pacific from California northward, is black, excepting a white area on the breast and a stripe of white extending from this region to the tail. The right whale dolphins have many small teeth : forty-three on each side of the upper and lower jaws in the southern species ; forty-four pairs in the upper and fortyseven pairs in the lower jaw of the North Pacific form. The White-headed Dolphin (Cephalorhynchus) is one of the common New Zealand species. Its body is light gray, with the nose and forehead pure white, gradually passing into the color of the body. It is about four feet long and has thirty-one or thirty-two teeth on each side of the upper and lower jaws. Another species, Hector's dolphin, from the same region, has the beak more developed. Its upperparts are blackish, its underside white, and a narrow band of white extends back on the sides toward the tail. It is about six feet long and has about thirty pairs of teeth above and below. Related species are found in the waters off the Cape of Good Hope and the southern tip of South America.
Several species of the genus Lagenorhynchus are found in the Pacific. They have high, sickle-shaped dorsal fins, not unlike those of the killer whale and Grampus, and the beak is usually poorly marked. The white-sided dolphin of the North Pacific Ocean is black above, with an irregular white area on the side, which comes up about to the level of the eye. The flippers are black. This dolphin is about seven feet long, and has twenty-seven teeth on each side of upper and lower jaws. The
134 MAMMALS OF THE PACIFIC WORLD hour-glass dolphin is five or six feet in length and has a distinct, though short, beak. The white markings on the sides consist of two torpedo-shaped areas, one from above the eye tapering back to the level of the dorsal fin and the other from the base of the tail tapering forward to join or almost join the first. The flippers are black and so is an irregular band from the eye to the tail separating the white of the sides from that of the underparts. The white areas of the sides are connected in front of the eye. This species is found in the southern Pacific. The dusky dolphin of New Zealand and the Falklands has a longer beak than its relatives. The white of the underside extends up on the side to about the level of the eye, and there is a whitish marking on the rear part of the dorsal fin. The back is dark brown. This species is common in the seas around New Zealand. Another species, very poorly known, is reported from the tropical Pacific, but it is known only from the skull. Bottle-nosed Dolphins (Tursiops) have high, sickle-shaped dorsal fins, a rather heavy body, swelling forehead above a short beak, and the lower jaw longer than the upper. The upperparts are gray or blackish, the underside white. One species in Australian waters has the sides, lower surface, and flippers covered with dark blotches. Other species lack these blotches and are found in all temperate and tropical seas.
The Common Dolphin (Delphinus) has a narrow, relatively long beak (five to six inches) that is sharply marked off from the forehead by a V-shaped groove. The body is black or dark gray, and on each side are undulating bands of whitish, yellowish, or gray ; the eye is circled by a ring of blackish and a line connects this with the snout. The upper and lower jaws bear forty to fifty pairs of fine teeth. The common dolphin is about seven and one-half feet long. It is found almost throughout the world. A small, closely related species is the red-bellied dolphin ( D. roseiventris) found in the Banda Sea and Torres Strait. It is stouter in build, and about three feet ten inches in length.
SPECIES OF MAMMALS OF THE PACIFIC AEEA 135 Fig. 54 — Common Dolphin The Long-beaked Dolphin (Steno) has a beak even longer than the common dolphin and distinctly marked off from the forehead. The teeth, twenty to twenty-seven in number, are heavier than in the common dolphin and are roughened or furrowed. The upperparts are blackish or deep gray, while the underside is white. This slender species measures about eight feet in length. The long-beaked dolphin is recorded from the Malay Archipelago, but not elsewhere in the East Indies. The Slender Dolphins (Prodelphinus) are shaped like the long-beaked dolphin but the teeth, which number thirty-nine pairs in each jaw, are smooth. They differ from the common dolphin (Delphinus) in having the palate flat, without the deep grooves inside the toothrows found in that species. The slender dolphin of the waters of the East Indies is ashy gray. It is about six feet long. It may reach Japanese waters, but the limits of its range are not known.
The White Dolphins {Sot alia) of the Malay waters and Chinese coast have long beaks ; the flippers are broad at the base and have the posterior margin concave. The Malay species is glossy white with gray dappling and has about thirty-seven teeth in each row. The Chinese species may occur off Formosa. It is milky white, with pinkish fins, and has thirty-two teeth on each side above and below. A slaty-colored species, sometimes called the lead-colored or plumbeous dolphin (S. plumbea), is distinguished by its very long snout ; from the tip of the snout
136 MAMMALS OF THE PACIFIC WORLD to the eye is about one-sixth of the body length, which is about eight feet. The number of teeth is about thirty-five on either side above and below. It is found from India to the Straits of Malacca.
DuGONGS, Sea Cows. Order Sirenia The sea cows, manatees, and dugongs are mammals which have undergone almost as much change to fit them for an aquatic life as have the whales. Their hind limbs have disappeared, their fore limbs are now flippers, their tails have expanded into flukes. In some of their features they resemble the elephants. The upper incisors when present have developed into tusks. The cheek-teeth come into place from the back of the toothrow, pushing the others forward as they wear. DuGONG. Family Dugongid^ The Dugong (Dugong dugong) is the only representative of this family. This animal has a crescent-shaped tail. The upper incisors of the males are enlarged to form small tusks ; in the female these are yet smaller and do not pierce the gum. Fig. 55 — Dugong In color, the dugong is uniform bluish gray, sometimes lighter on the underside. It may be as much as nine feet in length although it is generally smaller. The dugong feeds on seaweeds and other aquatic vegetation and lives in shallow bays and estuaries from the Red Sea through the Indian Ocean and east as far as the Solomon and Marshall Islands. It extends south