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New Zealand Whales and Dolphins

Toothed Whales

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Toothed Whales

There are three families of Toothed Whales in New Zealand waters: Dolphins, Sperm Whales, and Beaked Whales. Dolphins are small to medium sized cetaceans (the Killer Whale is the largest at around 30ft), usually with many teeth and a prominent beak, a sharp snout, or a bulging forehead. They are often startlingly coloured with patterns in grey, pink, black, and white. Dolphins are seen frequently near the coast. Sperm Whales have large heads with underslung jaws and single sigmoid-shaped blowholes on the left side of the snout. They are oceanic species which seldom come very close to land. Beaked Whales are medium sized (14-32ft) cetaceans with a long snout arising from either a narrow, smooth head, or a high bulging forehead. They usually have only a few teeth (Tasmacetus is the exception with up to 92), and these are normally functional only in the lower jaws. Beaked whales have a short pair of grooves on the throat and their bodies sometimes show whitish oval scars which are due to bites from a small pelagic shark. They are seldom seen at sea, but appear to be exclusively oceanic.
800lb Bottlenose Dolphin at Marineland of New Zealand Photo: Richard Marshall.

800lb Bottlenose Dolphin at Marineland of New Zealand Photo: Richard Marshall.

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Bottlenose Dolphin
Tursiops truncatus

The Bottlenose Dolphin or Cowfish is one of the largest New Zealand dolphins, reaching a maximum length of 14ft. The beak is relatively short and stout, and there are twenty-three to twenty-five pairs of teeth in each jaw. The teeth are large for a dolphin—about three-eighths of an inch in diameter. The mouthline curves up in a permanent grin—a feature which makes this naturally friendly animal even more likable. There is a high, hooked dorsal fin, the point of which is directed towards the tail. The colour is dark or light grey on the back, grading to white on the belly. The dark colour often sweeps down from the back in a steep curve towards the vent and there is usually a distinct blue-grey band or ‘bridle’ running from
Bottlenose Dolphin (Tursiops truncatus)

Bottlenose Dolphin (Tursiops truncatus)

the base of the beak around the forehead to each eye, and another such band passing up over the forehead to the blowhole.

Tursiops is well known for its playfulness and affection towards man; it is thought to be second only to man in intelligence. Several overseas and one New Zealand (Napier) marinelands have the species in captivity and have found that it adapts quickly to life in a pool, is quick to learn tricks, and is an ideal subject for study. A great deal has been found out about the animal's echolocating capabilities and its social behaviour (including communication). Military interest has been shown in the dolphin's ability to work for and with humans, and a 1971 press report indicates that it has been used to assist divers in the Vietnam War.

In New Zealand Bottlenose Dolphins are commonly seen in the Bay of Islands, outer Hauraki Gulf, and Marlborough Sounds, where they often follow ships. They have been reported to be capable of 20 knots. The famed ‘Opo George’ which mingled with swimmers at Opononi in Northland during the summer of 1955-56 was a female of this species. There are two specimens in the Napier Marineland.

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Risso's Dolphin
Grampus griseus

Risso's Dolphin grows to about 13ft and is fairly deep in the body with a thin tail region. The head has a distinct ‘melon’ — it bulges forward and slopes very steeply down to the mouth. There is no trace of a beak. The Grampus lower jaw is unusual in that it has three to seven pairs of teeth up to half an inch in diameter placed only near the tip of the jaw. In young animals the teeth have recurved tips, but with increasing age they become rounded like .44 bullets. There are usually no teeth in the upper jaw.

The mouth of Risso's Dolphin begins horizontally and then slopes upwards at an angle towards the eye. The flippers are rather long and curved, with pointed tips, and there is a pointed, hooked dorsal fin about halfway between the snout and tail. The colour is grey or brown on the back and flanks, and whitish underneath. The fins and tail are darker than the rest of the body, and the head may be lighter. The body is often covered with scars.
Risso's Dolphin (Grampus griseus)

Risso's Dolphin (Grampus griseus)

Risso's Dolphin is found in tropical and temperate regions of most oceans but seems to be a rare visitor to the South Pacific. It has been recorded only four times in New Zealand. A lower jaw of this species was found on Manawatu Beach in 1867 and a pair of Risso's Dolphins stranded on Orongorongo Beach near Wellington as this article was going to press in 1972. The famous dolphin ‘Pelorus Jack’, which rode the bow waves of steamers passing across the outside of Pelorus Sound and Admiralty Bay, Marlborough, between 1888 and 1912, was also a Risso's Dolphin. There were many curious and conflicting stories written about Pelorus Jack, including some which told of the dolphin's existence as early as the early 1870s, and others which suggested he was an albino outcast that actually sought the company of ships and piloted them across the outer Marlborough Sounds. Pelorus Jack was protected by an Order in Council in 1904 after an attempt was made to shoot the animal from one of the steamers. The dolphin was last seen in April, 1912, and his disappearance was accounted for in various stories ranging from natural death to being harpooned by foreign whalers.

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Dusky And Hourglass Dolphins
Lagenorhynchus obscurus and Lagenorhynchus cruciger

The Dusky Dolphin has virtually no beak, as the head slopes evenly down from the blowhole to the tip of the snout. The mouth slopes up towards the eye and contains twenty-nine to thirty-five pairs of small teeth about one-eighth of an inch in diameter in both jaws. The tip of the erect dorsal fin does not taper to a sharp point, but is rather blunt.

This dolphin is coloured bluish-black on the back and tail, and has a dark band running diagonally across the flanks from below the dorsal fin towards the vent and along the tailstock. The underside of the body is white, and a whitish grey colour extends over the flanks. From the sides of the tailstock two whitish streaks slope up to just below the dorsal fin. The tips of the snout and
Dusky Dolphin (Lagenorhynchus obscurus)

Dusky Dolphin (Lagenorhynchus obscurus)

Hourglass Dolphin (Lagenorhynchus cruciger)

Hourglass Dolphin (Lagenorhynchus cruciger)

lower jaw are dark and a grey area extends from the eye down to the flipper. Sometimes there is a patch of light grey on the sides of the dorsal fin.

The Dusky is fairly common from Hawke Bay south to Fiordland, is attracted to ships, and has been successfully tamed and trained at Napier Marineland. A second species of this genus, L. cruciger or the Hourglass Dolphin, is thought to occur to the south of New Zealand, and may occasionally straggle close to the coast. There have been reports of it to the southeast of the Chatham Islands, but a positive identification from direct examination is needed to confirm its occurrence in our waters.

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The Hourglass Dolphin is similar in shape to the Dusky, but as its name suggests, the colour pattern is different. The animal is dark dorsally and dark pigment extends in a band from around the eye of the flipper, and back along the flanks as a wide patch. Just below the dorsal fin the lateral dark area attenuates and continues to the tailstock as a thin band. The remainder of the animal is white, and the dark patch on the flanks effectively divides the white areas to give an hourglass-like pattern. This is apparently a cold-water, oceanic species, which spends most of its time in antarctic and subantarctic seas.

Striped And Spotted Dolphins
Stenella caeruleoalba and Stenella dubia

The Striped Dolphin, or Euphrosyne Dolphin as it has been called, is similar in shape and colour tonings to the Common Dolphin. It is larger, however, reaching 10ft at full maturity, and has a distinctive colour pattern. Stenella is brownish-black dorsally, becoming lighter towards the tail. The beak, lower edge of the mouth, flippers, and tail are all dark, and there are dark stripes extending from the eyes to the flippers and the eyes to the vent. There may also be a short, light blaze rising from the flanks behind the eyes and curving up towards the dorsal fin. Both jaws contain about thirty-nine to forty-six pairs of small teeth.

The Striped Dolphin was first recorded from New Zealand in the early 1870s, when a specimen stranded at Waikanae near Wellington. The skull and lower jaws of this specimen are still in the Dominion Museum but apparently no information on the outward appearance of the dolphin was obtained. For the next 100 years
Striped Dolphin (Stenella caeruleoalba)

Striped Dolphin (Stenella caeruleoalba)

Spotted Dolphin (Stenella dubia)

Spotted Dolphin (Stenella dubia)

page 30 there were unconfirmed sightings of this species at sea off Northland, and eventually a 6ft specimen washed ashore at Mission Bay, Auckland, in 1971. This animal had, it seems, been shot at sea. The Striped Dolphin probably comes close to the New Zealand coast only in the summer months; it is a warm-water species widely distributed in tropical and temperate seas.

A second species of Stenella, S. dubia or the Spotted Dolphin, may also occasionally stray into New Zealand waters from the north. A skull of this species was found in Golden Bay in 1869. The Spotted Dolphin grows to about 8ft, and has between thirty-eight and forty-five pairs of teeth in the upper jaw and thirty-seven to forty-one in the lower jaw. The colour pattern seems to vary considerably, but is basically dark grey dorsally and whitish ventrally, with an overlay of small light spots on dark areas and dark spots on light areas. It should be easy to recognise in New Zealand waters, for it would be the only dolphin with a spotted colour pattern in the region. This species normally lives near coastal areas and islands in tropical seas, and there may be several geographical races in different oceans.

Common Or Saddleback Dolphin
Delphinus delphis

The Common Dolphin can be recognised by its colour, distinct beak, and low, smoothly-sloping head. Each jaw bears forty-five to fifty-one pairs of small teeth less than one-eighth of an inch in diameter. There is a high dorsal fin, the hinder margin of which may be either weakly or strongly concave. The colour of this dolphin is very distinctive, for basically it consists of a crisscross pattern, with the centre of the cross situated on the flanks below about the middle of the dorsal fin. The dorsal sector of the cross is dark grey or purplish-black and the ventral sector is white; the posterior part is grey (apart from the tail which is dark) and the anterior part is brownish white. The colour pattern of the head is rather complex: the tips of the snout and lower jaw, and the
Common or Saddleback Dolphin (Delphinus delphis)

Common or Saddleback Dolphin (Delphinus delphis)

page 31 ‘lips,’ are purplish-black, and the rest of the beak and jaw is somewhat lighter. There is a patch of black around the eyes from which a bridle extends towards the beak, and there is also a dark blaze tapering from the base of the flipper across the lower side of the head to under the jaw. This blaze is particularly dark in some specimens, particularly large ones which grow to just over 7ft in length. The dorsal fin often has a light patch on its side.

Delphinus frequents coastal waters all around New Zealand and often occurs in huge schools of several thousand individuals. It is a playful animal at sea and has responded very well to training in marinelands here.

Right Whale Dolphin
Lissodelphis peroni

This beautifully streamlined dolphin shares its name with the Right Whale because both are lacking a dorsal fin. It is the only dolphin in New Zealand waters which has no dorsal fin (except perhaps for a stray Black Finless Porpoise), yet despite this easily recognisable character it has only rarely been seen at sea, and only one stranded specimen has been reported. It has a very slight beak which merges smoothly with the head, and each jaw contains forty-three pairs of small teeth. The animal grows to about 8ft and the body is very slender, particularly towards the tail. The colour pattern is most striking: the dorsal surface is jet black, and this colour curves down from the forehead passing between the eye and the corner of the mouth and sweeps up past the flipper towards the back before dipping again and levelling off through to the tail. The rest of the body is white except for the back edge of of the flipper, which is black. When swimming, this dolphin resembles a giant penguin.

The Right Whale Dolphin is probably an oceanic species and may be more common to the south of New Zealand. One specimen stranded on Banks Peninsula in March 1970.
Right Whale Dolphin (Lissodelphis peroni)

Right Whale Dolphin (Lissodelphis peroni)

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Hector's Dolphin
Cephalorhynchus hectori

This dolphin can be recognised at once by its small, rounded dorsal fin — the trailing edge is convex rather than concave as in all other New Zealand dolphins. It is a small dumpy animal growing to a maximum size of 5ft; the flippers are rounded at the tips, there is no beak, and the mouth slopes up towards the eye. There are twenty-seven to thirty-two pairs of small teeth in each jaw.

The colour pattern is complex but distinctive and consists of three well-defined colours, black, grey, and white. The sides of the head, the flipper, dorsal fin, and tail are all black. The tip of the lower jaw is also dark, and there is a thin black line curling over the head just behind the blowhole. The head in front of this line is grey finely streaked with black, and behind it the back and sides of the animal are very pale grey. The belly is white except for the area between the flippers, where the black colour continues down from the sides of the head to meet in a tailward-pointing V on
Hector's Dolphin (Cephalorhynchus hectori)

Hector's Dolphin (Cephalorhynchus hectori)

th ventral midline. There is a grey oval around the genital slit. The white of the belly extends up just ahead of the genital slit, and points back in a long finger-like extension towards the tailstock.

Hector's Dolphin is an inshore coastal species and is often found in muddy or discoloured water seaward of river mouths. It is common around the northern half of the South Island, and has been reported from Kawhia, Hauraki Gulf, and the Bay of Islands. There is one specimen in captivity at Marineland of New Zealand at Napier.

False Killer Whale
Pseudorca crassidens

The False Killer Whale, like the following two species, is really a member of the dolphin family. It grows quite large — up to 16ft in New Zealand waters — and is a slender, well-proportioned animal, with a low rounded snout, smallish hooked dorsal fin, and tapering flippers. There are eight to ten pairs of large, strong teeth up to one inch in diameter in each jaw. Most specimens are entirely page 33
False Killer Whale (Pseudorca crassidens)

False Killer Whale (Pseudorca crassidens)

black, but there may be a blaze of grey spreading from beneath the tip of the lower jaw along the throat to the flippers, where it broadens into a shield-shaped mark which tapers off towards the navel.

This species is found in all temperate and tropical seas and often travels in schools of several hundred. There have been a number of mass strandings of Pseudorca in various parts of the world involving up to 200 individuals. Three mass strandings have occurred in the New Zealand region, including one of 100 animals on the Chatham Islands in 1906.

Pilot Whale
Globicephala melaena

The name ‘Blackfish’ is also applied to this species and it is sometimes confused with the False Killer Whale. It can be distinguished, however, by its very pronounced bulging forehead which may extend several inches ahead of the tip of the upper jaw. There are three further characters which will confirm its identity: the dorsal fin is placed nearer the head than the tail, the flippers are long and sickle-shaped, and the tailstock is vertically flattened. The dorsal fin is very wide at the base, has a low, rounded tip, and deeply concave hind margin. The mouth slants up towards the eye and each jaw contains twenty pairs of teeth about half an inch in diameter, all of which are set near the front of the jaws. Globicephala grows to 28ft.
Pilot Whale (Globicephala melaena)

Pilot Whale (Globicephala melaena)

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The flanks of this animal are a uniform dark brownish-grey colour, which darkens noticeably near the head and on the dorsal fin, flippers, and tail. There may be a lighter patch just behind the dorsal fin, and the edge of the mouth is pinkish. The ventral surface of the body is dark grey anteriorly and lighter elsewhere, except for a wide, sharply demarcated M-shaped area of pinkish-grey just anterior to the flippers. This lighter area merges with the grey of the belly about level with the flippers except for right on the mid-ventral line, where a thin band of pinkish-grey extends down the body to the vent. In young Pilot Whales there is a very fine dark line within the thin band.

There have been many strandings of Globicephala on the New Zealand coast, including several of over 100 individuals.

Killer Whale
Orcinus orca

The Killer Whale is a powerful, solid-looking dolphin which grows to 31ft. The head is fat but pointed and there is a very slight rounded beak. The flippers are big, rounded paddles, and the dorsal fin is very tall (up to 6ft) and sharply triangular. There are eleven to thirteen pairs of large conical teeth in each jaw. The colour pattern is very striking, with distinct black and white areas. The animal is black from the tip of the snout to the trailing edge of the tail, except for a white patch above the eyes and a light grey saddle just behind the dorsal fin. On the underside, the white extends from the tip of the lower jaw through to the tail flukes, and rises up the flanks in a rounded, tailwards-pointing patch just ahead of the genital region.

The Killer Whale is common in New Zealand waters and can often be seen passing through Cook Strait, or entering large harbours such as the Bay of Islands. There have been only six strandings
Killer Whale (Orcinus orca)

Killer Whale (Orcinus orca)

page 35 recorded, including one of seventeen individuals at Paraparaumu in 1955. The Killer feeds on seals and dolphins as well as on the more usual cetacean foods such as fish and squids. It is regarded as potentially dangerous to man, although there are no records of a human having been killed by one of these animals. In fact, a 24ft specimen in the Seattle Public Aquarium, USA, has become quite tame and friendly towards divers in its pool.

Black Finless Porpoise
Neophocaena phocaenoides

In February 1971 an experienced ex-whaler, Mr J. H. Perano of Blenheim saw a strange cetacean swimming with a group of Dusky Dolphins in Cook Strait. It was entirely black and without a dorsal fin, and Mr Perano provisionally identified it as Neophocaena, the Black Finless Porpoise. As Mr Perano is familiar with the Southern Right Whale Dolphin, the only other small cetacean without a dorsal fin, it certainly seems likely that what he saw was indeed a Neophocaena. This is a coastal species ranging from Japan through Asia to the Indian Ocean, and although it has not been recorded from New Zealand before, it is possible that it could stray into the Tasman Sea during a warm summer.
Black Finless Porpoise (Neophocaena phocaenoides)

Black Finless Porpoise (Neophocaena phocaenoides)

The Black Finless Porpoise is a small, stout animal with a rounded, slightly protruberant forehead. There is a depressed area along the midline of the back within which lies a low ridge bearing tiny tubercles. There are fifteen to nineteen spade-like teeth on each side of the upper and lower jaws.

Except for ventral dark grey patches between the flippers and around the vent, the porpoise is entirely black in colour. It is usually a solitary animal.

Any specimens of this species seen at sea or washed ashore around New Zealand should be reported to a museum, so that its occurrence here can be confirmed.

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Sperm Whale
Physeter catodon

This ‘Moby Dick’ of the whales is the largest cetacean to have teeth. The conical teeth grow to about eight inches long and there are usually around twenty-five pairs in the lower jaw. The upper jaw has small vestigial teeth which hardly break through the gums. The Sperm Whale is very distinctive-looking, with its huge box-like head and underslung lower jaw. In place of the normal dorsal fin, there is a series of hump-like ridges along the midline of the back towards the tail. The colour is purplish-brown or dark grey dorsally and grey or white underneath. It grows to about 60 feet.

The blowhole is sigmoid-shaped and is situated on the top left side of the snout — a position which gives rise to the characteristic angled ‘blow’ of sperm whales. Inside the massive head is a barrel-like ‘case’ containing spermaceti oil, a substance once highly
Sperm Whale (Physeter catodon)

Sperm Whale (Physeter catodon)

valued by whalers and used for making medicines and candles. The name resulted from an erroneous notion that the oil was a part of the reproductive system. Sperm Whales feed on squids, octopuses, and fishes, and their bodies are often scarred by the suckers of giant squids.

Sperm Whales were hunted by the Tory Channel Whaling Station in the 1960s in the waters of Cook Strait. Dr D. E. Gaskin studied the Cook Strait Sperm Whale population and found that they were more numerous in summer, and that the fluctuation in numbers was related to the movement of surface water from the warm East Cape current. The water temperatures in summer are favourable for schooling squid, the main food item of local Sperm Whales. He also found that some whales, particularly solitary males, remain in Cook Strait all the year, while the rest move northward about 2° latitude for winter breeding.

Sperm Whales are fairly common stranders on the New Zealand coast and there have been seven mass strandings recorded, involving a total of 175 animals. In March 1970 fifty-nine Sperm Whales stranded at Wainui near Gisborne; this was a typical ‘nursery school’ of females with calves and young adults of both sexes. A ‘bachelor school’ of seven young males stranded at the tip of Farewell Spit in September, 1970, and another nursery school of thirty went ashore on Great Barrier Island in May, 1972.

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Ambergris is a solid, waxy substance secreted in the Sperm Whale's intestine, which has been used in medicines, perfumes, and even as an aphrodisiac. It is sometimes found floating in the sea or washed up on beaches. As a perfume fixative it once fetched $40 an ounce, but is now worth only between 75c and $3 an ounce.

Ambergris looks rather like dark kauri gum but is lighter and much softer. It can be recognised by its dark brownish-black colour and sweet musky smell which is enhanced by warming. A hot needle will melt it into a dark shining liquid which will burn with a luminous flame. Ambergris sometimes contains squid beaks and it is thought to be comparable to the intestinal stones and hair balls found in land mammals.

Pygmy Sperm Whale
Kogia breviceps

This small whale grows to only about 13ft, and its size apart, differs from the big Sperm Whale in having a much shorter head and a short underslung mouth which contains up to sixteen pairs of sharp, backwardly-curved teeth in the lower jaw. Like the big Sperm Whale, the Pygmy has a sigmoid blowhole on top of the head to the left of the midline. The body colour is dark grey or black on the back and whitish-grey with a touch of pink on the belly.
Pygmy Sperm Whale (Kogia breviceps)

Pygmy Sperm Whale (Kogia breviceps)

There have been twenty-three strandings recorded on the New Zealand coast and most have been single animals, although occasionally a cow and calf have come ashore together. Little is known about the biology of these whales, but examination of stranded animals has shown that they feed on squids, shrimps, crabs, and fishes. There is an excellent cast of a 9ft specimen, which stranded at Lyall Bay, Wellington in 1950, on display at the Dominion Museum. An attempt was made to keep a recently stranded Kogia in an aquarium at Napier's Marineland a few years ago, but the animal kept butting its head against the wall of the pool and eventually died. Post mortem examination showed that it was extensively diseased and could not have survived.

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Shepherd's Beaked Whale
Tasmacetus shepherdi

This rare whale has a streamlined dolphin-like body with a long narrowed snout and terminal mouth; it grows to about 30ft. The lower jaw is slightly longer than the upper and contains twenty-seven pairs of functional teeth, the foremost of which are noticeably larger. The upper jaws contain nineteen teeth on each side. This large number of teeth sets Tasmacetus aside from all other beaked whales. There is a small hooked dorsal fin well back towards the tail, and the flipper is small and pointed. The head has only a slight bulge or ‘melon’ behind the beak. The colour is dark dorsally and grey or whitish underneath.
Shepherd's Beaked Whale (Tasmacetus shepherdi)

Shepherd's Beaked Whale (Tasmacetus shepherdi)

Only five specimens are known and all have stranded on the New Zealand coast. The first three came ashore at Stewart Island (two) and Wanganui (one) in 1933, and more recently (1951, 1962) two specimens stranded near Christchurch. Nothing is known about its biology and very little information is available on its external appearance.

Scamperdown Whale
Mesoplodon Grayi

The Scamperdown Whale has a slender body growing to about 12-13ft. It has a small head and pointed beak, with no noticeable bulge on the forehead. There is a hooked dorsal fin well towards the tail, and the ridge of the back between the dorsal fin and tail is sharp. The tail is wide, crescentic, and has no notch. In the
Scamperdown Whale (Mesoplodon grayi)

Scamperdown Whale (Mesoplodon grayi)

page 39 male there is one vertical, triangular tooth in each side of the lower jaw, set well back from the tip. There is also a row of seventeen to twenty-two very small teeth in the upper jaws which are not attached to the gums. In the female, teeth do not emerge from the gums. The colour is dark dorsally and white below, and the head and beak may also be whitish. Sometimes there are small round white blotches on the body.

The Scamperdown Whale is a fairly regular strander on the New Zealand coast, fifty-three having been recorded since 1873. A mass stranding of twenty-five occurred on the Chatham Islands last century.

Hector's And Andrew's Beaked Whales
Mesoplodon hectori and Mesoplodon bowdoini

There is insufficient information on the outward appearance of these two beaked whales in New Zealand waters to enable accurate illustrations to be made. There are skeletons in the Dominion Museum, however, and the diagnostic features of the two species can be illustrated by reference to the lower jaws and teeth (Fig. 7). Hector's Beaked Whale has a small pair of flat triangular teeth almost at the tip of the lower jaw. Andrew's Beaked Whale has a pair of large flattened teeth set in partly raised sockets situated just behind the area where the two lower jaws are fused together (the symphysis). The teeth are convex on the hinder margin and have a small denticle at the tip which projects forwards and outwards.

Both Hector's and Andrew's Beaked Whales are probably fairly small, as the existing skeletons are up to only 14ft in length.

Strap-Toothed Whale
Mesoplodon layardi

This beaked whale is similar in shape to the Scamperdown Whale, but reaches a larger size of about 20ft. The males can be recognised easily by the two strap-shaped teeth set back from the tip of the jaws and tilted backwards at an angle of approximately forty-five degrees. As the whale grows, the teeth curve over the upper jaw
Strap-Toothed Whale (Mesoplodon layardi)

Strap-Toothed Whale (Mesoplodon layardi)

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Figure 7: Lower jaws and teeth of New Zealand Beaked Whales. Arrow marks position of hind margin of symphysis.

Figure 7: Lower jaws and teeth of New Zealand Beaked Whales. Arrow marks position of hind margin of symphysis.

page 41 eventually preventing the mouth from opening completely. These strange teeth are thought to act as ‘guide rails’ to keep squids and fish on the right path towards the throat. The teeth of females are hardly developed, making identification difficult without close examination of the skull bones. The colour of the body is black or dark grey above, and paler, sometimes with yellowish tonings, below.

Despite the fact that over twenty Strap-Toothed Whales have stranded on the New Zealand coast, hardly anything is known about the biology of this species.

Cuvier's Or Goose-Beaked Whale
Ziphius cavirostris

The body shape of this whale is similar to that of other beaked whales but the head is not narrow and pointed, and the beak is relatively short, particularly in the male. The mouth is decidedly curved upwards and there is one pair of big sharp teeth at the tip of the lower jaw which protrudes in front of the upper jaw. Up to thirty-four small vestigial teeth are present in the gums of the upper jaw. In the female, all the teeth are hidden within the gums. In contrast to other beaked whales, this species has a slight median notch in the tail.
Cuvier's or Goose-Beaked Whale (Ziphius cavirostris)

Cuvier's or Goose-Beaked Whale (Ziphius cavirostris)

The Goose-Beaked Whale grows to a maximum size of 32ft, but animals in the 20-25ft range are more common around New Zealand. The colour is variable, but seems to be either grey, fawn, or purplish-black on the back and lighter on the belly and around the head. The body may also have white oval blotches and scars.

There have been a number of strandings of this species around Bank's Peninsula and the Golden Coast north of Wellington. In Hawke Bay recently a specimen was saved from stranding and assisted back to sea by Alex Dobbins of Marineland of New Zealand.

Large Beaked Whale
Berardius arnouxi

This species grows to 32ft and is a heavy, robust animal with a prominent beak and bulging forehead. The lower jaw extends page 42
Large Beaked Whale (Berardius arnouxi)

Large Beaked Whale (Berardius arnouxi)

several inches beyond the upper jaw and it has two pairs of teeth near the tip, the front pair being the largest. Once again, teeth may not emerge in the female, and skull characters need to be checked for positive identification. The whale is dark coloured — black or grey — on the dorsal surface and lighter on the ventral. Virtually nothing is known about its biology but it is thought to feed on squids.

There have been nineteen strandings of this species recorded in New Zealand, mostly around the Cook Strait area during summer.

Southern Bottlenose Whale
Hyperoodon planifrons

The Bottlenose Whale is very rare in New Zealand waters, its occurrence here being based on the fragments of two lower jaws found near East Cape and Timaru, respectively. The species has stranded in Australia however, and the following description is based on the Australian records. The body is solid, the tail flukes are wide, and there is a distinct beak protruding from a very bulbous forehead. The forehead actually slopes forward to overhang the base of the beak. There is one pair of short, conical teeth situated at the tip of the lower jaw sloping forwards and slightly outwards. Each tooth has a central, peaked denticle.

The whale grows to about 25ft and is bluish-black on the back and creamy-grey on the belly. It probably feeds mainly on squids. A closely-related species in the northern hemisphere is known to dive to great depths in search of food, and it is thought that the massive, fatty forehead acts as an acoustic lens for directional beaming of echolocation signals.
Southern Bottlenose Whale (Hyperoodon planifrons)

Southern Bottlenose Whale (Hyperoodon planifrons)