There are two families of baleen whales in New Zealand waters: Right Whales and Rorquals. Right whales have long, narrow baleen plates and no throat grooves, whereas Rorquals have short, broad baleen plates and many parallel grooves on the throat and chest. Both kinds of whales have paired blowholes and lower jaws longer than upper jaws. Right Whales migrate from Antarctica to temperate waters during the winter, and Rorquals move into tropical and equatorial waters in that season. Right whales inhabit coastal waters while Rorquals are oceanic.
Head of Minke Whale (Balaenoptera acutorostrata). Note numerous throat grooves, baleen plates, and position of blowholes (top centre). Photo: Author
Southern Right Whale
Balaena glacialis australis
This robust whale can be recognised easily by its strongly-arched mouth with long baleen plates, and the lack of dorsal fin and throat grooves. It also has a peculiar calloused “bonnet” on top of the snout and smaller callosities along the edges of the lower jaws. The bonnet is whitish and is often infested with parasitic worms and
Southern Right Whale (Balaena glacialis australis)
barnacles; the remainder of the animal is black in colour. It grows to 60ft but is usually smaller, and travels singly or in small family groups. An 18ft specimen came into Wellington Harbour in 1965.
The Right Whale was highly favoured by early New Zealand whalers (hence the name ‘right’) because it was slow, buoyant when dead, and provided much oil and long baleen. It was hunted almost to extinction and is now protected. Less than twenty specimens have been reported in New Zealand waters over the past forty-three years.
Pygmy Right Whale
The smallest of the baleen whales, the Pygmy Right grows to only 20ft. It has a curved mouth similar to the Southern Right but does have a small dorsal fin. The colour is black and it may have a whitish ventral surface. Only twelve specimens have stranded on the New Zealand coast, and virtually nothing is known about its habits.
Pygmy Right Whale (Caperea marginata)
The skeleton of the Pygmy Right Whale is rather strange in that it has more ribs than any other whale, and the ribs are very flattened. It has been suggested that this skeletal structure enables the whale to lie on the ocean floor without squashing its viscera. The Pygmy Right is known only from Australia, New Zealand and South America, and its rarity has precluded commercial exploitation.
After the Pygmy Right Whale, the Minke Whale is the smallest baleen whale — it grows to about 30ft. The shape of the Minke is similar to that of the Finner but it is relatively stouter for its length. The snout is fairly deep, and there is a small hooked dorsal fin well back towards the tail. The throat grooves stop well short of the navel and in fact hardly pass the level of the tips of the flippers.
The colour is bluish-dark grey dorsally and white on the belly as well on the undersides of the flippers and tail flukes. There is also a white flash under the tip of the snout on each side. The transitional line between dark and light lies about halfway up the
Minke Whale (Balaenoptera acutorostrata)
sides of the body and may be more or less straight or very wavy. The upper surface of the flippers may be almost completely grey, or have varying amounts of white on it.
Thirteen specimens have stranded on the New Zealand coast but the species has not been hunted commercially here. As the stocks of large rorquals in the South Pacific decreases, more attention is being given to hunting the Minke Whale. Because it is one of the smallest baleen whales, there are considerable technical and economic problems involved in using it commercially. Japanese whalers, however, are investigating these problems, and the Minke will probably become an important commercial species before long.
Balaenoptera borealis schlegeli
The Sei Whale has a large, hooked dorsal fin compared to other baleen whales, and grows to about 60ft. The flippers are particularly small, and the throat grooves do not run as far back as the navel. This whale is usually bluish-grey coloured on the back and lighter
underneath. The area of the throat grooves is white, whereas the remaining hind portion of the animal grades into bluish-grey again. The lower jaw is also dark. Occasionally the white ventral area is reduced to a large spot or narrow streak. The undersides of the flippers vary from white to grey and the flukes are light grey. The fine white fringe of the black baleen plates is noticeably silky in texture. Some white plates may occur beneath the snout.
There is only one authenticated report of a Sei Whale having stranded in New Zealand — at Lyall Bay in 1948 — although others
Sei Whale (Balaenoptera borealis schlegeli)
have probably been confused with Bryde's Whale. The Sei Whale spends a short part of the summer in antarctic waters and the rest of the year in the subtropics. It feeds almost exclusively on euphausiid krill, planktonic copepods, and lobster krill. It is now hunted by whalers in the Southern Ocean in place of the protected Blue and less common Fin Whales.
Bryde's Whale is similar to the Sei Whale but is smaller (up to 50ft) and more slender. The dorsal fin is small and pointed, with a deeply concave posterior margin, and the throat grooves run along the whole length of the belly to the navel. This animal feeds mainly on small fishes and its baleen is therefore not fine and silky like that of the krill-feeders. The baleen plates are usually whitish-grey near the snout and black farther back, and they may have a creamy-white band along their inner margin. The whale is coloured bluish-grey dorsally and yellowish-white underneath. The underside of the flippers is grey or white and the tail flukes are dirty white underneath.
Bryde's Whale (Balaenoptera edeni)
In New Zealand, Bryde's Whale seems to be fairly common north of East Cape, and it may make seasonal migrations up and down the northern coast on the way to and from the subtropics. The whaling station at Great Barrier Island caught a number of these whales during 1956-61.
Southern Fin Whale
Balaenoptera physalus quoyi
The Fin Whale is smaller than the Blue Whale, with a maximum length of about 85ft. It is also more streamlined and pointed around the snout. It has a slightly hooked, triangular dorsal fin, and between the fin and tail the back is distinctly ridged — a feature which led whalers to call the Finner ‘Razorback.’ The body is greyish-black dorsally and white on the belly; the undersides of the flippers and tail flukes are also white. The colour of the jaws and tongue are asymmetric, the left side being darker than the right. This is thought to be connected with the way the whales swim on their right side when feeding. They feed mainly on krill, and to a lesser extent on small fishes.
Fin Whale (Balaenoptera physalis quoyi)
The Fin Whale has not been hunted by New Zealand whalers, but like the Blue has been an important species in the antarctic whaling industry. It is occasionally seen by fishermen in Cook Strait, or off the South Island, but the main migration route between Antarctica and the tropics is probably well offshore. There is a fully articulated skeleton of a 55ft Fin Whale on display in the Otago Museum, Dunedin.
Southern Blue Whale
Balaenoptera musculus intermedia
This 100ft giant has a long flattish mouth with jet-black baleen plates, and a long low forehead which fits between the two lower jaws when the mouth is closed. It has up to 100 throat grooves extending backwards beyond the navel, and a low triangular dorsal fin placed well back on the body. The colour is dark slate blue over the head and back, with paler patches sometimes on the sides and belly. The belly is often covered by a yellowish film of diatoms — a feature which gave rise to the early whaler's name for the Blue Whale of ‘Sulphur Bottom.’
There have been eight strandings of Blue Whales on the New Zealand coast, the most celebrated of which was the 87ft specimen which came ashore at Okarito, South Westland, in 1908. After attempts by locals to make a fortune from the carcass, it was flensed on the beach and shipped, with considerable difficulty and hardship for passengers, to Lyttleton via Greymouth and Wellington. The skeleton travelled to its final resting place in the Canterbury Museum by horse and cart.
The Tory Channel whaling station took a few Blue Whales in Cook Strait over the years, but being an oceanic species not concentrating
Blue Whale (Balaenoptera musculus intermedia)
in coastal waters (unlike the Humpback) it was seen only rarely. The Blue Whale was a mainstay of the foreign whaling industry until over-fishing in antarctic waters made protection of the species necessary. Most of the whaling took place in the Southern Ocean close to the polar ice, where the whales spent spring and summer feeding on krill.
The Humpback has the stockiest body of all whales and is easily distinguished by its extremely long flippers, which can be up to one third of the animal's total length. There is a series of knobbly protruberances on the head, jaws, and flippers, which often have large barnacles growing on their summits. The posterior margin of the tail is scalloped and may also have barnacles growing along it.
Humpback Whale (Megaptera novaeangliae)
The colour of this whale is usually black on the back and sides, and white underneath, but some all-black or all-white specimens have been seen.
The Humpback Whale frequents coastal waters — a pair entered Wellington Harbour in 1959 — and is a very spectacular jumper, being able to leap clear of the water. Humpbacks also sometimes swim on their sides with one long flipper standing erect like an enormous fish fin. Intensive hunting by foreign whaling fleets in antarctic waters in the 1950s greatly reduced the stocks of Humpbacks, and by 1963 only 23 were sighted passing through Cook Strait whereas only 10 years previously 500 had been seen in one year. They have been extensively fished by New Zealand and Australian shore-based whalers since the 1840s. Dr W. H. Dawbin
analysed 9000 New Zealand sightings of Humpbacks up to 1955 and showed that the whales had definite migration routes between the Balleny Islands (Antarctica) feeding grounds and the breeding area north of New Zealand. In autumn they travelled mainly up the east coast of the country, with some passing through Cook Strait, and in spring they returned principally by way of the west coasts.
Two Humpback Whales surfacing inside Wellington Harbour in June, 1959. Note spouts, and slightly raised blowholes on left-hand specimen. Photo: N. T. Atkinson.