GREAT WHALES

Hokitika Guardian, 1 July 1930, Page 2

GREAT WHALES

(By J. DRUMMOND, F.L.S., F.Z.S.)

Difficulties in observing the liahits cf Avhales are obvious, but in vieiv of the dimension o’f the wlialing industry much more precise knoAvJedge of these great mammals of tlie sea might be expected than is possessed. Whalers mostly, are intent oil’ their Avork. If some Aiitli inquiring minds study whales from any but the utilitarian point of vieAV, they are reluctant to put their knowledge on paper and print it. Mr Frank Rutllen Avas an exception, but even bis “Voyage - of the Cachelot” ranks chiefly as a delightful story of experiences. For these reasons the Avorld av i 11 Aielcome a large volume on whales in the set of Discovery Reports issued by the Discovery Committee, London, and published by the Cambridge University Press in the 'ignified style that characterises all its Avork.

This Discovery Expedition Avas sent to the dependencies of the Falkland Tsismls to gather information on Avhales and on factors tliat influence them. It built at South Georgia a laboratory, at which observations AA’ere recorded. This expedition, by the' wav, was given its title because it bought the yessel that mnde a stir in :New • Zealand almost thirty years ago, when Captain Scott and v his National Antarctic Expedition mnde Lvttelton the hendounrters oi p one of the most dnring exploits m his torv. Refitted for hew A\ 7 ork in southern latitudes on the other -side of the earth. Captain Scott’s vessel Avas commissioned as the Royal Research Ship Discovery,

Whale,s t in the first place excite admiration by their prodigious size in these days of small things compared with lumbering creatures of the past. In Genesis they are described in tiie simplest term as great Avhales. The blue' Avbale which Avas Avas,lied ,ashore at OkaritOjC South Westland, and Avhose skeleton is in Canterbury Museum, once field the record as the greatest of them all, Avith a length in a straight line not over the curves of the body, of. eightyseven feet. A blue AA 7 hale. caught by the Discovery Expedition at South Georgia was 95ft 6in long . The Norwegian Whalers’ Association has described five Avhales < 100 feet 1 pv more long. These measurements seem to, be unreliable. Still, 100 feet is not an improbable length for a blue . -whale. The largest fin Avljale caught at So\ith Georgia Avas 80ft oin long. , _

Blue whales and fin AA 7 hales caught at South Georgia seem to live almost’ exclusively on a luminous, shrimp, aptly named Euphausia,.superba, which has highly developed luminous organs’ equipped Avith n lens, a reflector, and light-producing tissue . These bull’s eye Interns are used by; their oAA'ners -for lighting, up the Avaters. brilliantly. In the stomachs, of South Georgian AA'hales hardly any other food Avas 'found. There Is no need for those Avhales to want for foo.cji as . m parts of the Antractic and sAib-Antnrctic wateps EuphniAsia superba flourish In countless numbers. They, gather Tn dnse shoals near the land, and the richest feeding-grounds of the southern AA’liales are in places like the dependencies of the Falkland Islands. Usually, the Avhales’ stomachs Avere well filled Avith fresh shrimps. An ’empty stomach Avas uncommon.

The calf of a blue whale is about 23ft' long when born, the calf off a fin whale about 21ft. The time of gestation is slightly over ten months with blue whales, and eleven month and a half with fin whales. Weaning takes .place when a baby blue whale is about 45ft long. Fin whales are much smaller when they are weaned. In blue whales, the nursing time is about seven months. After weaning, the rate of growth slows down. The "rent sizes of blue whale and fin whales give an impression that they must need an exceptionally long time to grow to maturity, and must live to a great age compared With other creatures. .It has been shown that growth is> ; surprisingly rapid during gestation and adolescence, and that one of these whales becomes an adult in an unexpectedly short time.

No direct menus has been found yet to determine' the age of any individual ■iVhale, but-it is possible sometimes to judge if one whale is older or younger than another. With younger whales there are grounds for guesses at their actual ages. Size is a rough criterion up to a point. There is renson to believe that when a whale reaches a size-at which it should be an adult, >. is about two years of age. A female fin whale 65ft long probably would not he more than three years, hind.one 78ft probably would not be ■ Mss than four years. Beyond this, it is impossible to go at present. An important economical point disclosed by these studios is that whales actually engaged in pairing are not much molested by whalers at South Georgia, the whales migrating to other parts to nair. Pairing seems to take nhace far from land, or at learht. outside of the range of the land stations. Against this and in preserving the race, onlv one whale is horn at a time, and a female can, at most, produce only one young every two years. The rate of reproduction is very slow. This, again, is counterbalanced to /some extent by the fact that a young whale can reproduce its kind in about

two years after birth. Some habits of the blue whale and of the fin whale favour survival of the race. Others are serious weaknesses 'from that point of view.

These papers do not recommend any definite measures by which the whaling industry should be adjusted, biit they bring forward facts and inferences from the biology and habits of whales that bear on the effect of hunting the race. A point that specially interests Now Zealand, where there has been some outcry against an inordinate killing of whales, is that, in proportion to' the value of the products obtained, far more damage is done to the race in temperature and sub-tropical waters, such as South Africa stations, than hv •.whaling) stations and factory-ships in the dependencies of the Falkland Islands. The economic extravagance of whalng in South African waters is strongly emphasised.