BIOLOGY OF WHALES

Otago Daily Times, Issue 21948, 9 May 1933, Page 9

BIOLOGY OF WHALES

THEIR FOOD AND HABITS. " In dealing with living things as such, it is inevitable that one should study them in relation to their environment," said Professor C. E. Percival in introducing his subject, "The Biology of Whales," as the presidential address to the Canterbury College Scientific Society. In studying a particular species ono must know what defined its living conditions, the professor continued. The study of whales, which had made great advances of recent years, was a branch of oceanography, the charting of oceans in every direction. Since 1830 the zoologist and the botanist, arid more recently the chemist and the physicist, had been drawn into these investigations. " Just as it has been said that all flesh is grass, so one may say that all fish is diatoms—small plant animals which form the chief food of sea water," continued the speaker. "At different seasons of the year and in different portions of the globe, oceans differ in solidity and in the amount of food present. It happens sometimes that the top layers of sea become vitiated of living diatoms or sea food through the light energy from the sun causing increased growth followed by a ' famine.' Again these diatoms are present in some portions of the northern hemisphere in such quantities that a ship may pass through water coloured by their presence for a whole day." From 1924, when the British Government began investigations iu the biology of southern whales, great advances had been made in whale fisheries. The North Atlantic region, so popular for 300 years with whalers seeking the whale bone and oil of the sperm whale, gave way to the South Atlantic fisheries, with their centre at 'South Georgia. Here the fin whale, which was found to a length of 70 feet, and the blue whale, which was found to a length of 100 feet, were discovered in great numbers. It had been revealed that the blue whales mated in June and the calf was born seven yards long in the following May. It increased its length to 16 yards by the time of weaning and was 23 yards long when it began breeding in its third year of existence.