MARINE LIFE

Otago Witness, Issue 3519, 23 August 1921, Page 5

MARINE LIFE

LECTURE BY HON. G. M. THOMSON. An illustrated lecture on “Our Fishes and Other s>eu Lite’’ was given by the lion. G. .Vi. Thomson m Uie Medical bcuool icctiue room, Ring street, lust week. Mr G. llowos, president ol the New Zealand Institute, presided over a good attendance, The lecture was given in aid ol the bunds of the Naturalists' Field Club, of which Air Thomson is president. 1 he Chairman said that in October, 1872, the first mettiiur of the Field Club nad been held, and this was really their jubilee year, ihe club had always been hard up, and, though much valuable research work had been done by members, very little had been put on record, and much had been permanently lost through lack of funds lor publication. ihe Hon. G. M. Thomson commented on the luet that many important events in the history of Dunedin occurred in 1871. no doubt partly owing to the fact that in that year the University were started, it had recently been pointed out that foothail was first played in Dunedin in 1871, and that was the year in which the Dunedin Choral Society was founded. It was at that time that the Feld Club was stalled by a gentleman known as "Pakcha” Thompson, a member of the Otago Daily T hues staiffc, who did a great deal of valuable work, especially in the held on which he was to speak to them that evening. Air Thomson went on to sneak of the characteristics that made Dunedin a peculiarly attractive locality for tile activities of a held club. lie began his lecture proper by pointing out that our knowledge of marine life was very limited, and what wo did not know was simply colossal. He ran over the various great, divisions of marine life from mollusca to diatoms, pointing out the extraordinary quantity of life existing in the sea and tiie great fields in which practically no investigation has yet been done. Every female groper had from four to five million eggs* in a season. If they all hatched and came to maturity the sea would be actually stiff with them, and the groper was only one of multitudes of specks. A crab, again, was known t.o produce about 3,000,000 larva), and they also would speedily take possession of the sea were it not for the destruction carried on among their young on a vast scale. Of very tiny living organisms over 460,000 had been found in a litre of apparently clear water. All knowledge of this kind had a very practical bearing on the fisheries of the world, for the abundance of big fish depended on their food supply, which was found in the smaller forms of marine life. With the aid of a large scale map' he showed how absurd was the suggestion that trawlers working from Port Chalmers could seriously affect# the supply of fish in the neighbourhood, confined as the trawlers were to the shallow area in which they could reach the bottom. A to 45 different kinds of fish were to be seen in local fish shops at different times, and of these about 25 varieties were common. The lecturer went on to discuss the age of fish, and said that- this could be calculated with considerable accuracy from the scales of the fish. The migration of fish he believed was entirely a matter of food supply. Ho described the gigantic swarms of fish that sometimes appeared in our waters, and said that their origin and their fate vyas largely a mystery. Speaking of individual fish, he said that the dogfish was quite good for food in spite of the prejudice against it. The current idea among fishermen that it was very destructive of other fish was quite erroneous. Elephant fish was another kind that might be generally used. The red cod was the most extraordinarily voracious fish he knew. “Whale feed” was a misnomer. For a great part of the year it was the most valuable and abundant fish food we had. It was a swimming stage of a big, clumsy shrimp that lived on the bottom of the eea. The lecturer then had thrown on the screen a number of interesting views of the fish hatcheries at, Porto-bollo, and later of such fish as the New Zealand bream, the moki, the teraki, barracouta, lemon sole, common sar.d flounder, common sole, brill, turbot, sea perch, pigfish, blue cod. crabs, crayfish, lobsters, shore hoppers, and others. Many interesting facts were given about these fish, as, for instance, the turbot, with its wonderful power of swiftly changing colour in harmony with its surroundings*. Ho stated that of ISS turbot brought out to Portobello eight years ago, only eight had been lost, owing to the extreme care and cleanliness with which they had been handled. They wore now about 2ft long, but they would not spawn. It appeared that they had to get into deep water in order to spawn, and so they had all been turned cut except 14 that were kept for visitors to look at. In concluding, he expressed the opinion that the development of our fisheries ought to be much more seriously supported by the Government than it was. On the motion of the .'.h airman a very hearty vote of thanks was accorded the lecturer.