NEW ZEALAND FISHES

Evening Star, Issue 21569, 15 November 1933, Page 13

NEW ZEALAND FISHES

LECTURE BY MR D. H. GRAHAM An instructive and extremely interesting lecture entitled ‘ New Zealand Fishes Showing Parental Care ’ was given by-Mr D. H. Graham at the annual meeting of the Otago Institute last nightjthe address being illustrated by a number of lantern slides. Mr Graham opened by stating that most people looked on fish as lacking in affection, barely recognising any duty to any member of the family, a creature whose chief aim was that of feeding. it had long been known that the English stickleback showed care of its future offspring. Further instances were afforded in Queensland, one in Africa, and one in North America of fish that were known to protect their young at the expense of their lives. He had - been '-particularly■•.•.•fortunate in being able to record two of their local fishes showing complete care and one with partial protection—Ml three were shore-loving fishes. The first two were the cockabully and the taumaka, and the one with partial care was the sucker fish. The last-named was found everywhere up and down the coastline pnder rocks and in rock pools', and the largest, female be had seen measured was five inches, though. the average would be about three inches. The male did not attain more than 2Jin in length.. Spawning took place in very shallow water, .chiefly close ltd. low..tide mark. The females .fixed ..'their eggs to the undersurface of rocks, stones, . and empty shells, but only as a rule on •smooth' or ''comparatively ...smooth ..surfaces; The eggs were laid in irregular masses, and medium-sized sucker fish, Biin in length, produced up to 1,600 eggs. He had. often turned over rocks with females depositing their eggs to the undersurface, and they soon wriggled out of sight. .The male had a tendency to parental care, and, .small as he was, would guard the egg mass at the risk of his life. Once the female deposited hef eggs the male spent the whole of his time after he had-fertilised them in moving about over the mass of eggs, apparently keeping the spaces between the eggs free of sediment. It was found that the male did not attempt to feed during his fatherly duties of parental -care. It-was noticed, however, that once the eggs hatched the male was caught and devoured by the female. The next fish showing parental care w;s a shore-loving fish known ap taumaka, this fish being found everywhere both inside the harbour and up and down the coast. The average -length was about spven .inches, its favourite habitat being under rocks where there was a little sand, mud, and small stones. On turning over a rock recently he found a taiimaka in a muddy canty containing a small quantity of water, and owing to the formation of the. rock the fish must have been a prisoner. It did not dart away as usual, but kept perfectly still except for a slight movement of its tail,. quietly lashing the water left in the depression. He found quite close to it a. ball which provedto be the eggs of the taumaka. Nothing would induce the fish to, move'.away, and the total number of eggs m the ball was 34,440. It was found on examination that the placid fish in every instance was a .male. It seemed that the fish either the male or the .female, made a’hole largo enough to enable it to enter, scoured' a hole in which, the female-laid; her egg mass, then came out, the male entered, closed up the entrance from within,- and fertilised the eggv remaining with them until they were hatched and able to swim away. With all this parental care the taumaka was not common.-. • Dealing with cockabullies, the speaker said they were found throughout New Zealand along -the coastline, m all depths down to 100 fathoms. Small as the cockabully was, it would guard its eggs at the expense of its litc; refusing a" food while the eggs were being hatched. , , , , The speaker was accorded a hearty vote of thanks for his address.