IN TOUCH WITH NATURE

Otago Daily Times, Issue 21837, 27 December 1932, Page 2

IN TOUCH WITH NATURE

ELECTRIC FISHES. POSSESSION OF POWER A MYSTERY. By J. Drummond, F.L.S., F.Z.S. Although electric cels are not included in a bibliography of New Zealand fishes compiled by Mr W. J. Phillips in the Dominion Museum, Wellington, Mr J. Claridge, Glen Eden, near Auckland City, states that about 60 years ago when the Government steamer Luna, commanded by genial Captain Fairchild, was at Wanganui, he was taken on board to see two electric cels in a tank on the deck, and received a shock from one of them. If these were members of the group of fishes known to science as Electrophorus, bearers of electricity, it is regrettable that experiences with them were not recorded. Captain Fairchild was a remarkable man, a good sailor, a capable mariner, a delightful companion, and an enthusiastic naturalist. To sympathetic ears, he spoke for hours about the seabirds and tiie fishes he knew, but, like other men who lead active lives, he found writing laborious and only fragments of his wide knowledge have been preserved. Another note is from Mr D. F. Watson, a fisherman, of Paraparamu, west coast of Wellington province. About 12 years ago, he writes, his brother and ho were hauling a long line between Tokomapuna Island and Rangatira Point on Kapiti Island. His brother said suddenly: “I’m getting electric shocks. I’ve hooked an electric skate; the quicker that fish gets off the better.” They did not get the fish on board, but they are confident that an elecric fish had been in contact with a part of the line. It probably let go when near the surface. Later, they caught an electric-skate, or electric-ray, in a wharehau net set in Waiorua Bay, near Webber’s homestead, Kapiti Island, about three miles from the place where the first shock was felt.

Somewhat strangely, electric cels, equipped with living batteries, and ranking amongst Nature’s amazing whims, have attracted less attention than many very ordinary fishes, which happen to be suitable for human food. The excuse is that utility comes first, as in the destruction of beautiful New Zealand forests to make way for green pastures. Food-fishes are important, because they were the basis of one of the earliest human industries and because they now represent an industry of great magnitude. It is estimated that the catches of marine and fresh-water fishes in the ■world have a total value of about £100,000,000 a year. This may be a close guess at the value of fisheries in civilised countries, but it cannot take into account the operations of primitive peoples, many of whom live almost by fish alone. Japan’s fisheries are the most valuable. They employ about 2,000,000 men and their value is estimated at £30,500,000 a year. The fish output from the United Kingdom is valued at £20,250,000 a year, from the United States at £19,000,000. Every book on fishes has pages on trout, salmon and sharks. Trout have an extensive literature of their own. The neglected electric eel has only scrappy references in fish literature. Its wonderful electric organs are modified muscles at the end of the tail. An electric eel is more tail than .anything else. One in the aquarium at the New York Zoological Gardens is five feet six inches long. Its head is five inches long, its body six inches. All the rest is tail, which is thick and heavy, and a large part of it bears the organ that makes this fish famous. The organ is compoled of countless minute cells, served by nerves that run from the spinal cord. Electric eels in the New York Aquarium almost six feet long, swim quietly toward fishes thrown to them for food, and stun them with an electric discharge before seizing them. Attendants who move the electric eels with nets wear rubber gloves. As in case of the electric ray, the electric eel’s battery probably, is soon exhausted; but, after a rest it is replenished. The electric ray’s battery is weaker than the electric eel’s, but its shock has been felt through a stream of water poured on a ray when dragged ashore.

The need for this equipment in fishes is not understood, perhaps never will be understood. Lung-fishes which have well developed lungs fitted for breathing air, and which, as Dr Starr Jordan states, arose from the vast darkness of Palffiozoic times, their origin having been traced to primitive sharks, are less puzzling. In searching for causes and explanations of developments in the animal kingdom, it may be thought that in past ages some fishes found that lack of water rendered their gills useless. They developed lungs as well as gills, and survived by breathing air when necessary. Their descendants are the lunglishes of our own times. At least one of them, the barramunda of Queensland, can breathe by either lungs or gill separately, or by both simultaneously. While it lives mainly in water, it occasionally, by using its lungs, goes on the land. The presence of lungs in fishes may be explained on the theory set forth. There is no theory to explain why a few widely separated groups of fishes should have called to their aid a subtle and powerful force that man has not evoked until millions of years afterwards. Many of Nature’s ways are mysterious. None is more so than the use of electricity by fishes. Kiwis are plentiful at Deep-water Cove, Bay of Islands, reports Mr M. Cross, who has supplied the following notes on these quaint nocturnal birds; —“We meet them on the paths at night, when we go about with torch or lantern. They stroll in pairs into our outdoor dining room. It has only roof and floor, with large puriri and kohikohi trees growing from the ground through the roof, with a leafy bower of native trees for sides. Kiwis, attracted by the light, think that they are still in their native bush. My son found a kiwi’s nest, with a male and female bird, and one egg. He left then, undisturbed. This is not an uncommon find here. Last year the late Dr Rayncr, visiting Deep-water Cove with Mr Peter Gardner, of Kamo, caught two kiwis that had come into our outdoor dining room. They were quite tame and unafraid. They were carried to Mr White-Wickham’s fishing bungalow and placed on the rockery there, and they had their photographs taken. Afterwards they strolled off together through the native bush without undue hurry. Five years ago, Lord and Lady Helper, with Lord Summelcyton. visiting hero caught a kiwi. They were going to petition (he Government lo allow them to take the bird to England., Lady Helper grew compassionate towards the kiwi because it whistled continuously for its mate in the stillness of the night. Next morning she released it from captivity.”

There seems to be no doubt that the New Zealand quail, once very plentiful, is extinct. Its discovery is reported occasionally, but the reports are based on the presence of an introduced Australian quail, which the native species resembled. A Gisborne resident last saw a pair of native quail on Lakes Station, North Canterbury, about 65 years ago. Even then, he writes, the species was very rare. It lived on a block of stony land, on which grew stunted manuka and wild Irishman. As there were thousands of grasshoppers, the quail had ample food.

About 40 years ago this correspondent, while in Christchurch, received a message to go to Hopefield Station, Hanmer Plains, and to bring with him a lot of cartridges, as some of the lagoons swarmed with paradise ducks. He went post-haste, and his friend and he camped close to the lagoons. He has seen remarkable flocks of ducks, but none as huge as that flock at Hopefield. His friend estimated the number at 5000. The result was disappointing. After they had shot a bag they began to collect the ducks, which proved to be smaller in the bodies than domestic pigeons. They had been starving and were hardly better than bundles of feathers. The lagoons had no weeds W other vegetation. The ducks disappeared by degrees, but many were too weak to fly away and probably died there. Mr F. Milner, principal of the Waitaki High School, has received many letters from Southland and Otago reporting the increase of German owls, first imported from the Old Country about 25 years ago. In the same districts, it is stated, small native birds have decreased. At his own expenses, Mr Milner has paid for the destruction of more than 100 owls. He has cleared them from the school shrubberies. Mr C. E. Stratford states that at Waitaki the presence of the owls has a sinister effect on small birds, causing them to cease singing and creating in their breasts fear in place of joy. He has discovered that the owls nest amongst rocks and in disused rabbit burrow's rather than in hollow trees, a habit recorded in this column by Mr F. S. Whitcombe, Owaka, Otago. Mr Stratford’s observations show that the owls particularly attack goldfinches, but the skeletons of waxeyes, grey warblers, and fantails evidence their destruction of defenceless native birds. Sparrows seem to be too quick for them.