NATURE NOTES

New Zealand Herald, Volume LXXII, Issue 22142, 22 June 1935, Page 1 (Supplement)

NATURE NOTES

BT J. DBITIEMION'D, F.L.S., F.Z.S.

QUEER FISH

With a -wish to help, not to criticise, Mr. D. H. McKetizie, Stanley Avenue, Miiford, has written in a friendly strain adverse to an opinion set forth in this column a few weeks ago that the climbing perch does not climb. From his experiences in Suva, Fiji, thirty-seven years ago, he asserts that it does climb. His mate and be accepted an invitation to visit the home of Mr. J. Waters, curio-dealer and photographer, at Walu Bay, a suburb of Suva. They walked through a growth of mangroves. On the trunks and limbs they saw many small fish, which sprang off, dropped into the water, and scuttled away as the strangers came along.

He has preserved his notes of that walk through the mangroves. " There are fish," the enti-y records, "that come out of the prater and climb trees." Accompanying the notes is a rough drawing of a fish two inches and a-half long. Stung by ridicule with which his story was received, Mr. McKenzie, a few days later, crossed the street from the Club Hotel, where he stayed, and went over a retaining wall on to the beach The tide was low and water lay in shallow patches on the rotting coral and soapstone. A small fish suddenly scuttled over a pool and made several skips to another pool. Mr. McKenzie gave chase, but it; took him almost half an hour to catch the fish, which he showed triumphantly to scoffers who had poked fun at 'him. From the balcony of the hotel it dropped to the ground, skipped across the road and regained the water.

His reference is to the mudskipper, not to the climbing perch. The climbing perch. Anabas scandens, is found in India, Ceylon and the Malay Archipelago. The mudskipper, Periopthaltnus koelreuteri, is most frequently reported from tropical Africa, Asia" and Polynesia. They belong to different fish families or grouts. Both are equipped with accessory breathing organs. By breathing air they can live out of water for a limited time and can migrate from one area o'f water to another.

Mr. J. R. Norman, assistant keeper in the department of zoology at the British Museum, in " A History of Fishes," rives an account of the mudskipper's habits similar to Mr. McKenzie's notes. " The remarkable little fish," Mr. Norman writes, "spends much time walking; or skipping on the mudflats of mangrove swamps at low tide in search o:r food. It is fond of climbing on to mangrove roots and of basking in the sun perched on a stone in a pool. "VHiile out of water the large gill-chambers are kept filled with air. It is so accustomed to live out of water that it is believed to be unable to live in water far a long time." Another eminent naturalist states that a mudskipper on land is as agile as a lizard.

Mr. Norman may be accepted as a careful writer and compiler. He is the authority for the statement that the climbing perch d>Des not climb. It is a queer fish, one o:f the queerest, but its ability to climb palm trees and suck their juices is regarded by him as a legend, started 138 years ago by a lieutenant in the Danish East India Company, who took one in a slit in a palm tree that grew near a pond. The fact is not doubted. The conclusion is denied by am Indian naturalist, Dr. Das. His explanation is that climbing perches have a habit of migrating from pond to pond at night. They come out of the water after a shower of ram to search gardens for earthworms. Some are seized by crows or kites and are placed in the forks of trees. They give a wrong impression that they climbed the trees.

If Mr Norman and Dr. Das have the rights of it, the old legend dies hard. In 1925, Dr. David Starr Jordan, the highest authority on fish in his day, quoted with approval a report by Captain J. Mitchell that, when heavy rain falls and runs dr>wn the trunks of palm trees, climbing perches crawl up the trunks to a height of five or seven feet. Climbing perches, in water, like to ascend streams against the current. Captain Mitchell's theory is that the same instinct leads them to ascend trees against the down-flow. A book on fish published only two years ago endorses the legend with the following thoroughness: " ('limbing perches leave the water in times of drought. If their quest for a pond or a stream that has not dried up proves unsuccessful, they climb a tre<- in order to discover a place were water has accumulated in the cup formed by the junction of branches." The tree-climbing legend is more easily rejected than accepted.

Climbing perches wriggle on land bv using their breast-fins and their gillcovers. The gill-covers can be moved to an unusual degree. They can be raised or turned outwards at almost a right angle to the body. Alternately spread out and fixed firmly to the ground by sharp spines, they enable the fish to get along. The breast-fins and the tail push the body. When the spines are fixed in the ground the gill-covers are merely closed, and the fish advances about half an inch.

Tje mudskipper, to further its unnatural accomplishment, has developed modifications in its breast-fins. These are attached to the end of a process like a muscular arm, which is moved backwards and forwards. The breastfins are thrown forward and then are lowered on to the ground. Thev drag the body. As each step covers half an inch, and as many steps are taken rapidly, good process is made. While the breast-fins are forward, ready for a fresh the body is supported by other fins. Short jumps may be made by usmg the breast-fins alone. Long jumps are made by a stroke of the tail. It is curled forward and sideways, and is suddenly straightened.

These two groups of fish stand ont in strangeness from the multitudinous creatures that live normally in water. other species, although less interesting, have strange habits. In one of the admirable* zoological publications of the University of California Press. Mr. C. L Hubbs records observations by Mr J. B. Joplin, of Santa Ann, California, on the habits of fish that strictly keep to a time-table. During three months on the second, third and fourth nights after the full moon, great shoals of the species come through the breakers at full tide to deposit eggs on the sand. After the tide recedes they wriggle tail downwards into the sand. Where the surface of the sand had been broken, as many as eight or ten, males and females, were found together Sometimes only one female is "seen, nothing but its head showing. They come in at night only, usually between 10 p.m. and 1 a.m. The run, as a rule, continues for thnse hours, or longer. Mr. Joplin observed them for thirty years. They come so regularly that he seldom missed them.