LIFE IN THE SEAS

Evening Star, Issue 20374, 4 January 1930, Page 13

LIFE IN THE SEAS

, _ f HISTORY OF COASTAL FISH RESEARCH work at portobello ADVANCEMENT OF ECONOMIC INDUSTRY From both economic and scientific points of view an intensive work in the study of the life history _ of the fish on the Otago coast still lies before the marine fisheries investigation station.at Portobello. . . . Since it was opened twenty-sis years ago to-day the Portobello station has made many valuable contributions to the science of marine life and the economic advancement of the fishing industry. A wider vista of virgin field opens out now, and with the arrival of Mr David Hi Graham at Portobello as biologist unrelenting pioneer work-of research will be initiated. , The station, in Mr Graham’s opinion, has every chance of becoming more widely known, and he sees in the work before him an almost unlimited opportunity of the station providing and knowledge for students, universities, and schools, not only in New Zealand, but overseas, and, through the close study of the life history of the habitats of the coastal waters, a tremendous contribution to the fishing industry, an economic national industry. Born in Lyttelton, Mr Graham was for some years the owner of, a backblocks farm. He injured his back,and for three years he was in hospital. During that period he made an acute study of natural history, a hobby in his farming days, and, assisted by Mr Gilbert Archey’s advice, he worked, under a Government grant, on the' mosquito problems of Auckland. Before that he’made a research of crustacean and marine life. Mr Graham _is a born naturalist and scientist. He is delighted with the possibilities offered by the well-equipped Portobello station, and the board is sanguine that, as the biologist' possesses indefatigable energy and enthusiasm, his work will bring about marked results. . Npstling on a promontory opposite Quarantine Island, the station is .ideally situated. Its ■ equipment is complete, and the launch Karoro is a most serviceable craft for all work. The station has long' been a place of interest to visitors, and the aquarium there_has assisted in making the activity at Portobello more widely known,, _ Largely instrumental in the creation of the station, the Hon! G. M. Thomson, M.L.G., is still actively, engaged in prosecuting the advancement of the research work. Yesterday a ‘ Star ’ man accompanied him to Portobello. . , The station was originally established to provide a place in which fish could be kept in confinement. 1 A hatchery station board, with Mr Thomson as chairman, was formed after the. Government had promised to - subsidise the grants of £250 each, from. the Acclimatisation Society and the New Zealand Institute. When the application for assistance was first made to the Government Mr Thomson estimated that the ponds, tanks, and buildings would cost £l,lOO, but the Rt. Hon. R. J Seddon obtained a-report from the Public Works Department. While the local enthusiasts had, nerhaps, underestimated the cost, , the department grossly over-estimated the necessary expenditure. £3,000 was set down as the department’s figure. By way of compromise, Mr Thomson raised , his estimates to £1,400, and, to the surprise of- the promoters of the scheme. Mr Seddon promptly made, the.- full allocation. The station came into being through the ardent efforts of a few naturalists and scientists. Their object achieved, they db’ not rest, and throughout the, whole twenty-six years of its existence the board has not cost one penny for overhead secretarihl expenses. Encouraged by the’ possibilities of science, Mr Thomson had no qualms in seeking assistance, and the staunch jetty which to this day runs out into the channel cost the board only ,£3 The sleepers were given by the Railway Department, and - the Harbour Board drova the piles which .it suppliedThe expenditure of £3 was, entailed by the engagement of a carpenter, to erect the hand railings. . A walk was throwu across the bay, and: concrete ponds were constructed. The necessary buildings were erected, and, an 18,000 gal tank,. into which salt water is still pumped by motor at high tide, was built into the rocky wall. , The earliest attempts in the direction of rearing fish from overseas in captivity were made with, herring ova. The ova have not yet been received, as they have not been carried overseas alive. But European lobsters, crabs, and turbot (the finest of all European flat fish) have been successfully brought out to Portobello and liberated in New Zea-, land seas. Lobsters have been kept continuously, more or less, at the station since 1907. A few adults have been liberated, and larvae to the number of probably 2,000,000 have been set adrift year after year. The present stock of lobsters, a total of thirty-six, which are in one of the big ponds, was brought out in 1923. The females are all egg-bearing, carrying on an average over 10,000 eggs apiece. All the lobsters imported to Portobello have been about ten years old, and they have lived for another thirteen years. None of the liberated lobsters or progeny has yet been recovered. Larval lobsters swim for only three weeks, and then seek the bottom. However, the Station Board has the strongly expressed opinion that the experiment of lobster mj.tralisation is likely to prove successful The ’majority of the larva, said Mr Thomson, probably come to rest at the

sea bottom at a comparatively shelf distance from the point, of liberation, partly in Blueskin Bay and partly a* sheltered; localities (such as tahag Point, Moeraki, etc.), within three weeks of liberation. Mr Thomson said it bad to be borne in mind that from the time the lobster larvae sink to th«* bottom until they are sexually mature a period of probably at least eight or nine years, they are scarcely ever seen. Both adult European crabs and _ larvae, estimated at 13 ,000,000, have been liberated from the station, but no results have ever been obtained from tans. The turbot have been only a side hue. The matured turbot is estimated' to produce about 5,000,000 eggs, but vn the shallow water off the Portobello ponds flat fish cannot. emit their ova 5 and after keeping turbot in the ponds till some of them were as much as 23m in length the large fish, about 180 m number, were all turned out in Tautnku Bay, south of Long Point, where the Manuka was wrecked, about five or sis years ago. They have ,not been met with since. For eight years prior to his transfer to Wellington Mr Maxwell W. was the biologist at the laboratory * In Wellington he is working as assistant to Mr Hefford, Chief Inspector of Fisheries. Thus for nearly eighteen months the biological: work at Portobello has been very much at a standstill. Now that Mr Graham has taken over the work with enthusiasm, it Is anticipated that ■ excellent results will follow. The hydrographic work of tha station, the taking of marine temperatures and water samples for salinity,-tow-netting ‘ for pelagic organisms,and dredging have .been carried on; regularly, ny the staff, Messrs W,Adams and S. Broadley. Latterly they, have been very ably assisted by, Mr Ralph Shropshire, the hydrographenof the Byrd expedition. All salinity, samples are tested at the Dunedin branch in‘Hanover street of the Dominion Laboratory, but it is expected that Mr Graham will ultimately be able to \test; al Isamples for salinity, phosphates, nitrates, and hydrogenion estimation. Mr Scofield, 1 formerly lighfckeeper at Cape Saunders, took temperatures and collected • sample# regularly at the Cape for thef station.He has since been transferred to Puysegur Point, where he is continuing his good work. ; - The hydrographic results are of importance in consideration of the distribution of diatons, perediriaa, and other miqute on which fish feed, and the distribution of the fish appears to depend on those and other marine organisms which go up - the coast in vast numbers at various periods of the year. Slight changes in temperatures and salintiy often determine the occurrence of, these marine organisms. Mr Thomson instanced the clearing out of the fish from Otago Harbour in the winter. During the summer moki and kelpfish. were caught on the channel off the station, but they were all gone at the beginning of May. “The water in the harbour dropped, perhaps, to 40deg, but tha current flowing up the east coast never fell below 47deg in temperature. Tha moki and kelpfish returned to Otago Harbour in November. Only _ small flounders were to be found within the harbour confines in winter time. A cold clear night after the snowstorm caused the death of forty blue cod in the ponds at Portobello some time back. , ■ ” ■ , ■ ,

• The drift of tho currents on the coast is. also of. great economic/ importance. Two sets of drift bottle experiments have been made from the station. ‘ iwo facts have been established. , All bottles set* free more .than three of four miles from/Otago Heads have gone up th® coast to the north. - From Banks i?eninSji|a proportion of them have swept out to • the Chatham islands, while others have'* been rtrieved as far north as Cape Turnagaui and as far west as Farewell Spit.; None travelled south. Bottles liberated' within three miles of the Heads have driften into Blueskia Bay and then to the north: hence it as thought" that- the lobsters have found their ‘way; into the bays to the north of the Heads. . , On on© occasion among - many taio station showed its .value. Fishermen, throughout New Zealand clamoured for, protection from dogfish, and the Go-' vernment oered Is a head royalty Th® dogfish is the smallest of the New Zealand sharks, varying from 18in to in length; it is also the most abundant* Dogfish are common in Otago Harbour; uni on the coast. Fishermen savagely, destroyed all dogfish under the impression that they were destructive to fish* The statin proved that that was a W mistake. Front observations made at the station!dogfish appeared,to seek their food near the bottom of tn® water, groping along the banks and feeding chiefly on Crustacea and worms. The stomachs of hundreds of dogfish were opened, and not a single one contained fish. In 'the stomachs of tfa® specific examples Crustacea. of many kinds—-crabs, crayfish, shrimps, whale feed, and isopods—were the most common food. Nest in order of palate preference were worms' and' occasionally octopus.- Thb idea of oering a bonus tor the destruction of dogfish was proved to be based oh a fallacy, aiid the oner was withdrawn. Dogfish, however, are admittedly troublesome to nshermea through removing their bait. In the library at the station tu® shelves hold a ' unique collection if papers and books.. Over 2,000 are catalogued, and inquiries for information from the references. are frequently received from all parts of the dominion.