TWO GREAT WORKS

Evening Star, Issue 19549, 6 May 1927, Page 8

TWO GREAT WORKS

- . SALMON AND OYSTERS LIFETIME OF SERVICE The retirement of Mr L. F. Ayson, Chief Inspector of Fisheries, on Saturday last, brings to a close a career rich in pisclcultural experience, and of the greatest value to New Zealand fisheries (says the Wellington ‘ Post ’). Not only was Mr Ayson actively connected with the first trout brought to Nev Zealand by the Otago Acclimatisation Society, but he has successfully acclimatised the quinuat and Atlantic salmon, a ieat that has roused the admiration of eminent piscatorial authorities the world over, an accomplishment that is bound to be of increasing importance to the dominion in establishing a secondary industry looked upon in America as one of the most important. He has also saved the North Island rock oyster beds from extermination, and has made their artificial cultivation a success. BEGAN AS A BOY. The story of how Mr Ayson was first attracted to fish culture is interesting. His father, a keen Scottish angler, came to the dominion in 1853, and settled in Otago. One of his keenest regrets was that the beautiful streams in New Zealand had no trout, and for a long time he found it difficult to believe. Others regretted the fact as well, and the late Mr W, Pillans and other members of the Otago Acclimatisation Society went to some expense to bring a small number of eggs from the Tasmanian Government hatchery on the Plenty River. Mr Pillans and Mr Ayson’s father were neighbors on a small stream near Balelutha, and when Mr Pillans made a box and batched out the trout eggs, eventually being able to show a tew small trout, Mr L. F. Ayson, then a lad, was as keenly interested in 4hc experiment as anyone, So keen was he and so thoroughly did he enter into the work that when Mr Pillans found it necessary to go away for a considerable time be left the young fish in his care. Dipping into piscatorial works, the youngster made as extensive a study of the matter as he could, and when the trout became sufficiently numerous and stripping was commenced ho proved most useful. FIRST OFFICIAL APPOINTMENT. This interest in all pertaining to fish culture became his chief hobby, and when in 1885 a supervisor for the then new Masterton hatchery was advertised for Mr Ayson, who had continued to study ■ the subject, was selected. Those were strenuous days at the hatchery, because the ponds had to bo dug, bush cleared, and a great deal of hard work was necessary. There was no trapping in those days, the method being to go out after dark with a lamp strapped to the middle, and for the fish on the spawning beds with a landing net. and many were the days in the e°;gcollecting period when Mr Ayson and nis assistant, after .eight hours with pick and shovel, spent a good portion of the night in the water, which is certainly chilly-in the spawning season. Masterton was designed to supply most ot the North Island with ova, and was heavily stocked with brood fish. These were the days when the rivers were too sparsely stocked to permit ot successful trapping for stripping, and as experiments were being made in the acclimatisation of different species quite a number of varieties of trout were kept in the Mastertou nouds. There were American brook

trout ■ (Salvelinus fontinalis), American rainbow (Sahno irideus), Scotch brown trout (Salma fario), and Loch Levon trout (Sahno levenensisl. EARLY SALMON ATTEMPTS. For fifteen years Mr Ayson continued in charge of the Masterton hatchery during which time eggs were sent all over the North Island, and as far as New South Wales. So extensive woro the sales of egg&o in fact, that they completely paid the'working expenses of the hatchery. In 1898 he was appointed Chief Inspector of Fisheries, and at once turned bis attention to the study of the acclimatisation of salmon. The first attempt to bring out salmon eggs wac made by the Government in 1868, but the shipment was not satisfactory. Fifteen further shipments were obtained between 1868 and ISO2, but the losses, because of lack of skilful attention on the voyage, were heavy, in no case less than 25 per cent., and in some cases 50 per cent. These were the Atlantic salmon i.Salmo salar) A few smolts appeared as the result of liberations by _ the societies in the Aparima, but no spawning Atlantic salmon appeared in any of the rivers until half a dozen years after liberations of Government eggs in the Waiau tributaries by Mr Ayson. All the appearances of salmon in the Waiau coincide with the liberation of Government eggs in 1908, 1909, and 1911. . , . , Mr Ayson has always maintained that concentration on one river, from which, when acclimatisation is assured, the fish will spread naturally to other rivers, was the only sensible means of tackling the acclimatisation of salmon, and certainly the early practice of parcelling out the eggs to various societies did not produce the results which, by concentrating on the Waitaki, he has accomplished with the quinnat salmon, There is also no doubt that Atlantic salmon eggs, in the early days of acclimatisation, were put in unsuitable streams.. Quinnat (Onchorbynchus-tschawytscha) eggs were first introduced in . 1875, but up to 1880 the societies were not successful. In 1899 the Government, on the advice of Mr A-vson, resolved tc male© a determined and systematic effort. The site chosen for_ the hatchery was on the Hakataramea River, one of the tributaries of the Upper Waitaki. closely allied in its natural characteristics with the salmon streams of the nveie> of the Pacific Coast of North America. In January, 1900, the first shipment of eggs reached. New Zealand from the Baird Hatchery in California, coming out in charge of Mr Larabson, its superintendent. FIRST SUCCESSFUL SHIPMENT.

Before these eggs were brought out Mr Lambson and Mr Ayson entered into correspondence on the best methods of choice, packing, and treatment during the voyage. The age at which the eggs should be taken was an. important matter. The temperature at which the eggs should bo kept during the voyage necessitated their being attended to in the vessel’s cold stores. They

must not reach a temperature above 54deg Fahrenheit. Frequent picking over to remove the dead eggs was necessary. To ensure equal temperature th<x water used to ropolmsh the eggs was put in the cold chambers overnight and run through the eggs in the morning, helping to increase the oxygen supply, and keep the embryos strong throughout the trip. Mr Lambson arrived with a loss of only 5 per cent., but he was uot satisfied with that, and on the next trip, after further collaboration with Mr Ayson, 99£ per cent, of the eggs were good on arrival. Following these two importations Mr Ayson made four trips to America for eggs, using the same methods, and did not exceed 1 per cent. loss with eggs from either Canada or Britain. A UNIQUE EXPERIENCE.

To-day the acclimatisation of salmon, both Atlantic and quinuat, is assured, and, quite apart from all he has done for the acclimatisation of trout in New Zealand, Mr Ayson, qualified by a unique piscatorial experience, has laid the foundations of a great industry. Ho has superintended the installation of hatcheries at nearly every acclimatisation society iue New Zealand, and given given them helpful advice on every matter connected with trout culture and the stocking of streams. It has necessitated a vast amount of travelling, and he has been probably the most übiquitous servant of the Government. Winter is the spawning season. and the work at the salmon hatchery is particularly cold and fatiguing, but Mr Ayson has always done more than his share of the manual work he might well have left to others, chiefly because his interest in all pertaining to fish culture increased rather than diminished with the years. _ In the course of his investigations he has visited hatcheries in Italy, Switzerland, France, Germany (twice), Scotland, Ireland, Canada (several times), and the United States (several times), and has accumulated a knowledge of fresh water fisheries, that has proved of inestimable value to New Zealand. ARTIFICIAL OYSTER CULTURE. In marine fisheries ha has also taken the keenest and most valuable interest. One of the biggest achievements that lie to Mr Ayson’s credit is the successful campaign he has waged for the preservation of the North Island rock oyster. Indiscriminate picking had so depleted the oysters that_ only onethird of the original supply remained, when in 1899 the Government decided to take steps to conserve the beds. The building of rock walls in vho Bay of Islands was planned by Mr Ayson, and the artificial cultivation of oysters by this means has most successful. The strictness of the ranging of these beds is well known, and, though it is a difficult problem over a scattered'field, no revenue coastguard service elsewhere is more' efficient, as those who steal Government oysters have disoovejsai.