Chapter VI

FISHES

The classification adopted for the fishes which have been introduced into New Zealand is that of Professor G. A. Boulenger in the Cambridge Natural History.

Class PISCES

Order TELEOSTEI

Family CLUPEIDÆ

Herring (Clupea harengus)

To the popular mind the introduction of the herring into New

Zealand waters is the most desirable form of acclimatisation work which could be undertaken, as it is considered that its commercial value to this country would be so great. The success which has attended the introduction of certain species of Salmonidæ has led unthinking persons into the belief that it should be quite easy to introduce other species of desirable fish, and as the majority of people are unthinking, even if they do not come under Carlyle's famous dictum, it is not to be wondered at that the introduction of the herring has been frequently urged. A fairly full report of the efforts which have been made, and of the difficulties which have to be overcome has recently been, or is about to be, published in a Bulletin of the New Zealand Science and Art Board on "The History of the Portobello Marine Fish Hatchery and Biological Station."

It is therefore only necessary here to state the facts and summarise the history of the attempts as briefly as possible. Herring and other soft-scaled fishes cannot be transported alive at any stage of their existence. Handling is generally fatal to them. Therefore the only plan left open is to convey the ova. The eggs are adhesive, and under normal conditions are deposited on stones, gravel and other objects at the bottom of the sea in comparatively shallow water. The eggs hatch in about 16 days, the time being shortened or lengthened according to the temperature of the water; cooling causing retardation. The problem then was in the first place to retard development for a period of at least 50 days. If this difficulty can be satisfactorily overcome, there are several others which have to be met.

The first attempt was made in March, 1886, and was an illconsidered experiment, for no provision whatever existed for dealing

with the ova had they arrived at the Colony. The obtaining and shipping of the ova was entrusted to Professor Cossar Ewart of Edinburgh, who obtained between two and three million eggs from the Ballantræ beds off the coast of Ayrshire, Scotland, where the famous Loch Fyne herrings spawn. The ova were placed in large carboys and in wooden boxes with glass slides, which were fixed in stoutly made barrels filled with sea-water, and in this way were conveyed to Plymouth and placed on board the 'Ruapehu.' Professor Ewart had designed a special apparatus so constructed as to preserve through the entire voyage a steady quiet flow of pure sea-water over the eggs at an equable temperture of 33° Fahr. So far the experiment succeeded admirably, but owing to lack of foresight in the cooling apparatus, the pipes which were to supply the chilled water, instead of being surrounded with ice, were led directly through the refrigerating chamber. The result was that the water froze in them, none reached the ova, and by the time Madeira was sighted, all were dead.

The second experiment, also unsuccessful, was made by the Government in 1912. The Portobello (Dunedin) Marine Fish Hatchery was opened in 1904, and early in its history I had looked into the question of the introduction of the herring. The question of the retardation of the hatching of the ova again appeared to be the principal difficulty, and I entered into communication with Dr Fulton, Scientific Superintendent of the Scotch Fishery Board, with the object of getting experiments conducted at the Dunbar Hatchery to test this. Owing to the change from Dunbar to the Bay of Nigg, Aberdeen, and to pressure of other work, the matter was allowed to lapse, and it was not till 1908, this time at the instance of the New Zealand Government, that a series of experiments was commenced by Dr H. C. Williamson. The outcome of these experiments was that retardation of hatching of the ova for a period of 50 days, which we considered was the time required, was only successful to the extent of a small fraction of one per cent. Less than one in ten thousand survived such a long chilling. Both Mr Anderton, Curator of the Portobello Hatchery, and I considered that under the circumstances it would be a waste of public money to proceed further with the attempt to introduce the herring by this means. However the Government decided to make the attempt, and Mr Anderton was sent to the Old Country in 1912, to carry it out, while at the same time he took charge of a large shipment of turbot, lobsters and crabs. An ingenious apparatus for the conveyance of the eggs, and for the cooling and aeration of the water, was placed on board the Shaw, Savill & Albion Co.'s S.S. 'Waimana,' and was thoroughly tested beforehand. The

vessel called in at Plymouth, where Dr Williamson had secured about 60,000 ova adhering to glass plates. These were duly placed in the apparatus, and the voyage was commenced on 12th January. A fairly uniform temperature of 35°.5 Fahr. was maintained. On 24th January when the equator was crossed the ova were fairly clean, and the outline of the embryo could be easily distinguished. Some dirty water got into the boxes at Cape Town, and the sediment was removed from the eggs by means of a camel hair brush. By this time the chord and eyes were visible in all the live eggs. On the 6th February the plates were still in very fair condition, and then a mass of rust and sediment was forced through the pipes, and the eggs were thickly coated with sediment. The experiment was abandoned on 14th February when all the ova were dead owing to the state of the water. The ova were fertilised on 10th January. The majority contained live embryos on 6th February, 27 days after fertilisation, and some still contained live embryos on 12th February, 33 days after being fertilised. None of the ova hatched out.

The full report is worth studying, and it conveys a good idea of some of the difficulties encountered in this department of acclimatisation work.

Family SALMONIDÆ

The rivers and lakes of New Zealand contained originally a poor and rather sparse fish-fauna. It consisted of the grayling (Prototroctes oxyrhynchus), found mostly in clear rapid rivers, and a fine sporting fish; the smelt (Reptropinna richardsoni), common in rivers and lakes; several species of Galaxias, a mud-fish (Neochanna apoda), only found in the west coast rivers of both islands, two species of eel (Anguilla) and a lamprey (Geotria chilensis).

The kokopu, a name corrupted in the south of the South Island to cock-a-bully (Galaxias kokopu), was sometimes popularly called trout; it is a fat, sluggish fish which lurks under logs and stones, furnishes no sport, and is not particularly good to eat. The fish known as the minnow (Galaxias attenuatus) is, as its name implies, a small fish. According to the late Professor Powell, "White-bait is the fry of this species," but the facts want working out1.

The common eel (Anguilla aucklandii) is always with us, and is a very valuable food-fish, if people only knew it. The lamprey makes an annual visitation up the rivers in the spring months, usually about October.

1 In an interesting article on "Some Trout Fishing in New Zealand," which appeared in Blackwood's Magazine for March, 1918, pp. 365-77, Mr A. R. Chaytor states that New Zealand white-bait is the larval stage of the common eel. Anyone who has looked into the question of the development of the Anguillidæ knows that this is a quite mistaken idea.

Though there are altogether about a dozen species of indigenous fresh-water fish, yet to the early settlers of the colony, the rivers and streams seemed singularly empty. There was no sport for the angler, unless he happened to live near a stream where the grayling abounded, and except eels-which were abundant-there was practically nothing of an edible character to be found. It is not to be wondered at, therefore, that the minds of the colonists early turned to the idea of importing such fish as they knew would provide both sport and food. The success of attempts to introduce species of Salmonidæ into Tasmania and Victoria encouraged the hope that it would be possible to do the same in this colony, and in the sixties and seventies a systematic importation was commenced, not only by the Government, but by all the principal acclimatisation societies. Over a dozen species, or, counting varieties, about 17 kinds of Salmonidæ have been introduced into this country. The success of several of these has been phenomenal, but the failure of others to establish themselves has been inexplicable. The majority of the streams and lakes of both islands are now stocked with species of Salmonidæ, and an interesting problem has arisen, namely, are the species remaining distinct, or is there a tendency among the allied forms to hybridise and produce a generalised type? Another interesting problem faces both the angler and the naturalist. In a number of streams which are now heavily stocked with trout, the native aquatic fauna has been nearly exterminated, and the question of future food supply has been raised. Are new species of animals to be introduced, or can any method of renewing the indigenous fauna be devised?

I have dealt with the particulars of the introduction of the various species in some detail, but here I propose first to give some facts regarding the general question, and the early attempts to bring Salmonidæ into Australia and New Zealand. These show the difficulties which had to be faced in the early days, when transport was by sailing ships, and refrigeration was unknown. Mr J. Murdoch contributed an article, I think to The Field, but I have failed to find the date, on "The Introduction of Trout into Australia and New Zealand," from which the following facts are gleaned:

The first attempt to introduce ova into Australia was made in 1852 by Mr Borcius, who however failed, and lost £300 in the experiment.

In 1854 Mr Youl began to study the subject, and made many experiments. No hope of success was held out by the most experienced pisciculturists, and Mr Youl was told that he might as well try to fetch England to Australia as to carry spawn to it in moss. Mr Edward Wilson, President of the Victorian Acclimatisation Society, associated with Mr Youl and some influential colonists in obtaining £600 by

subscription. Thirty thousand ova were shipped in the 'Sarah Curling' on 25th February, 1860. The ice-house consisted of two rooms, one within the other, lined with lead; the space between was filled with powdered charcoal; a filled water-tank over the ice-house with a pipe leading into it allowed a gentle and continuous stream of water to pass over the ova as they lay in swing trays. The passage was long, the 15 tons of ice gave out, and the last of the ova was found to be dead when the ship was 68 days out.

Mr Youl then visited the fish-breeding establishments of Scotland and Ireland. He also made a series of experiments to test the vitality of ova at a low temperature. The experiments proved three, heretofore, unknown facts. First, that a continuous stream of water is not essential to the preservation of vitality; secondly, that partial deprivation of air is not fatal; and thirdly, that light is not essential. After these experiments he felt assured of success if a sufficient supply of ice could be preserved throughout the voyage.

In January, 1864, he again tried. Boxes were made (of inch pine) measuring twelve inches by eight inches by five inches, with perforated top, bottom and sides. At the bottom was first spread a layer of charcoal, next a layer of ice, then a nest of carefully washed moss, and on this spring cushion were deposited the ova. Over them was laid a covering of moss, then a double handful of broken ice, and the whole was saturated with iced water and screwed down. One hundred and eighty-nine boxes, containing 100,000 salmon and 3000 trout ova, were packed closely on the floor of the ice-house, and upon them were piled blocks of ice to the height of nine feet. The 'Norfolk' sailed on 21st January, 1864, and arrived in Melbourne on 15th April. The State of Victoria retained 4000 salmon ova, of which it is said 400 were hatched. The remainder were sent to Tasmania by a Government steamer. They were taken to the Derwent River, and placed in the hatchery provided. Mr Ramsbottom estimated that there were 30,000 salmon and 500 trout ova living. On 4th May the first trout was hatched, on the next day the first salmon, and by 25th May there were 300 trout and 700 salmon. At the end of 1865 the surviving salmon were allowed to enter the sea.

Of the 300 trout many died; about 30 were liberated in the River Plenty, while only six pairs reached maturity and spawned in the ponds. Their progeny have been liberated in many rivers and streams of Tasmania, Victoria, and New Zealand.

In 1866 Mr Youl brought out 87,000 salmon, 15,000 salmontrout, and 500 brown-trout ova. The result of this shipment was 6000 salmon and 900 salmon-trout being hatched from the 30,000 living ova which arrived. Other shipments followed, including brook-trout.