Charles Edward Walker

“ If finely divided food is given in such small quantities that practically none of it sinks to the bottom without their having a fair chance at it, I believe that in a box containing only a couple of thousand fry, it would be found that they never stopped feeding during the whole day. If, however, too large pieces of food are offered to the little fish, many of them are likely to be choked and to die, from trying to swallow a piece a little too big for them. ”

“ Much of the existing literature of the subject deals with it on such a large scale that the amateur is frightened to attempt what is apparently so huge an undertaking. Fish culture may, however, be carried out on a small scale with success, and though considerable attention is necessary, particularly with young Salmonidæ, it is not a task which involves a very great proportion of the time of any one undertaking it. It is absolutely necessary, however, that the amateur fish culturist should live on the spot, or have some one who is intelligent and perfectly trustworthy who does. ”

“ There would appear, then, to be a good time coming for fish culture, and those who earnestly follow it.
Practice is the only safe guide, as circumstances, geological, physical, and meteorological so vary the conditions of works that no definite rule of procedure will avail. Earnest work and close observation, combined with ready resource, are the only safe guides to success. Troubles of some sort are sure to supervene; the man who succeeds is he who can anticipate, and so remedy them. ”

“ It is a very free feeder, and grows more rapidly than our trout; great care must therefore be taken to give it plenty of food. I would draw my readers' attention particularly to this fact as to the feeding and quick-growing qualities of the rainbow, for they make it, if possible, even more necessary that the water into which they are turned should contain a good supply of food than it was in the case of the common trout; though even in the case of the common trout, this is quite the most important consideration in stocking a water with fish. ”

“ The choice of a suitable spot in which to make his hatchery is a serious point for the consideration of the amateur. A spring is the best water supply as a rule, for the water is usually of a fairly even temperature, and does not require filtering, but water from a stream where trout are known to live is quite safe. A few years ago it would have been necessary for any one wishing to take up fish culture, to erect a building in which to place his hatchery if he intended to hatch any number of eggs, in order to guard against frosts. ”

“ Fresh-water snails are always desirable. In streams, or in ponds with streams running into them, the fresh-water shrimps (Gammarus pulex) should always be tried. It does not do in some waters, but where it does thrive it increases very rapidly, and forms about the best article of food that can be given to trout. Corixæ, which thrive in ponds and sluggish waters, should always be introduced. They increase rapidly, and are taken by most fish, particularly by trout. The amateur should be careful when he introduces these creatures to make sure that he is putting in the right creature. ”

“ Fortunately, however, such lengthy and complicated proceedings as are necessary to obtain a good stock of trout are not necessary to obtain a good stock of coarse fish. If even a few rudd, perch, dace, pike, or carp are put into water where they have a good supply of food to begin with, and which is suitable otherwise for their well-being, the amateur's chief trouble after a few years, if the water is not heavily fished, will be to keep down the stock of coarse fish in proportion to the supply of food. ”

“ Most people know that in our own country the monks had stew ponds, where they kept fish, principally carp, and also that the Romans kept fish in ponds. In the latter case we hear more often of the eel than of other fish. The breeding of trout and salmon, and the artificial spawning and hatching of ova, are, however, an innovation of our own time.
Much has been discovered about the procreation of fish, and in no case have scientists worked so hard and discovered more than in the case of Salmonidæ. Fish culture, particularly trout culture, has become a trade, and a paying one. ”

“ Having established the vegetable life well in a water, and developed it to a considerable extent, the amateur may begin to examine his water, and find out how much animal life exists there, and to stock with creatures suitable for food, according to what he finds in the water. ”

“ The rearing of trout is the most important branch of fish culture to the amateur, and fortunately but slight modifications are necessary in rearing other fish. What is good enough for trout is good enough for most fish, therefore I think that I shall be right in describing trout culture at considerable length, and dealing with other fish in a somewhat summary manner. ”

“ This is the effect of a spate—which is, after all, only a dose of earth—upon wild trout.
The mould should be mixed with water in a bucket, and, when the water is very thick and muddy, poured into the rearing boxes. The water in the rearing boxes should be so thick that neither the bottom nor the young fish, except when they come to the surface to take some passing particle of food, can be seen. The amateur should not wait till something goes wrong before giving this dose of earth; it is advisable to give it once a week at any rate, and oftener if the fish seem to be ailing in any way. ”

“ It may seem somewhat superfluous to say that fish cannot live in any water unless that water contains the food supply necessary for them to thrive upon, and yet this is the point most often overlooked in stocking waters with fish. Small attempts at stocking with creatures suitable for food, particularly after the fish have been already introduced, are not at all likely to succeed. ”

“ Ponds, particularly those which have a stream running through them, will, as a rule, support a good head of trout if properly managed. Again a water which contains trout may become more or less depleted, and here it is necessary to supply the deficiency of trout by some means. The easiest way is, of course, to buy yearling or two-year-old fish from a piscicultural establishment, of which there are many in the kingdom, but I know that there are many fishermen who would much prefer to rear their own fish from the ova, than to buy ready-made fish. ”

“ If suitable earth is used once a week, and even oftener on occasions, it can do no harm, and will keep the fish safe from a great many risks besides doing them very material good. I do not of course mean that the usual weekly dose should be a large one, as this would fill up the pond before the end of the season, but that a small dose should be given generally, and a large dose occasionally. I am quite sure, too, that clean earth with some nice weeds growing in it, looks better than gravel which is dirty. ”

“ In such rivers and in many ponds in the South of England I believe that no better fish exists than the rainbow trout. I say particularly in the south, because I do not think that the rainbow trout will ever really thrive and breed in cold waters. I have at other times given numerous examples which go to show that the rainbow will only thrive in warm waters. ”

“ Probably the best of all food for the fry is pounded shrimps or other crustaceans. It is, however, difficult in the very early stages of the trout's life to pound shrimps up small enough, and the little fish are much given to trying to swallow pieces of food which are too large for them to manage. This evil proclivity often causes the death of the fry, and therefore great care must be taken that no pieces of food which are too large, get into the rearing box. ”

“ In many ways nature is apparently very wasteful, and in nothing is this more marked than in the case of the salmon. Probably not more than one egg in a thousand produces a fish which reaches the smolt stage, and a still smaller proportion grows to the spawning stage. ”

“ The amateur who is beginning trout culture had better by all means buy eyed ova from a fish cultural establishment. There are many of these in the British Isles, and nowadays eyed ova are packed and sent safely all over the country. The artificial spawning of trout is not an undertaking in which the beginner is likely to achieve great success, and therefore I should advise him to avoid relying upon it when he commences his operations as a fish culturist. ”

“ But a small amount of thought will convince any one that in order that there may be a sufficient amount of animal life in a water, there must be an adequate vegetable life, for weeds are almost always necessary to the well-being of the creatures which serve as food for fishes. ”

“ Herons do a great deal of harm to fish ponds, even when the fish have got well into the yearling stage. I have on one or two occasions known of herons wounding trout of at least a pound in weight. Besides the actual damage they do by killing fish, they put all the other fish in the pond off their feed through frightening them. After a heron or kingfisher has been about a rearing pond the little fish will not feed for a considerable time, sometimes even for days. Notwithstanding their very evil proclivities, both herons and kingfishers are very interesting. ”

“ With regard to natural food, the amateur should take care to ensure a good stock for the young fish. Many of the creatures suitable for food may be cultivated in separate ponds at the same time as the fish, if a natural supply is not at hand. The Daphnia pulex (water flea) and the Cyclops quadricornis may be introduced into the boxes very soon after the fish have began to feed. Daphnia breeds at the rate which is almost inconceivable. The female produces her first brood of young when she is ten days old, and goes on breeding at an average of three or four times a month. ”

“ The mortality which occurs in the actual hatching out of the alevins does not, however, by any means end the trouble which the fish culturist has to encounter in the rearing of char. They require much more persuasion and care when they begin to feed and throughout the [Pg 80] whole of the summer. The percentage of deaths is always greater than in the case of the trouts, not excluding the fontinalis, which is, as I have already explained, not really a trout but a char. ”

“ The amateur should not forget, that though the little fish will stand a good deal of moving about as long as they are in water, they are likely to be killed, or at least severely injured, by a shock, particularly if that shock is sustained while they are out of the water for a second or two during their being moved from one place to another. ”

“ It is advisable to have as much grass as possible round the ponds, and such trees as willows and alders should also be planted round them. Willows and alder sticks planted in the early part of the year come into leaf in the same spring, and afford shade to the young fish in the summer. Some suitable weeds should also be grown in the rearing ponds. Water-cress, water-celery, water-lobelia, starwort, and water-milfoil, are all good. ”

“ Occasionally, however, trout hatch out head first, and in these cases the young fish generally dies before it can set itself free from the coverings of the ovum. Buckland observed that the alevins of the char very frequently hatch out head first, and consequently that many of them die before they can work themselves free from the eggs. If it were possible to have some one constantly watching the ova at the time that they are hatching out, it would be possible to save a very large proportion of them, as they may be very effectually helped out of the egg with a feather or soft camel's-hair brush ”

“ These water-bugs, though some of them are excellent food for even the small fish, will attack the ova, and therefore they should be kept out of the hatching trays. The fish culturist should, however, whenever it is possible, cultivate such of these water-bugs as are good food for the fry in separate ponds, as I have before recommended. The best of these water-bugs are Corixæ. Others, such as the water-boatman, water-scorpions and pond-skaters, are not of any value as food for the fish. ”

“ If spring water is obtainable, particularly if the water, as is usually the case, is of an even temperature throughout the year, the troubles of the fish culturist are considerably lessened. Without a building for the hatching troughs it is almost impossible in many places to guard against frost unless such a spring is available. Sediment may be avoided by putting frames covered with flannel at the inlets to the hatching beds, these will, if kept clean, prevent any sediment from coming into the ponds, and will allow plenty of water to flow in. ”

“ What I mean is, that when the habit of associating the appearance of a certain individual with a meal has been well established among them for a week or so, they should be allowed to escape from the box into the pond. ”

“ Unfortunately the trout is a little shrivelled, and the legs of the Dytiscus have been broken. D. marginalis lays its eggs in the stems of rushes. The larva, when hatched, makes its way out, and proceeds to lead a predatory life. The larva when full-grown is about two inches long, and is quite the most rapacious creature which lives in our waters. The adult beetle is also purely carnivorous, but is perhaps not quite so rapacious. It would, however, probably attack a larger fish.
The largest of English water beetles is Hydrophilus piceus. ”

“ An important matter to consider before turning the little fish out into the pond is, how the ponds are to be protected so that their many enemies may be kept away from the fry. Kingfishers, herons, and other creatures are very partial to young trout and will cause enormous destruction if not prevented. ”

“ Other birds, usually found on or near the water, are also likely to do much harm to the ova and young fish. Almost every creature which is found near the water seems to have a great liking for the ova of fishes. All the wading and swimming birds are to be dreaded by the fish culturist. They will, all of them, eat ova in enormous quantities, and many of them will also eat the little fish.
Besides birds, small larvæ of several insects will eat, or at any rate kill, the ova in considerable numbers. Caddis-worms are among these [Pg 62] larvæ which eat ova. ”