Amateur Fish Culture - Part 4
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Part 4

A few years, I might almost say months ago, the great majority of disinterested persons, whose opinion was of any consequence, were inclined to condemn the general introduction of this fish into our waters. I was, unfortunately, supposed to be among a certain cla.s.s of people who advocated the general introduction of this fish into all our waters indiscriminately. This, I have always said, was a very short-sighted policy, for, to begin with, the evidence at our disposal seems to show that the rainbow will never thrive in cold waters, and at the best can only be expected to really thrive and sp.a.w.n in the warm waters in the south of England. I never advocated more for the rainbow than that it should have a fair trial in waters where our own trout had been tried and found not to be a success. Now, however, I in my turn stand a chance of being converted by converts from among the very people who, a short time ago, were condemning me for holding too favourable an opinion of the fish in question. I am inclined to think that in the case of a pond in the south, even when it is supplied by a good stream, the rainbow is the better fish with which to stock. I have been led to believe this, partly through my own experience, and partly on account of the opinion of Mr. Senior, for I consider his opinion on such a matter of the greatest possible value.

Another point about the rainbow, which in many cases will recommend it particularly to the amateur, is that though of course an abundant supply of water is an advantage, it may be reared with a smaller supply.

A fish which has been very freely introduced into British waters is the American brook-trout (_Salvelinus fontinalis_). Though this fish is not really a trout but a char I have included it among trout, because it is so very generally known to fishermen as the American brook-trout. The _fontinalis_, as it is commonly called by fish culturists, is a very satisfactory fish to rear artificially, but there seems to be some doubt as to its suitability to British waters. It grows to a considerable size under favourable conditions, and is one of the best of table fishes. It is, however, undoubtedly one of the worst of cannibals among sporting fishes, and does not apparently rise freely to the fly when about two years old and older.

The sp.a.w.ning season is extended over an even longer period than that of our own brown trout, beginning, in its native country, in October, and sometimes lasting till March. It shows a very marked tendency, at any rate in America, to go down to the sea, and in some parts of Canada is called a sea-trout. The fish are easy to rear, but I should recommend great caution with regard to their introduction into any waters in England. The remarks and instructions which I gave with regard to the common trout, apply also to the _fontinalis_, but I would lay particular stress upon the necessity of separating the fish, as soon as some grow larger than the rest. The only drawback to this fish, from the fish culturist's point of view, is that though a very free feeder, it is very dainty, sometimes refusing a particular kind of food for no apparent reason. As the sp.a.w.ning season is extended over such a considerable period of time, it is obvious that the amateur will be able to obtain the ova, ready to hatch out, during a similarly lengthy period.

A fish which I should very much like to see tried in England, is the cut-throat trout (_Salmo mykiss_). It is also known as the red-throat trout. I should think, from the description given in the report of the Commission of Fisheries, Game, and Forests for the State of New York, that it would do well in many of our waters. There are many varieties of this species of trout. The common name of them all is _Salmo mykiss_, the black-spotted trout of the Rocky Mountains. The cut-throat trout proper, so called from the red colour of its throat, is simply S.

mykiss, but there are many varieties described. Among these are the Columbia River trout (_S. mykiss_, var. _clarkii_), the Lake Tahoe trout (_S. mykiss_, var. _henshawi_), the Rio Grande trout (_S. mykiss_, var.

_spilurus_), and the Colorado River trout (_S. mykiss_, var.

_pleuriticus_). As these names show, the black-spotted trout has a very wide range and is found in what are totally different climates. I should very much like to see the cut-throat and the Columbia River varieties tried in our waters, particularly the former, as they would probably succeed in waters which are too cold for the rainbow, and might very likely thrive where our own trout (_S. fario_) is not a success. As it is found in climates which vary so much as do Alaska and California, it would probably be easy to find one variety, if not two or three, which would thrive in England. It is a particularly fine trout, and the ordinary maximum weight is five or six pounds, though some of the varieties grow much larger.

Char, proper, are not at all satisfactory fish to rear. They are very delicate, and require much more care and attention than do any of the fish I have already described. From the very first period of their coming under the care of the amateur fish culturist, that is to say, from the ova, just before hatching out, till they are yearlings, the mortality among them will be much greater than in the case of any of the trout.

The two kinds of char, most commonly to be obtained by the amateur, are the Alpine and the Windermere char. The ova of these fish will be received shortly before they are ready to hatch out, as was the case with the trout ova. The amateur's difficulties will, however, begin almost at once, for in the act of hatching out considerable mortality among the char often occurs. Trout almost invariably emerge from the egg tail first. As soon as the tail is free the little fish begins to move it rapidly, using it as a propeller with which to swim about and thus soon works completely out of the egg. 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; but this is, of course, quite impracticable, unless there is some one constantly watching the ova, as the delay of even a few minutes will mean the death of the fish. This peculiarity in the hatching out of the char has also been observed by Mr. J. J. Armistead, and I have been able to verify it personally.

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 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.

Though there must be some doubt as to its success, I should like to see a really serious attempt at introducing char into some deep and large ponds in the south of England. Char have been very successfully reared in shallow water, which was certainly not kept at a particularly low temperature, so I see no reason why this fish should not do in some of our more southern waters. One drawback to the chance of this attempt being made, however, is that the char cannot be considered as being a fish which gives very good sport, and I very much doubt whether any one is likely to try the experiment simply to find out whether they would or would not succeed in the south of England.

CHAPTER XII

SALMON AND SEA-TROUT

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 sp.a.w.ning stage. This great mortality which occurs among the eggs and young fish when left to nature may be very considerably reduced by artificial means, so that a very fair proportion of the eggs deposited by the female fish will not only be hatched out successfully, but the little fish will reach the smolt stage safely and have a good chance of reaching the sea. How successful artificial intervention may be has been proved over and over again in the United States and in Canada. In the case of more than one river in Canada, the artificial propagation and protection of salmon has resulted in what is apparently the actual manufacture of a salmon river, yielding an annual haul of fish far beyond anything known in Europe, from a river which before yielded no salmon, or hardly any.

These operations, carried out by the State, were of course far beyond anything which could be undertaken by the amateur, but I am sure that if several riparian owners on a salmon river carried on artificial hatching and rearing operations for several seasons, a marked increase in the number of fish in the river would ensue. The objection of most people to this course is that it is unfortunately only too apparent that they are benefiting chiefly, not the rod fisherman, but the netsman at the mouth of the river.

The different artificial means used to help nature in producing a good head of salmon in a river vary chiefly in the amount of the help given by each. It will suffice to say that the best is that which provides for the protection and feeding of the young fish till it is ready to take its first journey to the sea. The reason of this is obvious, as every day pa.s.sed in safety is a day gained, both in strength and in power of self-preservation.

Though it is possible to purchase a certain number of salmon ova, this is not at all a satisfactory way of obtaining them. To begin with, it is impossible to get them in sufficient numbers to carry out operations on a large enough scale. Salmon ova are also expensive; and it is no use working with less than half a million in several stations if the river is of any size. It is advisable that the ova should be obtained from the fish. This may be done either by collecting the ova deposited by the fish in the sp.a.w.ning beds or from the gravid females. The latter course necessitates the ripe female and male fish being caught and artificially sp.a.w.ned. As in nature, at best but a comparatively small percentage of the ova are impregnated, and by artificial sp.a.w.ning over ninety per cent. of them may be successfully hatched out, there can be but little doubt as to which is the better way. It is difficult to make sure of catching the fish just at the time they are ripe, so it is advisable to impound them in a fenced-off portion of the river, where they may be got at easily.

In the ripe female the ova flow out very readily, and but little pressure is necessary. Hard pressure on the abdomen should never be applied, as it is sure to injure the fish. A ripe female having been obtained, from which the ova flow readily, the female is held over a perfectly clean tin or earthenware dish--wet, but containing no water--and the ova are caused to flow into it by gently but firmly pressing the hand on the abdomen, and stroking it down towards the vent.

Milt from a ripe male fish is then allowed to run over the ova in the dish, and is made to run well between them by tilting the dish about from side to side. The ova will now adhere together, and some water should be added. This water should be poured off and fresh added till the superfluous milt is washed away, when the ova should be left in the water till they separate, which will be in about twenty minutes or half an hour.

The fertilized ova thus obtained may either be laid down in artificially protected hatching beds, or may be transferred to a hatchery. The latter proceeding, of course, requires a hatching house specially built and arranged, and as this is outside the scope of the present work, I would refer my readers to larger works upon the subject, such as _An Angler's Paradise_, by J. J. Armistead. Of course, by using a hatchery a large number of the eggs will be saved, ninety per cent. of them should hatch out. This is, therefore, obviously the best way to proceed. A very much larger number of eggs will, however, be hatched out in properly-chosen artificial beds than would be the case if they were left to nature.

The necessary qualities of a good artificial bed are, a good supply of clean water which is not liable if there is a spate to deposit sediment on the eggs, protection from light, and protection from the many creatures which prey upon the ova. The hatching beds may be so arranged that the young fish may escape as soon as they like after hatching out, but it is best to watch and protect them for at any rate the first few weeks after they have begun to feed, and while continuing the feeding, to allow those of the fish that wish to escape.

The rearing of young salmon and sea-trout is practically the same as that of the common trout, except that they require more water. If kept in rearing ponds they grow more quickly than they do when left to find food for themselves. While young, the salmon is marked with transverse bars of a darker colour than the rest of the body. During the time it bears these marks it is known as a parr.[3] In about fifteen months it loses these marks and becomes quite silvery, being now known as a smolt.

Shortly after a.s.suming the smolt dress, the young salmon takes its departure to the sea. In some cases the young salmon do not appear to go down to the sea till over two years after being hatched out, but they should always be set at liberty in March, April, or May in the year following that in which they were hatched out, according to how far they have developed the smolt or silver appearance.

[3] All the trouts go through this stage, which is distinguished by "finger marks" upon the sides.

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. If hatching trays are not used, the bottom of the artificial bed should be covered with clean gravel.

The time which elapses from the impregnation of the eggs to their hatching out varies according to the temperature of the water, a fairly average time is about ninety days. The ova should be watched during this time, and the dead ones removed. For a short time after they are impregnated they are fairly hardy, but from then till shortly before they hatch out the very slightest concussion will kill or seriously injure them.

The management of sea-trout ova is similar to that of salmon, and the ova are obtained in the same way. As in the case of the salmon it is best to rear the little fish artificially, till they are ready to go down to the sea; they will thus escape dangers likely to cause the loss of about eighty per cent. of their number.

The same methods and the same precautions as advised in the chapters on rearing trout should be adopted in the case of salmon and sea-trout as far as is possible, and if this is done a very large percentage of the ova should be successfully reared to the smolt stage.

CHAPTER XIII

COa.r.s.e FISH

Compared to what is known about the early part of the life history of the _Salmonidae_, our knowledge of coa.r.s.e fish is small. 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 coa.r.s.e 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 coa.r.s.e fish in proportion to the supply of food.

I have seen many cases where rudd, perch, dace and carp have increased to an enormous extent from a few fish introduced into the water. Some four years ago we put a few small rudd into a mill-pond at home, thinking that the fry they produced would serve admirably as food to the trout which also inhabited the pond. In about twenty months the pond was full of small rudd, and last year we netted out many hundred, as the water was terribly over-stocked with them. The same thing has happened in almost every case which has come to my knowledge; that is, of course, where the waters have been stocked with food, and suitable to the fish introduced.

The way in which dace will increase when put into a suitable water is, if possible, even more remarkable than what happens in the case of the rudd. I will quote one instance, which proves this very conclusively. A few years ago there were no dace in the Suss.e.x Ouse. Pike fishermen, however, used to bring live dace to use as baits. Some of these escaped, or were set free by the fishermen at the end of their day's fishing, and now the Suss.e.x Ouse contains more dace for its size than any other river I have ever seen.

While rudd thrive best in a pond or lake into which a stream flows, dace require a river or stream to do well. They will, however, thrive and increase rapidly in a river where trout are not a success. A muddy bottom with occasional quickly running shallows, seem to const.i.tute the best kind of water for dace. The largest, and by far the best conditioned dace I have seen, have come from the tidal parts of rivers, where the water is brackish at high water. Dace from such a water have also the advantage of being very good eating, as they have, as a rule, not got the unpleasant muddy taste usual in this fish.

Perch and pike will thrive both in rivers and in ponds or lakes which have a supply of water from a stream or from springs. They both increase in numbers very rapidly, and when protected, are more likely to require thinning down every few years, than artificial a.s.sistance from the amateur.

The king-carp is the best fish for the amateur who wishes to obtain good bottom fishing from an absolutely stagnant pond. This fish is much bolder and a more free feeder than the common carp. It increases so rapidly in numbers, and is a hard fighting and lively fish.

Most of the coa.r.s.e fish deposit a much larger number of eggs than do any of the _Salmonidae_--that is to say, in proportion to their size. In stocking a water which contains no fish, the amateur may wish to hurry on the process of nature in the case of coa.r.s.e fish; and, fortunately, this is fairly easily managed. In the case of perch, rudd, pike, and carp, but little change of water is required to hatch out the eggs. The eggs of these fish take but a short time to hatch; and if they are protected, and this protection is also given to the little fish for a few weeks, it will generally be found that an amply sufficient result is obtained. The eggs should be spread out carefully on wicker-work or the lids of baskets and kept in the light. A trickle of water which is sufficient to change the body of water in the pond in which the ova are put will, as a rule, be enough. The amateur must be careful that the pond in which he hatches the eggs does not contain any of the many enemies I have described in former chapters. If it is at all possible to protect the eggs and the little fish, it is best to hatch out the eggs in the pond which it is intended to stock, for it is exceedingly difficult to keep the newly-hatched fish in a rearing-pond on account of their very small size. It will be necessary to use muslin or flannel screens instead of perforated zinc. Care must be taken that there is not too great a flow of water, as this will cause the little fish to be drowned at the outlet screen.

APPENDIX

THE USE OF EARTH IN REARING PONDS

[From a correspondence upon the subject which appeared in _Land and Water_]

SIR,--In your last issue I have read with pleasure the eminently practical notes on fish culture by Mr. Charles Walker. He is perfectly right in all he says with reference to the useful and preventive results of the use of "common garden" earth, or vegetable mould in checking any fungoid development, _Saprolegnia_ or other. It must, however, be admitted that the said addition is not an element of beauty in a box; therefore it should be avoided, or only used when necessity dictates.

However, the fry, when thoroughly restored to health, may be transferred by muslin net to another box free from earth should it be necessary to count out certain numbers for the satisfaction of customers' orders.

Again, the earth employed may, and in some waters does, give rise to other ill effects on the health of the "fry" or young fishes. Affection of the eye is not unheard of as the result of over-use of earth. Perhaps the best way to obviate any trouble of this nature would be to pound and dry the earth, and keep it in a canister or other closed vessel till required for use. Spores of fungi are nearly, if not quite, omnipresent; and their effects are so insidious that too many precautions cannot well be taken to avert the introduction of "trouble" in the hatchery.

Indeed, were it not for the risks arising from attacks of fungi, pisciculture, as now understood and carried on, would be an unalloyed pleasure and unbounded success. We can practically hatch 995 out of 1,000 eggs, or thereabouts. It is the risks of rearing that stand in our road, and these, as time goes on, and experience increases, must diminish. 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 circ.u.mstances, 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 antic.i.p.ate, and so remedy them. To be always on the watch and notice the first indication is a very safe maxim, more easy to inculcate than to put in practice.

There can be no question but that the practical removal of difficulties in the path of fish culture is work of the highest value, well worthy the attention and acknowledgment of those in authority at Whitehall and elsewhere at home, as has been the case abroad.

C. C. C.