COPYRIGHT DEPOSIT: ; | le AGI. Lees SA ad Dah a The THE FARMER’S PRACTICAL LIBRARY EDITED BY ERNEST INGERSOL ~ FISH CULTURE BY WILLIAM E. MEEHAN The Farmer’s Practical Library EDITED BY ERNEST INGERSOLL Cloth 16mo _ Illustrated From Kitchen to Garret. By VurcInra TERHUNE VAN DE WATER. piplenaoreee Entertainments. By RENEE Stern, of the Congressional Library. Home Waterworks. By Carieton_ J. Lynpr, Professor of Physics in Mac- donald College, Quebec. Animal Competitors. By Ernest INGERSOLL. Health on the Farm. By Dr. H. F. Harris, Secretary Georgia State Board of Health. Co-operation Among Farmers. By Joun LEE CouLTER. Roads, Paths and Bridges. By L. W. Pact, Chief of the Office of Public Roads, U. S. Department of Agriculture. Poems of Country Life. By GEORGE S. BRYAN. Electricity for the Farm and Home. By FRANK KOESTER. Fish Culture in Ponds and Other Inland Waters. By WiuiLuIAM E. MEEHAN, Supt. Public Aquarium, Philadelphia. Village Improvement. By Parris. T. FARWELL. In preparation. The Satisfactions of Country Life. By Dr. JaMes W. Rosertson, Principal of Macdonald College, Quebec. In prep- aration. The Farm Mechanic. By L. W. Cuase, Professor of Farm Mechanics in the University of Nebraska. In prepara- tion. THE HON. WILLIAM E. MEEHAN. FISH CULTURE IN PONDS AND OTHER INLAND WATERS BY WILLIAM E. MEEHAN Formerly Fish Commissioner of Pentsylvania, Superintendent Public Aquarium, Philadelphia ILLUSTRATED Hew Work STURGIS & WALTON COMPANY 1913 @ CopyriGcnHt, 1918, BY STURGIS & WALTON COMPANY Set up and electrotyped. Published June, 1918 702008 fi 7 Or és t ©ChLA358158 WA) / CONTENTS CHAPTER PAGE I PoND-CULTURBE OF BLACK BASS . . . « « 3 II SPAWNING OF BLACK BASS AND CARE OF Fry . 24 III Rocxk-Bass, Catico-Bass, AND SUN-FISHES 49 IV Cat-FisH CULTURE 59 V Carp CULTURE , 70 VI WATER FoR TROUT CULTURE . 86 VII Trout Ponps AND How To Buitp THEM 93 VIII CoNnstTRUCTION or A TROUT-HATCHERY «2 IX TAKING AND FERTILISING Trout Eaes . . 126 X TrRovuT HATCHING, AND CARE OF Fry . . 138 | BEARING YOUNG TROUT). 5 UM oR a RS 160 tem ATLANTIO SALMON LS eg 174 XIII Hatcuine FisHes’ Eces In Jags ... . . 178 XIV CULTURE OF THE YELLOW PERCH . 188 XV REARING PICKEREL AND MUSCALLONGE . . 200 XVI Wuite PercH, Strirep Bass, SMELTS AND SucK- RAG at he eR ie ARO RD arse nN RE MRREITA | 5 XVII Frog CULTURE whe ae XVIII Makine AND MANAGING AN AQUARIUM ‘ia eee XIX THE CULTURE AND CURE OF GOLDFISH ene a LR On I ES es ee ee RE Re AR ‘ a a Bee ia ® 4 ‘a Pict Cae ce ie biisp io wth eget choy ES da) | ’ | mays Be) wanted Chat = ee a1 (8 48 a ER ; di ee jn io ea ay hy Wa A} ue A ROTEL ovate | ae i. i bas AAG somomchnae fu sah ah THOMA Mi, rt ) ieee eg, ee 3 SE euert end Covered Raceway. «0. sa « = « .« 104 Meeerout Hatching-frough 9. . - «6. 6 « + « « dI6® nC UTOUE Sette ok Owe ee al EOS CRman-Pickerel, in an Aquarium . . . . . « « « 200: Striped Bass (Roccus lineatus) . . . . . + + . S14 Common, or White, Sucker (Catostomus teres) . . . - 214 a a ‘4 4 NB ee | ‘, / \ ShP uk ui Fe: uy pas a 1 4) a ia ie i } ' y 5 ’ « w) rs * ‘ "> a oe “1% Py * « rrr ae a ” fs Pi \ i 4 é ’ ’ . * . . i ‘ « ’ . * 0 . ; * * * . . ¢ . ry ¥ ‘ . ? ‘ X ’ : re at * . . ty we i i t ry oi rey at NT f hal vei Mi if * CSE RY he iy a Aan MEST ith wih: MALL aR bi Ri Vag eee ie Carbiningn’s y ih abe Vee X's Li) (eli SEL BOR AE ef ee wal FISH CULTURE FISH CULTURE CHAPTER I POND-CULTURE OF BLACK BASS WHEN the propagation of bass was first un- dertaken in the United States, it was speedily discovered that it is impossible to express eggs and milt artificially from the ripe female and male. The handling of ripe bass produces a nervous condition which prevents their eject- ment, and affects even a fish taken from the nest in the act of spawning. Fish-culturists were then driven to resort to pond-culture; that is, to prepare bodies of water in which the fish might naturally spawn and hatch their young. Temperature and Volume of Water.—As bass naturally inhabit warmer waters than trout, it follows that water for a bass-cultural plant in the Northern States must not be directly from a spring or be of low temperature. 3 4. FISH CULTURE River, stream or lake water, which during the spawning season will not fall below 55 degrees, preferably below 60 degrees, and only becomes muddy after exceptionally heavy storms, and then for a short time only, is necessary. Dur- ing the breeding season, higher temperatures — than those named, and water perpetually clean, are very much to be desired. At 50 degrees the fish will not spawn; and at 45 degrees both eggs and fry will die. A great volume of water is unnecessary, al- though desirable, since it insures one against any fear of a shortage in drought. Under ordinary circumstances 500 gallons of water a minute will be ample to operate a very large plant, but, whatever the volume, it is of the utmost importance that it be under complete control. A fish-culturist who cannot regulate his water-supply is likely to lose two-thirds of his chances for successful work. Water that becomes roily through storms is not objectionable, provided the roiling is not continued too long or is of too frequent occur- rence, especially while the nests contain eggs. For a short time muddy water has no percept- POND-CULTURE OF BLACK BASS | 5 ible effect on fry, or advanced fry, and is bene- ficial to mature fish. As a rule the best water for both kinds of bass is from a stream draining a lake. It is even more desirable when taken directly from the lake itself, because it is better aerated and probably contains more plankton, or minute surface forms of animal life which are essen- tial as food for advanced fry and young bass, and which are taken unconsciously by the large fish. Next to water flowing from a lake is stream water which is not too frequently spring fed; and after this in value is river water. Choice of Site—Three conditions are neces- sary as a basis for successful cultivation of small-mouthed bass; a favourable site, properly constructed ponds, and suitable water. Nearly all other problems which may and will arise are either subordinate or sequences. When seeking a suitable site for bass-ponds, a decided pitch in the ground is not vital, as it is only necessary to have sufficient for complete drainage. A relatively large area of ground is required if many thousand young fish are to be fed, say at least 25 acres. A pond of half 6 FISH CULTURE or three quarters of an acre cannot be expected to yield more than 100,000 young fish, even with a suitable number of accompanying fry-ponds; indeed, not more than 50,000 or 60,000 could ordinarily be expected. Character of the Bottom.—When the small- mouthed bass seeks a site for a nest it al- most invariably selects a gravelly or rocky bot- tom; but this is about the last selection the ex- perienced bass-culturist will make for his pond. His first choice would probably be a heavy clay. through which water cannot percolate, or a spot where the bottom can be made water-tight by puddling it with clay. A stony or gravelly bottom is not desirable, at least for breeding- ponds, because the fish-culturist cannot have absolute control over his brood-fish, as it would be impossible to force them to use artificial nests. Mucky ground for smallmouth-breed- ing should be avoided, because in moving about the fish are apt to keep the water muddy, thus preventing frequent observation,—a very im- portant feature in bass-culture. Swamp-land is worthy of very favourable consideration, be- cause, while the surface is apt to be wet and POND-CULTURE OF BLACK BASS soggy, the underlying material is likely to be clay or heavy loam, impervious to seepage. On the size and character of the gravelly spots or muck-holes in it must rest the availability of such property for the purposes of bass-ponds. A pond cannot be built over a muck-hole of any considerable depth. Dams and Reservoirs.—A. wise man will not build a pond for breeding bass by throwing a dam across the stream which supplies the water for his establishment. There are cogent reasons for not using the bed of a stream for such a purpose, among which are the fact that the water-supply is beyond the ownér’s con- trol, and in case of heavy rains he stands a good chance of losing his entire stock. Not having entire control of the supply, the fish- culturist would also be at the mercy of varying conditions of water-temperature. Further- more, mud is almost certain to gather in the bottoms, and there is danger of eggs being smothered by it. All ponds for a bass-cultural plant should therefore be built to the right or left of the supplying stream, and the water let into them 8 FISH CULTURE by pipe or sluice, arranged as is recommended hereafter. The first work to be done is to make such arrangements as will insure the easy flowing of water from the sources to any part of the grounds. If the fall in the land is sufficient, a pipe of adequate size may be laid in the creek at the upper end of the grounds, or above them, so that the water can be carried to the pond by gravity. When such piping is not feasible, a dam must be built at the upper end of the prop- erty high enough to carry the water where de- sired. What may be called the reservoir, or supply-dam, should not be solid from shore to shore, but have a wide sluiceway at the chan- nel-point, closed by splash-boards or gates, which may be removed or opened during freshets to carry away the surplus water and maintain the reservoir at as nearly a normal height as possible. Where it can be done, an ideal plan is to establish a regular reservoir at the upper end of the establishment, where the water can rest awhile, subside and breed plankton, and from which the supply for the hatchery can be drawn. ‘SSVad-adOOUd YOHX GNOd IVHCI ‘2 ‘“HSIUNOS YO SSVA MOVIE YOX SGNOdG-YDNIGHAUA ‘T ; f oy Live as ny “ 7 a : ai. | : 8 Si A es : . ren : aay. te ae ee POND-CULTURE OF BLACK BASS 9 Concrete is the best material for dams across a stream, but whether built of concrete, timber or masonry, the lower face should not be per- pendicular, especially if the stream is large or its volume frequently changes, for if it is the falling water will rapidly wash a big pool at the base of the dam and is apt to cut under the foundation. To ensure permanency the lower face of the dam should be sloped, either un- brokenly or in a slightly reversed curve from the crown. The curved construction is the most approved form to prevent pool formation and undermining. Construction of Ponds.——Ponds for black bass may be dug below the surface of the ground or built above it to accommodate the pitch of the land, the fancy of the owner, or the reputa- tion of the supplying stream for flooding. If the land is flat, and the water to be introduced by means of a dam across the stream, naturally the ponds will be dug below the surface, and perhaps in addition will need sides built up for some distance above. If the land has a decided pitch, then the natural course will be to build the ponds entirely or almost entirely above the 10 FISH CULTURE surface. Such construction may be considered as ideal, because perfect drainage 1s then cer- tain. Earlier bass-culture was conducted in ponds of very small dimensions, but with advancing experience the area for breeding-fish was in- creased, until now some almost approach the size of lakes. Few now in use for breeders are less than 200 by 75 feet; and the tendency is to make them much larger. Four to five acres, however, is about the limit that can conveniently be cared for; and those who breed bass feel that even that space can be more satisfactorily handled, and with better results, when divided into two or three breeding-ponds than as a single body of water. Owing to the expense of constructing very large ponds, and the length of time required for their completion, it is ad- visable when starting a bass plant to build one or two ponds about 300 by 100 feet in order that there may be an early stock of young fish. Depth and Bottom.—The bottom of a pond for fish-cultural purposes is divided into two parts, one called the ‘‘kettle,’’ and the other the ‘‘spawning-shelf,’’ or simply ‘‘shelf.’’? The POND-CULTURE OF BLACK BASS 11 first is an area at the outlet end of the pond deeper than the shelf and intended as the winter quarters of the bass. The second is the area in which the bass spawn and spend the greater part of the year, and is the shoalest part of the pond, as well as of the greatest extent. Some culturists prefer to construct a bottom which slopes gradually downward from the upper or inlet end to the lower or outlet. Un- -questionably fish seem to do as well in a pond of this character, and it does not necessarily mean a loss of the spawning area. Bass often build their nests in from six to eight feet of water, although in such instances it is usually late in the season. Ponds with a sloping bot- tom throughout are not nearly as easily handled and cared for as those in which the water over the spawning shelf is approximately of even depth. One desirable feature is the greater ease with which the action and progress of the fish may be watched during the spawning period, or at any other time. Close observation of bass is essential during the height of the spawning season. At times there will be fresh- ly laid eggs, eyed eggs, eggs just hatched, fry 12 FISH CULTURE freshly hatched, fry collected and ready to rise towards the surface of the water, all at the same time. Fry have been seen at nine oclock in the morning tight against the bottom, and at three o’clock in the afternoon swimming near the sur- face. On occasions fry may be hugging the stones on the nest, and half an hour later be © swimming freely two or three inches above the bottom. In deep water or on sloping bottoms, movements of the fry are apt to escape notice. Before the culturist is aware of it, he will find the edges of his pond black with advanced fry which have escaped being impounded, and which he will find extremely difficult to capture in their entirety. Sides and Outlets—Ponds with sides of natural earth are better than those with sides constructed of concrete, stones or boards. Be- sides, the cost of artificial walls would be so great as to be almost prohibitive. The only drawback to the natural earth is the proneness of muskrats to pierce them with holes, which de- stroy the banks and often allow water to escape. The sides of a bass-pond should always be BASS HATCHERY AT MILL CREEK, MICH., SHOWING RE- TAINING-WALL TO PREVENT FLOODING. POND-CULTURE OF BLACK BASS 18 sodded to the water’s edge, both for beauty and for the encouragement of grasshoppers and crickets, which will occasionally fall into the water and furnish food for the fish. There should be a valve or regulating board at every water-intake, so as to guage and control the quantity of water used. The inflow-pipe or sluice ought to be carefully screened, in order to prevent the entry of any undesirable water- life, as eels, and mud-puppies (otherwise known as water-dogs or hellbenders) either of which can do considerable damage. The outlet of the brood-pond may be by splash-board or pipe, but whichever is adopted it must be enclosed by screens, to prevent either mature or small fish from escaping. The desirable place for the outlet is the centre of the breast of the pond. It is also very important that arrangements be made by which the water can be drawn off gradually when desired, so as not to create a suction sufficient to carry out of the pond any small fish, which may have escaped from cribs or pounds. Brood-ponds should contain aquatic plants, such as -the common water-lily (Nymphia 14 FISH CULTURE odorata). During hot summer days bass love to lie underneath the shade of its leaves, but care must be taken not to permit the plants to gain such a strong hold as to clog the pond and prevent free work. Quarters for Fry and Fingerlings.—Ponds for the exclusive use of the advanced fry or fingerlings of bass are just as necessary as ponds for brood-fish. It is difficult to have too many ponds. It is recommended that there be not less than five fry-ponds for every brood- pond of about ten thousand square feet, and each of considerable area, with a combined area equal at least to that of the brood-pond. The more room there is for the advanced fry and fingerlings the less will be the amount of canni- balism. A large number of medium-sized ponds for advanced fry and fingerlings, instead of one or two large ponds, is preferable, because it is es- sential to control or closely supervise the fish, which cannot be done if the body of water is very large. The dimensions of the fry-ponds will be governed by the available ground, the quantity of natural food which can be bred, POND-CULTURE OF BLACK BASS 15 the convenience of handling, and the number of fish to be placed therein. Again, it is emphasised on general principles that the smaller the number of advanced fry placed in a rearing-pond, the greater will be the percentage when the period arrives for their distribution. A pond of less than 30 by 20 feet ought not to be considered for a moment, since it would hardly rear 2,000 fish to be two months old, probably much less. About 2500 square feet, carrying approximately 20,000 advanced fry to the age of thirty days, or the fingerling stage, may be considered as a minimum. The depth of water in the fry-pond is an im- portant consideration. Young bass being rapid growers during the first few months, in order that they may develop freely and quickly should have the highest temperature of water naturally obtainable, so long as it does not ex- ceed 85 degrees. It is for this reason that fry ponds for bass are seldom more than two feet deep, with a minimum of 12 inches, and with a kettle at the lower end to facilitate the use of a net when the water is drained off to take out the fish. 16 FISH CULTURE The shape of a fry-pond is immaterial, pro- viding there are not many angles to prevent quick and easy seining; yet it is an economy to have fry-ponds longer than their width, so that they may be more easily seined, since the method is to seine them lengthwise and not across. Fry-ponds are to be located as close to the breeding-ponds as possible, chiefly on account of convenience in transferring, and close to- gether, so that when sorting takes place the different sizes of fish may be quickly changed from one to another. If there be any consider- able number they should be divided into groups, each with a separate drainage system, and a separate water-supply; for, as high tempera- tures are necessary, such waters lose their health-giving qualities very rapidly. As soon as possible ponds enough should be built to have two complete sets for use in alter- nate years, so that while one set is used the other can be drawn entirely clear of water from September until March. ‘Two sets of ponds will be found useful also because of the rapid growth of aquatic plants, an essential feature POND-CULTURE OF BLACK BASS 17 of a brood-pond. The drawing off of water en- tirely from September until March is desirable because it encourages the growth of plankton, an essential feature in successful bass-culture, and also because it destroys the larve of the dragon-fly, and of water-beetles, the water- beetles themselves and the crayfish, all destruc- tive although furnishing food for the fishes. Finally, the periodical drawing off of water as- sists in keeping alge in check,—one of the greatest nuisances known to fish-culturists. Introduction of the Stock.—For some years it was universally believed that mature bass must, under all circumstances, be intro- duced from their wild habitat into the hatchery in the autumn, to insure their spawning the fol- lowing spring. An impression prevailed that the fish required time to accustom themselves to their new environments, and to recover from the excitement or terror of capture and trans- portation. Those who entertained this view may have acquired it from the knowledge that some- times, after abortive efforts had been made to express eggs from a ripe female, she was un- 18 FISH CULTURE able to perform that function herself. But the experiences of Dwight Lydell, and of the late Frank N. Clark, two authorities on the culture of small-mouthed bass, and the observations of others, seem to show conclusively that neither terror nor excitement can be taken as an explanation. Moreover, the same authori- ties demonstrated that small-mouthed bass may be introduced into hatchery ponds in the spring and spawn the same season only when intro- duced not earlier than ten days before the regular spawning period. It is therefore a hazardous procedure to depart from the prac- tice of autumn introduction in the case of the smallmouth. The spawning habits of the largemouths, on the contrary, do not seem to be affected or disturbed in any manner by the time of their capture. Whether caught in au- tumn, early spring, or when ripe, seems to them a matter of indifference, for when the breeding season arrives they follow the in- stincts of their nature and fulfil the function of reproduction. A cautious bass man will put off securing his supply of mature fish in the fall as long as he POND-CULTURE OF BLACK BASS 19 ean safely do so. If he captures them while the water is yet warm he is likely to lose many of his best specimens through fungus. Be- sides that, he does not want to begin taking care of a lot of fish and providing food for them until he has to do so. If the fish are in- troduced in the fall, as it is impossible at that time to distinguish sex, it is better to have more than needed. The trouble and cost of caring for any surplus during the winter is trifling. When spring arrives, and the fish develop to the point where the sex can be determined, sorting must begin and continue until the requisite number of males and females is secured. Feeding Mature Bass—For a day or two after wild mature bass have been placed in a breeding-pond it is not worth while to at- tempt to feed them. It is better to allow them a little time to grow accustomed to their new quarters, and also to become quite hungry. One of the difficult tasks to accomplish is to induce small-mouthed bass to take other than live food, especially when there are no domes- ticated fish already in the pond; if bass are 20 FISH CULTURE already there the work is greatly simplified, because the new comers, seeing the ‘‘oldsters’’ rush forward to the meal, are more likely to do likewise, if only to gratify their natural in- stinct to keep their fellows from getting any- thing they can possess for themselves. Bass-culturists naturally resort to beef lungs and liver if live food cannot be furnished. Some believe it essential to cut these into slices about the bigness of one’s little finger, so as to make the pieces somewhat resemble worms or fishes, and give them a wriggling mo- tion as they sink, deceiving the bass into think- ing that they are alive. The experience of others shows that the energy expended in doing this is unnecessary, for small-mouthed bass can be induced to take lungs and liver cut in an ordinary meat chopper through the largest perforated plate, if time and patience are ex- ercised. As soon as smallmouths have be- come used to this food, they will eat it as readily and eagerly as trout. Bass, even in ponds, do not school as closely or move with the same speed as trout, there- fore artificial food must not be thrown at them POND-CULTURE OF BLACK BASS 21 as rapidly or in the same manner as when feed- ing trout. At the outset, when teaching bass to take lungs and liver, only a piece or two at a time should be cast into the water, and then by the hand and not by means of a dipper or spoon. If the pieces can be thrown so as to cause them to skip a little, the chances of the fish taking them will be greatly increased. When feeding the first few times, mixing with it a few minnows will induce the fish to take the artificial food more readily. The best plan is to throw two or three little strips of lung, then a minnow or two, and immediately after a few more pieces of meat. Mature bass may become accustomed to the artificial food in a week or two, but the cul- turist need not lose heart if at the end of five or six weeks they have not yet brought them- selves to feed upon it. Efforts must be con- tinued, for sooner or later, success will be achieved. It will be a great aid if the feeder makes a practice of casting the food upon the water daily from the same spot on the bank of the pond, for fish soon become accustomed to their attendant and his ways, and if they are 22 FISH CULTURE hungry hasten to the customary spot when he appears in the hope of getting something to eat. One fish-culturist never passes his feed- ing-place without throwing some small objects into the water, even if it is only a handful of pebbles. The consequence is that whenever he appears there is a rush of fish after him and they will almost take liver from his fingers. Minnows.—Small-mouthed bass grow sleek and healthy on liver and lungs, although it is admitted that minnows and crayfish, if they can be secured, are the best food that can be given. It is surprising what a quantity of minnows a few bass can devour and digest in a very short space of time. One hundred ma- ture bass can readily dispose of 800 of the small fishes without any trouble whatever in an hour, when fed to them two or three at a time. It is not advisable to furnish so many, however, for if the bass average two apiece, per day, they will not starve. Neither is it well to feed them in such a way that by the time the assistant is through all the minnows have disappeared. Some advocate feeding one half the number allotted for a meal, two and POND-CULTURE OF BLACK BASS 23 three at a time, and then casting in the re- mainder at once. It is argued that by this method many of the minnows will escape for the time being, and keep the bass busy for half a day or more hunting them. This search- ing for the food some men declare to be bene- ficial. There is one important exception to this rule, however, namely, that just before the spawning time the minnows must be thrown in one at a time and eaten before another is tossed in. It is inevitable that some nests will be stolen and some may escape observation. When this is the case, if there are any number of minnows at large in the pond, they will have the time of their lives when they come upon the young bass. They know their opportunity and will seize it. They are much larger than the bass-fry, and a hundred or two healthy minnows can easily devour several thousand fry in two or three days; hence there must be no minnows alive and free in the breeding- pond at spawning time. CHAPTER II SPAWNING OF BLACK BASS AND CARE OF FRY Havine considered the character of the pond, the quality and volume of the water-supply and its disposition, the next important point for presentation is that of the nests and their adjuncts. Bass nests in a hatchery are of two kinds: those provided by the culturist, and those which the bass themselves make. Artificial nests consist of a box containing coarse gravel. The size of the box is some- times determined by the size of the fish in the breeding-pond, but ordinarily it is two feet square, with two sides open. The bottom is fitted with two strips, three to six inches wide. The thicker the strips, the deeper the bed of gravel. The top of the box is provided with a board to strengthen it, and on which to place a weight to keep the apparatus steady in the 24 s Salmoides). U r ASS (Micropte ACK B LARGE-MOUTHED BLACK B ASS (Micropterus Dolomieu) MOUTHED BL SMALL- SPAWNING OF BLACK BASS 25 water, as well as to act as a sunshade to the fish. A spot several inches deep and two feet square is excavated in the pond, the box is placed therein, and the hole filled with gravel, varying from the size of a goose-egg to that of a marble, to the top-level of the strips. It is policy to place some of the large stones in the centre, as a bass would do if it were construct- ing the nest. It is the male that selects the site for the nest and gets it ready for use. He does this before he has even looked about him for a mate. If he has started early in the season, say the latter part of May, while he is yet un- ripe or ‘‘hard,’’ he sometimes digs for days before the nest is completed to his satisfaction. Construction of the Natural Nest.—The nest-building season begins usually about the middle or latter part of May and sometimes does not end until after the first week in July. As a rule the site for a nest is selected with great care and with close attention to sur- rounding conditions. Bottoms with small loose stones, or with gravel or clean sand, are invariably preferred. Places with large rocks 26 FISH CULTURE or immovable stones are generally avoided. Early in the spring nests are located in shal- lows where the water is likely to catch the warming rays of the sun earliest and receive them the longest, but nests will often be located in places shaded throughout the day; and to- ward the close of the season they may be con- structed in seven or more feet of water, doubt- less because the shallows have become too warm for the proper hatching of the eggs. Wherever possible, a natural nest is placed in close proximity to a large stone, a sunken log or some other submerged object, which will protect it from being violently washed by the water in stormy weather. A site selected, the male bass clears away the mud and débris from a circular space, by ex- ceedingly rapid fanning motions of the pec- toral and ventral fins, and by slower sweeps of his tail. Leaves and sticks are carried outside the enclosure in his mouth. Stones and pebbles are pushed into place by means of his nose. Usually a slight concavity is noticed in the natural nest, and should be imitated in the artificial one. Sometimes a natural nest is SPAWNING OF BLACK BASS 27 found almost perfectly level, due it is believed to the rapid ripening of the male, which pre- vents his completion of the work. If he is nearly ripe, he is less likely to spend much time in construction, but devotes himself rather to thoroughly cleaning it and to working the larger gravel to the centre, the two most im- portant considerations. The larger stones are centred in the nest because it is among them that the bulk of the eggs are to be deposited. Courting the Female-—When his house is ready, the male bass seeks a female and pays court to the first that he meets. He does so without ascertaining whether or not she is ripe, reserving for himself the privilege of reject- ing or divorcing her after she has been to the nest and proves unripe. On encountering a female he begins the most grotesque contor- tions. He will swim around her in erratic circles, will nip her gently on the cheeks and belly, rub against her and show himself off, in his way, just as proudly as a cock bird does when courting a hen. All the time he guides her steadily towards the nest. At times she appears to* accompany him willingly; then 28 FISH CULTURE again she displays indifference and even re- luctance at accepting his advances. When at last he has succeeded in coaxing her to the nest, it seems as if the coquette regarded his work of nest-building with scorn or contempt. She is apt to swim languidly several times over the nest and then leave it, to the evident perturba- tion of the male, for he redoubles his antics and contortions, exhibiting as many as a negro in a ‘cake walk,’’ and guides her back again to the nest. This courting sometimes continues for two or three hours before the female consents to remain. Then if he finds she is hard, and the egos cannot be expressed, he promptly drives her away and goes in search of another female, to whom he pays as assiduous court as he did to the first. Should she prove ripe, the func- tion of spawning is begun. If much delay oc- curs in meeting a ripe female, he does not accept the fact philosophically, but ‘‘runs amuck.’’ He darts hither and thither over the pond, and at the first nest in which he discovers a ripe female, there ensues at once a free fight. The raging bachelor dashes into the peaceful SPAWNING OF BLACK BASS ~— 29 household, and does his best to thrash the male owner and appropriate his mate. It is a bat- tle often to the death, a struggle in which no quarter is desired nor given, and in which the female is apparently an uninterested specta- tor, ready to accompany the victor. Whatever the outcome, the nest is nearly certain to be destroyed. On account of the propensity of the male to go to war when unable to find a ripe female, it is consid- ered best by some not to stock a breeding-pond with pairs, but to introduce females in the proportion of about five females to three males. The surplus is not lost, because it often happens that a male will nest a second time, if he comes upon a ripe female after he has hatched out the first lot of young and discards them. All fish-culturists, however, do not advocate or practice having the sexes in the proportion of five females to three males. On the contrary, the majority probably pair the fish evenly, and assert that no ill effects have ever followed doing so. It is a curious fact that no matter how many nests there are in a pond every male is able to distinguish his own from his neighbour’s. A male may be removed from the nest at one end of the pond, taken to the other and liberated, yet, even if the distance is a mile or more, it will not be long before he will be found 30 FISH CULTURE back again oft the nest he constructed. To prove this fact it is only necessary to catch a male, mark him and liberate him at once. While the black bass is usually satisfied with one female, monogamy is not an invariable habit. It is said that sometimes a male, seeing a female passing the nest, although he already has a mate, will rush out and bring in the stranger, and add her to the household. It is also said that occasionally, for some reason or other, before the female has finished ejecting her eggs, the male will become dissatisfied with her, drive her away and bring in another mate to take her place. Again, if a female is not attracted by the par- ticular male, he will sometimes have great difficulty in inducing her to remain. She will make efforts to escape while he is doing all in his power to keep her. Sometimes she succeeds in getting away, and mates with another male, but rarely without a terrible battle in which she may lose one or more of her fins, or be otherwise injured. It is possible that when the female is dissatisfied, 1t may not be due to a lack of attraction on the part of the male, but that she is not suited with the nest, particularly if it is restricted by an arti- ficial box. Behaviour when Spawning—The act of spawning and impregnation is exceedingly in- teresting. The male and female pass each other in opposite directions, pressing their SPAWNING OF BLACK BASS 31 bodies together, and thus assisting each other in voiding the eggs and milt which issue almost simultaneously, the eggs possibly an instant ahead of the milt. If the eggs do not come freely, the male will sometimes go to the length of pressing the abdomen of the female with his mouth, she working her tail rapidly as if to loosen the tissues; indeed, frequent and plainly visible tremors shake both male and female from head to tail throughout the entire process. The female does not yield all her eggs at once. The larger the fish and the warmer the water the greater will be the number of eggs deposited at a single spawning. As a rule, one period of spawning covers about half an hour, but even then there is not an uninterrupted flow of eggs; they issue in little spurts or jets, from 30 to 60 seconds apart. There may be, also, intervals from three to five minutes, dur- ing which the pair swim around the nest, coquetting with one another. At the end of half an hour there is a cessation of egg-laying, of indeterminate length, depending on the temperature of the water and upon the condi- tion of the,female. As a rule, two or three 32 FISH CULTURE days elapse before all the eggs are deposited. As soon as all the eggs are laid, the male drives the female away and assumes full charge of caring for the eggs and hatching them. He moves slowly back and forth a few inches above the nest, with intervals for rest of perhaps a minute, keeping his pectoral fins moving all the time, so as to fan away all dirt or sediment, and often raising his body to an acute angle so as to bring the fanning tail-fin closer to the eggs. Every few minutes he will carefully scrutinise all parts of the nest, to make sure there is no dirt anywhere; and will make short excursions to see that no enemies nor curious fish are approaching too near. During this period he exhibits marked savagery,—seems to have lost nearly all sense of fear. At such times a bass has been known to rush fiercely at a man’s hand thrust into the water, and bite it with all his might. After the eggs have hatched, and when the culturist is dipping the advanced fry from the nest, it is not uncommon to have the old male rush at the net and sometimes tear it. It is unsafe for any fish to approach a nest while it is occupied SPAWNING OF BLACK BASS 33 by eggs or fry, for a bass will not hesitate to attack a fish three or four times its own size, and will invariably succeed in driving it away, . unless, as before described, it is another black bass, one on a rampage for a mate. A bass of one and a half pounds will put to flight two or three carp of twenty to twenty-five pounds’ weight. Bass which have been kept in breeding-ponds. lose to some extent, in course of time, the viciousness they display in a wild state when spawning. Seeing mankind as often as they do, and receiving food from their keepers regularly, the fish become domesticated, and the regular attendant, if he moves quietly, can go around the pond and attend to his work without disturbing them. Still, it is always better at spawning time to approach a nest only when necessary, and then in the quietest and most inconspicuous manner possible. Domestication of bass never extends to a point where the male views a disturbance of his nest with resignation. While not always as vicious as when in a wild state, he will often display strong anger and bite a man’s bare legs if he — 384 FISH CULTURE wades into the water, or strike at his hands or at the net when the nest is being tampered with. During all the time of building the nest and watching the eggs, and until long after the little fish are hatched, the male bass does not usually take any food. If food be dropped into the nest he will pick it up and throw it outside. It is said to be a fact that if a fish has been killed, or for some reason driven from the nest while the eggs are still un- hatched, and another male comes along ‘and takes possession, instead of assuming charge and hatching the eggs as he finds them he will simply treat the eggs as dirt, clean the nest, and bring in a female to deposit a new stock. Another curiosity of the spawning period is the frequency with which a male will select for his mate a female much larger than himself. Out of forty-seven nests which I examined in one natural pond, two-thirds of the males were much smaller than the females; and, as a rule, a female bass is larger than a male of the same age. Except for a short time before spawning actually begins it is extremely difficult to dis- SPAWNING OF BLACK BASS 35 tinguish the male from the female,—indeed most fish-culturists say it is impossible to do so, in spite of the contrary belief among fish- ermen. Just before spawning time the females are rounder in outline than the males. Barrenness occurs to a greater or less extent among all fresh-water fishes, but this does not imply that a female will be barren throughout her life. Some may be barren one year and never again until there comes what may be called a ‘‘change of life’’; or barren for two or even three successive years, and then produce good eggs. Intermittent barrenness is more common among introduced fishes in captivity than among wild indigenous species. One of the most conspicuous ex- amples in the eastern United States is the rainbow trout, of which half of the females in a single pond have been barren in one year, and at the same time half of the males were either without milt, or yielded infertile milt. This, however, is merely an illustration of a well known law of nature, that changed environ- ment is likely to produce sterility in animal life. Preference for Natural Nests—Many men urge that artificial bass-nests should not be placed nearer together than ten to fifteen feet; and that the boxes ought to be so arranged that the fish on one nest cannot see the fish on an- 36 FISH CULTURE other; yet in particular cases, where it was necessary for the nests actually to face each other, no trouble was experienced. Moreover, a number of bass have built natural nests im- mediately outside and against the boxes of some of the occupied artificial nests, and were not disturbed. Several other fish built natural nests close together and appeared to get along well. This becomes more significant from the fact that these bass were not domesticated in any way, but were wild fish caught during the spring in Lake Erie, and introduced into the breeding-ponds, where they built nests and spawned a few days after their arrival. In every pond fish will be found which ab- solutely refuse to make use of nests prepared for them, however carefully constructed, but will build their own, sometimes of inferior con- struction. Some bass have, on occasions, carried their apparently obstinate rejection of an artificial nest so far as to scoop out a hole in the muddy bottom, in which unfavourable situation eggs were deposited and hatched. Often the natural nests are larger and con- tain more eggs than those which are artificially SPAWNING OF BLACK BASS 37 built. A skilled bass-culturist in commenting on this peculiarity said: **In the use of the artificial or box nests, it is pos- sible that the female selected by the male may be an extraordinary fish. In their maneuvres back and forth on the nest, it is my opinion that the female sometimes becomes tired of her confinement, refuses all persuasion of the male, and will not remain on the nest until all of her eggs are cast. I noticed particu- larly in one season, that the larger fish nearly always occupied the natural nests, and it would naturally follow that there would be found the largest number of eggs. Of course this idea will not prevent an in- crease in the size of the artificial box, but even then, in my opinion, they are sometimes cramped for room.”’ There is reason to believe that this opinion is nearly correct, and it leads to the thought that whenever the size and the character of the bottom of a pond will permit it, natural nests will be productive of more eggs and fish than the same ponds with only artificial nests. The bass-culturist quoted above, an ardent believer in natural nests, said further: ‘*Where ponds are small in area, it is perhaps nec- essary that artificial nests of some character be used, 38 FISH CULTURE so as to provide more or less seclusion. From my observation and experience, I should prefer, where conditions permitted, to build no nests, but prepare for the spawning season by arranging the pond as follows: JI should construct the edges or shores of the pond in irregular shape, allowing a point to pro- ject here and there, creating small bays, somewhat like one or two of the ponds at the Drayton Plains Hatchery, Michigan. Then instead of using the arti- ficial or box-nest, I should simply provide a sunshade, set upon props or sticks, leaving all sides free and open to the unrestricted movements of the fish. In a pond of large area, I am satisfied that this is ample shelter. It is only needed to protect the fish, while hovering over the nest, from the direct rays of the sun. The size and area of the pond would furnish the same seclusion that is given in a pond of smaller size by the box or Lydell nest.’’ Bass-fry and their Care—When the young small-mouthed bass issue from the eggs they are exceedingly small and almost transparent; but in from 24 to 48 hours, depending on the temperature of the water, they change to dark brown and then to black, and resemble a newly hatched tadpole. There is no such quick change of colour with the large-mouthed bass, in which the early stages of development of the SPAWNING OF BLACK BASS 39 fry proceed much more slowly than in the case of the smallmouth. During the sac stage the fry of the small- mouth huddle close among the stones in the nest, a quivering and almost solid black mass. In this period they cling so closely to the stones that it is impossible to remove them without in- juring and killing large numbers. As the fish approach the advanced-fry stage they begin slowly to rise. When the metamorphosis is completed they approach close to the surface, provided the water-temperature is right. If when they are rising the temperature falls the little fish will drop at once to the bottom. The ascent from the nest to the surface is not sud- den but gradual, and by a series of upward and downward movements, covering a period of about three days. _ 5 LY = Us (Ameiur COMMON BULLHEAD CAT-FISH CULTURE 61 fish at that time contract fungus more readily than some scaled fishes. White and Yellow Cat-fishes—The white and yellow cat-fishes, when transplanted from rivers like the Delaware and the Hudson into interior waters in the same latitude, develop a flavour excelled by very few species. The yellow one takes very kindly to being transferred from its native environment, and land-locked, while the white cat-fish accommodates itself to changes nearly as well. Hence the culture of both these species can be profitably carried on for market purposes in towns removed some distance from sea-port cities, since the prices for them in city markets are very encouraging. One man in Pennsylvania had a number of arti- ficial ponds, each covering a considerable area of ground. One or more of them had formerly been mill-dams. At a certain period of the year he drew down the water, thinned out his stock of young bull- heads by netting them out and throwing away the smallest, returning to the water only the largest and best appearing, as he said that unless such thinning took place the entire stock would be stunted and their market value depreciated. The Commonwealth of Pennsylvania has for sev- 62 FISH CULTURE eral years been engaged in the propagation of white and yellow cat-fish on a large scale. It has, however, been giving very little attention to pond-construction for this species of fish, simply using types of ponds already built. The only uniform features have been natural clay banks and clay bottoms without any gravel coverings. The most pretentious ponds as far as size and general utility are concerned are at Tor- resdale Station, in Philadelphia. One is 150 feet Square; another is 275 feet long and 90 feet wide; others are about 100 feet by 30 feet. The largest is about six feet deep in the kettle, with an average depth of a foot and a half all over the shelf. It was formerly used for propagating sun-fish and_ bass. It is excavated throughout and is fed by a small stream. The first-mentioned pond is supplied by water pumped into it from the Delaware River. White and yellow cat-fish do equally well in both ponds, and in 1908 the square pond yielded very nearly 200,000 cat-fish from about 300 brood fish of both sexes. Spawning and Care of Young.—The spawn- ing habits of the white and yellow cat-fish are interesting. Although a nest-builder, the loca- tion of the home and the habits of each are not- ably different from those of the black bass. Instead of selecting a stony or gravelly spot as a small-mouthed bass would do, or a sandy CAT-FISH CULTURE 63 place like the sun-fish, or a moss-grown bottom like the large-mouthed bass, it chooses one of the banks of the pond or a sharp depression in the bottom. Here is excavated a tunnel or cave, sometimes equal in length to the fish itself, and several times larger in circumference. The eggs, and there are many of them, are deposited thickly on the bottom of the excava- tion and fertilised, one of the parents taking a position over them with only its head projecting from the cavern. Here it remains almost mo- tionless, rarely leaving for any purpose except to drive away an intruder, or when stirred out by a stick. Left alone, it will almost imme- diately return to its household cares. The cat- fish is a solemn and forbidding-looking creature about the head, even under favourable circum- stances, but there is something almost savage in its aspect when guarding a nest. The cav- ern, the position which the fish takes, with head only projecting, and the warlike look in its eyes, together with its capacious mouth, bring to mind some fabled monster. Under favourable water-conditions in Penn- sylvania, both the white and yellow cat-fishes 64 FISH CULTURE begin spawning about the latter part of June. The period of incubation is about two weeks. As soon as the young have absorbed their sacs and are ready to swim up to the surface, they are coaxed from their cavern to the water just outside its entrance. Here they remain for a day or two, being driven back daily into the cave when the sun has gone down, or when en- emies approach. Little by little, however, they are led away, though kept closely herded, until they appear on the surface of the water like a big quivering black ball. In this manner they work slowly back and forth over the pond. As they move, the old fish swims slowly around them, driving back into the mass any which may stray. At this stage of their development the fish-culturist steps in, and with one sweep of his long-handled scoop-net gathers in the entire school and transfers them to one of his small ponds, where they can very quickly be taught to eat ground liver, and, later, pieces of bread. The fish grow quickly, and by the first of Sep- tember are an inch or more long. Profit in Pond-culture of the Cat-fish—Few fishes offer greater possibilities than some of CAT-FISH CULTURE 65 the cat-fish, notably the common bullhead and the yellow cat-fish. Their cultivation is pecul- iarly to be recommended to farmers. Almost every man engaged in agriculture possesses @ piece of low wet land with a spring-run or a small stream flowing through it. This land is perhaps not extensive enough for ponds of a sufficient size for commercial value, but it would have to be less than half an acre to be too small to be converted into two or three cat-fish ponds large enough for an unfailing supply for table use. Mature fish in confinement will readily take almost any food which may be given them. They eat living minnows, dry bread, or chopped lungs, with equal gusto, and in taking any float- ing food make a sucking noise nearly as loud, and remarkably similar to, that made by ill-bred men when eating soup or drinking coffee. Under favourable circumstances cat-fish will be ready for the market when nearly two years old, and certainly at the age of three. Their re- markable tenacity of life should make them par- ticularly valuable for the market, since there is a very large element among consumers who in- 66 FISH CULTURE sist on purchasing alive the fish they want for their table, and living fish bring a much higher price than those which are sent to the market dead. Preparation of Cat-fish Ponds.—Construct one pond which will occupy about half the land available, and three others which will occupy the other half. The large one will be used for breeding, and for the maintenance of fish more than one year old; while the smaller ponds are for the rearing of young fish up to the age of one year. The sorting may all be done into these three ponds. Two or three ponds about 300 feet long and 100 feet wide each, and ten or twelve smaller ponds, would yield many hun- dred thousand healthy fingerlings and yearlings to be sold for stocking purposes. If, however, it is designed to raise cat-fish for food and for market there must be a decided increase in the size and number of the larger ponds. It would not be advisable to increase the size of the ponds designed for keeping those less than a year old, because they could not be easily and quickly worked; but it might be desirable to increase the number in order to permit sorting into three CAT-FISH CULTURE 67 or more sizes at least three times in the first twelve months. Sorting fish into sizes several times during the year is a very important duty of the fish-culturist. This is true even when the young are not pronouncedly cannibalistic. It is a well known fact that very young fish of the same age vary considerably in size. When allowed to remain unsorted, the larger annoy the smaller, will not allow them to eat until they them- selves are gorged, and chase them around the pond between meals. As a result, the smaller fishes do not grow, at least at the same rate as the larger. When sorting is practised, the majority of the smaller, if they are in good health, rapidly overtake the larger, and there is not much difference in size when they reach the yearling stage. At that age, the smallest, or cullings, can be disposed of, leaving the others in fine shape for rearing to market age. Where the species are cannibalistic, sorting is imperative, if it is not desired to lose more than fifty per cent. of the young stock. The larger the volume of water the more rapidly the fish will grow. The quicker the growth the sooner the fish will be ready for the market. Ponds from three quarters to one acre in area each are advised, with a length much greater than their width. Very wide ponds are 68 FISH CULTURE to be avoided, because of the difficulty in han- dling the nets when fish are to be removed, un- less it is possible to draw off all the water for that purpose. The character of the sides and bottoms of the ponds for cat-fish culture is important. When ponds are built for most types of fishes the bot- toms are gravelled, and in some instances— trout-culture for example—the sides are walled with boards, stone or concrete; but ponds for cat-fish must have the banks and bottoms of clay,—at least those portions where the fish spawn. The kettle, or deep portion, if not of clay, may be of heavy mud, but not too deep. There are two reasons for this: first, the clay banks and bottoms are essential as nest-building and spawning places; second, during the winter months cat-fishes burrow to a greater or less extent. They cannot do this where the bottom is gravelly. Two feet is a sufficient depth for the shelf, although two and one-half or even three feet is more desirable. The kettle should be from five to six feet deep. Cat-fish do better where the water is not too shallow, and for this reason CAT-FISH CULTURE 69 the greater depth of the shelf is advised. The shelf, a shoal part, had better comprise the greater part of the pond, as it gives a larger spawning-surface. The kettle naturally will be located at the outlet end. Arrangements for the inflow and outflow are the same as for bass or any other warm-water fish-ponds—that is, provide an inflow pipe, and for the outflow con- crete gate-frames with splash-boards and screens. About the same amount of water is ordinarily used as for black bass, although cat- fish can get along on a smaller supply. Too little water breeds the dangerous fungus. CHAPTER V CARP CULTURE Hap it not been for over-enthusiasm carp farming would probably now be a very large and valuable industry in the United States, and the fish generally regarded with friendly eyes. In- stead, it is undoubtedly the most execrated and unjustly accused fish swimming in American waters. The introducers of the German carp have been likened to Benedict Arnold. Many men have advo- cated laws putting a bounty on the death of the fish with a view to its extermination. Pennsylvania, in order to prevent its increase, carried in its statute books for a time a law imposing a heavy fine on any person who planted carp in any of the waters of that state. There is not a fish-crime on the calendar that has not been charged against the German carp; some rightly, many more wrongly. It is accused of being 70 CARP CULTURE 71 a spawn-eater, probably with justice; also of destroy- ing water-plants, which are almost as necessary to the well being of fish-life as the water itself. This charge is undoubtedly true. Wherever there has been a decrease in game fishes it has been accounted re- sponsible. There is little if any truth in this last statement. In many instances where carp have been pronounced the offenders, the decrease has been traced to other agencies, chief among them man. The most widespread condemnation is that it is unfit to eat, as its flesh has a strong muddy flavour due to its habit of rooting in the bottom of a pond or stream. The bad reputation of the carp was gained through over enthusiasm on the part of its friends, and misapprehension regarding the re- quirements of its successful pond-culture, when first introduced into the United States. As a matter of fact, while the carp is undoubtedly very inferior in table qualities to many native food-fishes, it is not an unpalatable fish when reared in a suitable environment. It cannot be so, since it is found on the bills of fare, at one dollar a portion, of high-class restaurants in New York and elsewhere. Without doubt, many persons who have condemned the carp most severely, have eaten it under the impres- (2 FISH CULTURE sion that they were being served with something else. Mr. John W. Titcomb, formerly the head of the Division of Fish Hatching of the United States Bureau of Fisheries, relates that in Jan- uary, 1902, 224 members and guests of the North American Fish and Game Protective Associa- tion were served with carp at a banquet, ate it and pronounced it ‘‘good,’’ under the impres- sion that it was baked red snapper. Bad Reputation Due to Improper Culture.— When the carp was first introduced into Amer- ica the authorities very properly stated that it was a highly esteemed fish in Germany andother parts of Europe; that it was very prolific, easily eared for, suitable for warm sluggish waters, and specially adapted to pond culture. There was an instant and widespread demand for the new importation. Farmers who had duck- ponds, built perhaps three quarters of a century before and never cleaned, stocked them with carp. Others built for their reception dams across streams on their bog-lands, without tak- ing the trouble to clear away the mud. Almost any muck-hole containing a few hundred gallons of water was considered fit to be utilised. CARP CULTURE 73 The craze, for such only can it be called, spread rapidly without any pretence of method or intelligence until ‘‘almost every farmer had a carp pond in his front yard, back yard, barn yard, or somewhere.’’ The crash came when the fish were large enough to be killed. As might be expected they were inedible. Their flesh fairly reeked with a smell and a taste of filth. The disgusted farmers tore down their dams and liberated the fish with blackened char- acters into the public waters. Unquestionably the carp is inferior to almost every other fish native to waters like those of Pennsylvania, but it is equally certain that if, when it was first introduced into this country, fish-culture had been advanced as far as it is to-day, carp-farming would probably be a recog- nised industry, yielding in the aggregate a huge sum of money annually. As it is, a revulsion of sentiment is slowly but surely taking place in favour of this importation as a food-fish. : Market Value.—The carp undisputably holds an important place in the market. It is worth several hundred thousand dollars a year to the state of Ilinois. Over 40,000 pounds, two- 74 FISH CULTURE thirds of which come from other states, are sold weekly in the markets of Philadelphia, while 5,000,000 pounds are disposed of yearly in New York. A five-pound live carp will sometimes bring more in Philadelphia or New York than a Delaware River roe-shad of the same weight. Almost the entire industry in America to-day depends on the carp caught from the rivers and lakes, although a large proportion are held in temporary ponds and pens before being sent to market. There is reason to believe that if states now condemning this fish would recognise its market value, would give encouragement to its citizens and would instruct them in the proper methods of culture, capital would speedily be invested and carp-farming become a profitable industry, as it is to-day in Germany. It should become profitable, because the demand for carp in the large cities is generally greater than the supply, and because in the smaller cities a demand catl likely be made for the fish. As carp-farming is not generally carried on in this country, it is impossible to say how large a tract would be necessary to insure very profitable returns, but CARP CULTURE (bs) probably any reasonable amount would yield fully as much, acre for acre, as land devoted to vegetable produce. This is important, since a carp-farm can be established on land which or- dinarily yields little or nothing. Ponds.—Hatching-houses and expensive ap- paratus are unnecessary. The entire business may be conducted by pond-culture. Mr. Leon J. Cole, who prepared a bulletin for the United States Bureau of Fisheries in 1905, entitled ‘‘German Carp in the United States,’’ says: ‘*A well appointed carp-cultural establishment has at least three kinds of ponds, each adapted for a par- ticular phase of industry. **1. Spawning ponds.—Shallow ponds in which the water is easily warmed by the sun and suitable for the spawning fish. ‘*2. Raising ponds.—Ponds usually of medium size, to which the fry are transferred and where they are retained, isolated from the larger fish, until they are a year or two old. **3. Stock ponds.—Large ponds in which the fish are kept until they have reached a marketable size; this is usually considered to be when they have reached a weight of two and three-quarters pounds to two and a half pounds,’’ 76 FISH CULTURE To these Mr. Cole adds a fourth type, namely winter ponds, located in sheltered spots, which should have a depth of six to eight feet. Winter ponds are only necessary where the stock or raising ponds are not suitable for carrying fish from autumn to spring, that is to say, where the water would freeze to or nearly to the bottom. Generally, it is not wise to build any ponds for the cultivation of carp by damming a stream unless there is no possibility of a freshet. Should it be found cheaper, and otherwise good policy, to build in this manner, an artificial ditch should be built the whole length of the pond, at one side, to carry off surplus water. If a dam built across a pond were to break out, or an overflow to occur of any considerable depth, an almost total loss of fish would result. This is peculiarly the case with carp, for that fish more than most follows currents and changes in depths. If surrounding land be- comes submerged, for instance, nearly every carp will swim from the pond to the submerged lands. The third type, described by Mr. Cole as the CARP CULTURE 77 ‘‘stock-pond,’’ should be as large in area as possible; it may properly be two or more acres in extent. Conditions which call for restricted areas for other species of fish do not obtain with carp, on account of its proneness to follow currents, so that there need be hardly any restriction placed upon the size. It is only important that, apart from the wintering quarters or kettle, there should be at the lower end splash-boards or gates which can be opened easily to permit the water to be drawn off rap- idly along a race or ditch into a pool known as a ‘‘fish-pit,’? into which the carp will go and where they can be netted out. If desired, and this is recommended by Mr. Cole, the fish-pit can be in the pond itself at the place of outlet. Ditches from various parts of the pond lead into other ditches which are deeper, and these finally lead into the fish-pit itself whence they can be taken out with dip- nets. Care of Carp.—There ought to be at least two. stock-ponds so that one can be annually drained, cleansed of sediment, and purified by the action of air and weather. To insure the best results 18 FISH CULTURE there should be a large number of spawning- ponds of small size, each large enough to hold not more than five fish, three females and two males. They must also be very shallow so that the water may be warmed rapidly by the sun. Such ponds need not be more than 20 feet long, and eight or ten feet wide. Raising-ponds for advanced fry, fingerlings and yearlings, must of necessity be much larger, and somewhat deeper than spawning-ponds. They should not, however, be of so great an area that they can not be easily seined, and the fish handled quickly and thoroughly ; but they must be large enough to carry safely a number for at least one year, preferably two. To facilitate growth, the water should be moderately warm, mostly shallow, and the ponds supplied with an abundance of aquatic vegeta- tion. A large volume of water is not essential, but enough to insure proper aeration and to pre- vent too high a temperature is necessary. Con- trary to widespread belief there can be an ex- cessive water-temperature, even for carp. Rudolph Hessel, in his work ‘‘The Carp and Its Culture in Rivers and Lakes and Its Intro- CARP CULTURE 79 duction into America,’’ says that the inflow of water into the pond should never be allowed to be direct; as, for instance, a brook falling into it. ‘‘This often causes the water to rise at an inopportune time, carrying into the pond other fishes, especially the rapacious pike. The carp also has the disposition to swim towards the in- flowing water, by which means it is drawn away from its proper feeding place.’’ If this is cor- rect, and from the investigation of Mr. Cole it appears to be, then the inflow should be so ar- ranged as not unduly to attract the fish to the spot. Kinds of Carp—tThere are three well defined species of introduced carp more or less common in American waters; namely the leather, mirror, and scale carp. The leather carp is dis- tinguished by its having no scales, or only a few on its back, but, instead, a thick soft skin, velvety to the touch. The mirror has three or four rows of very large scales on its sides, the rows being separated by a scaleless skin. The scale carp is completely covered with scales, and is neither more nor less than a developed form of the original species. All three are rapid 80 FISH CULTURE growers, attaining heavy weights and having the reputation of great longevity. Specimens weighing from 20 to 25 pounds are not uncom- mon, and occasionally there are found some, particularly of the mirror carp, which will turn the scales at 40 pounds. In water of ordinary temperature carp will acquire a weight of from three to three and a half pounds when three years. old, and where the water is warmer they sometimes reach it in a year or two. Spawning Habits—In the warmer parts of the United States carp begin spawning as early as April, but in the Middle States not until May and June. Under ordinary circumstances they require three years to reach maturity; but it is said that under very favourable circum- stances they sometimes spawn when only two years old. According to Robert A. Poppe, carp have been known to spawn when nine months old. Whatever the age, fish first spawning are from three to four pounds in weight, with a length of from 15 to 18 inches. The eggs are very small, but the number to each female is exceedingly large, a female weighing from four to five pounds yielding from 40,000 to 50,000 CARP CULTURE 81 eggs.