Part 3

If you are going into Frog Raising as a business, we recommend that you make a small beginning, for nothing is more discouraging, after having gone into a business exclusively, than to have reverses in the start and lose a large portion of your investment for want of a little practical experience. Many persons have met failure by starting on a large scale at first, and without practical experience, where had they started small might to-day be a grand success. This caution applies in all business ventures, and it's the mistake that is made and cause of most failures.

When to Begin.

We recommend the active work to begin in the early spring. Get your ponds ready as soon as possible. Get your stock and place it early, so it becomes familiar with its new quarters before the breeding season sets in.

How Much to Invest.

This, of course, depends largely on the circumstances. If you have abundant means and delight in some hobby and want to make a fancy proposition out of it, why you can make your ponds as expensive and picturesque as you wish. But for those who wish to make a business for the benefit of the income to be derived, should start with a small pond and about six pairs of Frogs. Then gradually increase your breeding pond as your stock and ability to handle it demands. Don't start with Frogs under four years of age. They will be the cheapest in the end.

The Ponds and How to Construct Them.

If you have a running stream of water on your place, the work of building the ponds is much easier than where you have to depend on filling them from pumped water.

It is necessary to have several ponds, one large pond is not satisfactory. The reason for this is explained later. A plant for business should have at least four ponds. The depth of the ponds need not be very great, three feet is ample, and they could be less if you can have a good loam bottom that will hold water. But three feet is very satisfactory, and this graduating off to two feet, and one foot deep at the bank is plenty. A good shape and cheap way to build the ponds is like the cut shown. If the ground you have won't allow of this arrangement why make to best arrangement your ground will permit for convenience, carrying out the plan advisable for Raising Frogs. You must have a breeding pond, a hatching pond, a raising and a stock pond, four ponds in all. The stock pond should be the largest, permitting of plenty of room for growing and opportunity to get food. The size of your ponds depends largely on the amount of land available, its topography and the water supply. Ponds not less than one-half acre in area, with the inlet at one end and the outlet at the other, in a line of its longest axis, generally produce the best results, though smaller ponds can be successfully used.

At least one-fourth of each of the ponds should not be over one foot in depth, and this portion should be planted with pond weed (Potamogeton) and water weed (Elodea, or Anacharis) to facilitate the production and growth of the minute animals which furnish so large a part of the food for the Frogs at all stages of growth. The rest of the pond should have a gradually sloping bottom, and consequent increase depth to the outlet (or drawoff), where the water should be at least five feet deep, so that in drawing off the ponds the stock can be assembled in a small area for sorting, etc. The bottom of the ponds, preferable, soft muck, in which the Frogs can bury themselves in cold weather and avoid against danger of freezing. In the middle of all the ponds, except the spawn hatching pond, water lilies should be planted, the large pods, such as (Nymphea alba). These plants furnish hiding places from fish hawks, also serve as a sun shade and stool for sunning during summer. It is not advisable to place large bowlders in the pond, as they are in the way of seining or netting, and furnish an acceptable resort for crawfish, which are enemies when large. Nursery ponds should be constructed to afford young protection from enemies and to produce the greatest quantity of insect life suited for their sustenance, and this is better accomplished with a number of small ponds than with one large one. A good working size for spawn breeding is from 40 to 50 feet long, by 12 to 15 feet wide, with a depth of from 18 to 36 inches deep to the outlet. Where the topography of the ground will permit it is better to have the nurseries immediately adjoining the spawning pond. With water supply from same source, so that there will be but slight difference between the temperature of the shallowest part of nursery pond and surface of water of spawning pond. If the location is infested with crawfish or snakes the nurseries should be protected by wire screens. The spawning nursery ponds may be combined by constructing one comparatively long pond, narrow near the middle, so that the general shape would be like an hour-glass. Across the narrow part is to be stretched a screen of one-quarter inch wire cloth, which will confine the spawners to the deeper end of the pond, while the fry or hatching spawn will be kept separate. This form of pond is advantageous where for any reason only a few ponds can be built. Between all ponds that are connected they should be screened where water runs from one pond to the other, that is, at the inlet and outlets.

Each pond should be surrounded by one-half inch wire mesh two feet high. This makes a protection to the ponds from enemies, and also keeps the Frogs confined to the ponds they are intended.

Care of Ponds.

The accumulated decayed matter ought to be occasionally removed. The frequency of this depends on character of the water supply, the amount of silt it brings into the ponds, the character of the soil, and on the thoroughness of the yearly removal of the surplus vegetation. Care should be taken that the ponds do not become offensive with stagnant water and rotten vegetation. This condition is detrimental to large production; while abundant pond vegetation is favorable to a large production of fry it must not become decayed. It is sometimes so luxuriant that it settles down in a blanket-like mass and smothers and pens in many of the young Frogs. Under such conditions it should be removed frequently. This can be done by lowering the ponds, if they are built so they can be drawn off, which is a very desirable and convenient way if the topography of the land will permit. A strong flat-bottom boat should be made, in which can be taken the surplus matted vegetation and carried off. At each end of the boat a ring should be fastened, through which stakes can be driven to hold the boat at points in the pond to be worked. The vegetation is raked from the water in small lots. Care should be taken not to bring up any of the small Frogs and Tadpoles with the vegetation. It should be removed from the banks of the ponds at once, as it will rot very fast, and its presence is objectionable.

If a boat is not used the vegetation can be drawn near the shore with long-handled rakes and taken out with long-handled pitchforks made especially.

This method is simple and much more economical. Two men can accomplish more than five men by the other method. The advantage in favor of the boat is that you do not need to disturb the whole mass, but pick it out here and there as you think best, and have it more uniform and not destroy the roots so much.

Great Profit in Swamp Lands.

Swamp lands, on a farm, converted into Froggeries, bring in large profits. If you have a piece of ground which is swampy, which can be found on most any farm, and you do not convert this into "Raising Frogs," you are losing one of the most profitable products of your farm, as more money can be made from an acre of swamp land in a Froggery than ten acres in wheat, if properly managed, and with little expense. You first want to excavate a portion of it where you can have water, 50 x 15 feet, and another part of it 15 x 20 feet, and fence it in, as explained above with a 2-foot one-half mesh wire. In the larger pond place the breeding Frogs, and in the smaller one hatch out the spawn, and when they are developed into Frogs turn them loose on the swamp to grow until they maintain marketable size. If there is a small stream or ditch running through the swamp, which very often is the case, then it is an easy task. And here is where the old saying can be applied, "Makes money for you while you sleep." And good, big money it makes, too. Don't put off turning your swamp into a money-maker. DO IT NOW.

The Edible Frog (Rana Esculenta.)

Two species of Rana are common in America and Europe, viz., Rana esculenta and Rana temporaria. The latter alone is indigenous to Great Britain, and varieties of it extend throughout temperate Europe and Asia to Japan, and one variety (pretiosa) exists in the United States. The edible Frog (Rana esculenta), however, has been introduced into England. An Indian species (Rana breviceps) and several South African species burrow in the ground.

ECOLOGY AND HABITS. The skin of Frogs is usually smooth and free from warts or horny excrescences. It is invested with a colorless epidermis, which is shed from time to time as the creature grows; this splits along the back and thighs, is worked over the head like the taking off of a shirt, and usually eaten by the wearer. The deeper layers contain much pigment, in cells which are more or less under muscular control, enabling Frogs to change their hue to conform to the background.

Frogs are carnivorous, and in the season of activity are likely to be very voracious. The terrestrial and arboreal forms feed mainly on insects, worms, etc. The aquatic kinds also catch insects, but subsist more on aquatic animals--worms, tadpoles, small fishes, and other Frogs. These are seized and slowly swallowed, often, where before the remainder, perhaps still alive, has been got within the mouth.

Extremes of cold or drought in climate must be avoided by Frogs. Moisture of the skin is necessary to their health, and in very dry places or seasons they survive only by going deeply under ground. Thus some tropical species get through the "dry season." The frogs of northern climates endure the winter by clustering about spring-holes and other places where the water is comparatively warm and free of ice; or else by hibernating in the mud. Terrestrial species bury themselves for the winter in the loam, or burrow into the dry dust of rotting logs and stumps. Their vitality is strong, and their power of regeneration from partial congelation is very great.

Though most species live always in or near water, many spend the greater part of their time away from it, and often in bushes or trees. These, however, go to the water to breed; and as this function is likely to demand attention early in the spring, it is then that these animals make themselves most conspicuous by the incessantly uttered croaking or rattling calls of the males, which are almost as varied as the songs of the birds, and more ventriloquistic. These are wholly the cries of the male Frogs, and cease when the mates have been found and have spawned; and to assist in producing them many species have gular air-sacs, which are connected with the vocal organs and furnish the power required for the loud and insistent utterances. The great ear-drums correlated with this vocal power are conspicuous in many species.

The reproductive habits of Frogs are various. All of our common species lay their eggs in water, the eggs being fertilized as they are laid. As the eggs are laid they are inclosed in a gelatinous envelope secreted by the female. This swells and protects the eggs from injury, from being fed upon, from the direct rays of the sun, and in some species it serves to float the eggs at the surface of the water, where oxygen is most abundant; finally, the envelope serves as food for the young frogs. The mouth of the tadpole is small and provided with a horny beak, which takes the place of the teeth which are not yet developed. The tadpole feeds on algae that cover stones, and on the flesh of dead animals. The long, spirally coiled intestine, which can be seen on the under side of the animal, is an adaptation to its prevailingly herbivorous diet, which requires a prolonged digestion.

The tadpole usually lives in the water for two or three months before it takes to land. In the Bullfrog, however, the transformation (see TOAD) does not take place until the second summer.

In many tropical Frogs the reproductive habits are much modified. One species (Phyllobates trinitatis) of Venezuela and Trinidad carries its tadpoles on its back, to which the young attach themselves by means of their suckers. A frog of the Seychelles Islands lives in the tree-ferns far from water, and carries its young about on its back, to which they are attached by their bellies. In the Kameruns lives a Frog that lays its eggs in a foamy mass on the leaves of a tree. When the larvae are developed the mass becomes slimy and the tadpoles swim about it, and when a heavy rain falls they are washed into pools of water lying at the bases of the trees. The foam is probably produced as it is in culinary operations, by air being entangled in it by a beating that the Frog gives the jelly with its feet. The inclosed air may well serve in respiration. Compare TOAD.

UTILITIES. Among both civilized and savage men Frogs are a culinary dainty. The edible European Frog is so much prized in France that it is bred for the market in large preserves. In the United States both the Bullfrog and spring Frog are sold in the markets. In France and the United States the hind legs alone are eaten; they are known as "saddles" to American marketmen, and are usually served at table fried. In Germany all the muscular parts are served stewed, often with sauce. Frogs have enabled man to contribute much to his knowledge of physiology. The tail of the tadpole, so frequently fed on by dragon-fly larvae and other aquatic enemies, has great capacity of regeneration. The study of its re-formation has added to our knowledge of the regeneration of animal tissue. The circulation of the blood, so readily seen by the aid of the microscope in the web of the Frog's foot, is a classic and painless classroom demonstration. Observations on the response of Frog-muscle to stimuli led the great Italian physiologist Galvani to the discovery of dynamical or current electricity, known to us as galvanic or voltaic electricity.

Nests and Nest Building.

Whenever the spawning period occurs, ample warning will be given, as the male Frogs will begin croaking for their mate, and will be seen near the shore. Early in the spring is the breeding season, and the Frogs will be seen in pairs, working in company, selecting nests, which are in place where there is a vegetation to attach the spawn, near the surface of the water, as the action of the sun has much to do with the hatching of the spawn.