Instead of a rod mattock. Whether it is possible?
sharp change of rainy and droughty seasons is characteristic Of climate of tropical Africa. The rainy season begins in May-July and 2-3 months last, and all other part of year there is a droughty period. In process of drought approach, escaping from death, fishes come back to the rivers before channels shoal. Otherwise protopter transfer a drought African amphipneustic . Their thick body seems naked because the scales are hidden under a thick layer of slime. Pair fins lost beams and turned into the extended extremities. With approach of the dry period of fish bury in soft silt at the bottom, are turned and cover themselves with a cocoon from slime. Protopter atmospheric air through a small opening in a cocoon breathe.
“a sleeping nest“ the protopter digs the mouth. Having drained in the next portion of silt in a mouth, he with a force throws out it together with water through branchiate openings. Soft silt easily gives in to “drilling“, but to dig the subject layer of dense clay much more difficultly. Making all over the vigorous swimming movements, fish rests a snout against soil and gnaws a clay piece. The bitten-off piece is chewed, thrown out with water through the same branchiate openings. Having reached the necessary depth, fish expands the lower part of a hole (“bedroom“) exactly so to have an opportunity, having developed in half, to turn over in it the head up. Now “the sleeping nest“ is almost ready and the animal waits for full recession of water, having exposed a snout from an entrance opening. From time to time it rises to a surface for breath by atmospheric air. When the film of the drying-out water reaches the top edge of the liquid silt covering a reservoir bottom, then thanks to the respiratory movements made by fish, the part of the clay which is thrown out at an entrance opening is sucked in in it and corks an exit. After that the animal does not come to a surface any more.
In process of soil drying-out water level in an entrance chamber gradually falls therefore it turns into an air chamber, and fish, obediently following a water mirror, falls to the expanded lower part of a hole below and below, i.e. to “bedroom“ where, at last, and fades in situation, characteristic of it.
There passes day, two and on the place of a reservoir there is only a hollow covered with viscous silt and dense plants. There passes a little more time and from a reservoir there is no left no trace. It is difficult to believe that the plain which cracked with heat covered with burned vegetation was a reservoir bottom until recently and that somewhere nearby in the hardened earth hundreds and thousands of fishes sleep. Locals dig out them a shovel or a mattock at this time, finding fish behind a small conic opening on a top. It is natural that for this purpose it is necessary to know places where they lie down in hibernation. It appears, residents of Gambia can find these places aurally as, according to their statement, in a calm weather at considerable distance it is possible to hear how breathes earthed large “kambon“ (so call a protopter local population). The original way of fishing of protopter is applied by residents of Sudan. They use a special drum by means of which the sounds imitating falling of rain drops are elicited. Having given in to deception, protopter wake up and make the loud giving smacking kiss sound, giving thereby the place of the shelter, and sometimes even creep out of the nests, falling directly into hands of hunters.
Protopterov Africans collect for the sake of tasty meat. They are also useful that they eat many mollusks which are carriers of a horrible disease of the person and cattle - to a shistosomatoz.
Protopterov with success it is possible to keep in aquariums. Usually in aquariums of Europe and America protopter are delivered in a cocoon. Such way of transportation is extremely convenient, but demands big care as from - for shake-ups the cocoon can easily tear that leads to inevitable death of fish. It is remarkable also that when the cocoon of the fish who fell into hibernation adjoins not to soil, and to any foreign matter (for example, to a glass wall of an aquarium), it inevitably leads to death. That is why in artificial conditions the lower part of a wall of an aquarium needs to be covered with a thick layer of clay.
In the afternoon they are sluggish and prefer to lie somewhere under a snag, but come to life at night. Especially active they become when in an aquarium except them there are other representatives of a fish kingdom. If his neighbor not too big, a protopter just eats him, and he will attack large, will not cripple yet. And then all the same, if is able, will try to eat or kill. In fights this fish very often loses fins, however, they quickly grow up again.
Despite not friendliness, protopter very easily give in to training. If when giving a forage to knock on an aquarium wall, then in 2 - 3 weeks fish will already swim up on knock.
Protoptera - object of serious scientific researches. So, these fishes drew to themselves attention of the scientists who are engaged in creation of somnolent preparations. The British and Swedish biochemists tried to emit somnolent substances from an organism of the animals falling into hibernation including a protopter. When extract from a brain of the fallen asleep fishes was entered into blood system of laboratory rats, temperature of their body began to fall quickly, and they fell asleep so quickly as if they fainted. The dream proceeded 18 hours. When rats woke up, any signs that they were in an artificial dream, it was not succeeded to find in them. The extract received from a brain of the awake protopter did not cause any consequences in rats.
There pass time and droughts succeed heavy rains. Having got to water the cocoon razmokat, and from it there is exhausted fish. On a body wrinkles, decubituses, prints of fins are noticeable. After a long dream in water through a gill many products of an exchange are allocated, long weeks and months the protopter lived, breathed, got energy from own stocks.