Crayfish are found in almost all rivers, and larger specimens live in water bodies with a sandy bottom. They are very tasty, and they are also used as bait for angling fish.
The following types are known:
- fat-toed;
- narrow-toed (this species has long and narrow claws);
- broad-toed (has powerful and short claws).
External structure of crayfish
The body of the arthropod is covered with a greenish-brown chitin that protects the soft parts of the animal. The body consists of a massive cephalothorax and abdomen, which is narrow in males and wide in females . The head of crayfish is elongated in cone shape and ends with a sharp awl. On it from two sides are movable eyes. As a sense of touch acts a pair of short antennae.
The organs of smell are two long whiskers. The mouth opening is located at the bottom of the head, and at the top it is surrounded by the lip and jaws, which are necessary for digesting food. River cancer has eight pairs of limbs. The front three are short jaws that help the arthropod to feed. The rest are used for movement, three pairs of them with claws, which are the most important tool. Thanks to them, the cancer defends itself or, conversely, attacks the victim.
Breeding
The period of gestation in crayfish is long. Two pairs of anterior abdominal legs are involved in reproduction. Fertilized eggs are attached to them. Beginning in the fall, the female carries her all winter and spring, and only in June-July does the offspring appear.
Molting
At this time, the chitin cover is being replaced, the gills and digestive organs are updated. Young growth changes its appearance more often than adults. Shedding occurs in the summer when the pond warms up. In the first and second year of life of arthropods, it is carried out several times. This process lasts several minutes, usually no more than 15, in the open. After changing the cover, the arthropod hides in a mink so that the shell hardens and grows stronger.
What do crayfish eat?
Soft and hard plants are also consumed. The rhizome and stem of the reed, sedge, and reed are considered a favorite treat. For a day they eat food, the mass of which is 2.5% of the total weight of the arthropod. Crayfish are happy to absorb animal food:
- water worms;
- insect larvae;
- small snails;
- tadpoles;
- small fish.
Arthropod nutrition depends on age. Larvae prefer mainly animal food, which in the diet occupies about 80%. Young growth, which has reached a length of 2 mm, adores chironomids and daphnia. When they reach two years of age, Daphnia leaves the diet. Crayfish, body length 2 cm, begin to absorb larvae. In the future, as growth increases, the use of amphipods increases. They do not swallow their prey, but bite off in small parts and slowly send them to the oral cavity.
Habitat
For comfortable living, river crayfish require certain conditions:
- fresh water reservoir;
- the oxygen concentration should be at least 5 mg per liter of water;
- pH 6.5 and higher;
- a sufficient amount of lime in the habitat (otherwise, the growth of cancers is significantly reduced);
- hard rocky bottom with low sludge content.
Where do crayfish live? River brethren prefer to dwell on the boundaries of hard and soft bottom, in coastal pits or slopes of coastlines at a depth of one and a half to three meters. The best places for permanent housing are captured by large and strong males. Females and weak males live in less adapted conditions. Young growth - in shallow water near the shore, under snags and stones. Crayfish are hermits and each of them has a shelter in which it hides from its relatives.
Arthropod hunting
Where is the best place to catch crayfish? In clean rivers with warm water, enriched with oxygen. In some reservoirs, you can catch cancer at a shallow depth (50 cm), and in others from two to three meters. In rivers with a clay bottom, they dig holes, about a meter long. And also arthropods find many shelters in places with a rocky bottom. In the first month of summer, crayfish with a strong carapace can be found on condition of a warm spring. In the case of cool or cold summers, hunting should be postponed until autumn. Where is catching crayfish useless? In shallow water, in bodies of water with a sandy or silty bottom covered with dense algae.
The best time to fish
In some regions of the country, catching crayfish is restricted or completely prohibited. They can not be hunted during the gestation period of future offspring. In some areas, the acceptable size of cancer is established, after which it is possible to catch it.
A complete ban on these actions exists in the suburbs and directly in Moscow itself. Therefore, you may not be interested in the question of where crayfish are found in the suburbs. During the fishing period, no more than three traps or rakolovki with a diameter of 80 cm and a cell pitch of about 22 mm can be used per person. Hand hunting by diving or fording is prohibited. For illegal fishing in each region there is a fine, the amount of which varies in the regions.
Places where arthropods can be found
Mastering the knowledge of crayfish is a prerequisite for a rich catch. It is believed that they live in rivers with stagnant water, as well as in swamps. However, these arthropods prefer clean, flowing ponds with a mild course.
In each of them there are sites that these animals have chosen for permanent residence:
- Coastline with stones . This is the most attractive place for crayfish, as they can live at the surface of the earth under the cobblestones. At the bottom of the pond, they build holes and hide in them during molting.
- The cliff shore . In cases where the depth in the river varies, and under the coastline can reach two meters, crayfish settle in these places. A prerequisite is the presence of peat or silt on the bottom surface in a reservoir.
- Plant with snags - these are places where crayfish are found in large numbers. It is there that you can meet quite large specimens.
- Sand bottom of a reservoir . In these places, hunting for crayfish is very simple. A little algae, the bottom is transparent and clearly visible. A successful hunt awaits everyone in these reservoirs.
- Shell rock . The bottom strewn with them and the presence of sites with reeds indicate the presence of crayfish in these places.
- Holes and holes in the ground . In places with steep banks, small holes with a diameter of about five centimeters can be observed. They live crayfish.
- Cans in the water . The presence of beer bottles and other containers in the water are places where crayfish are found, they are hiding in them. When fishing, you should check each of them.
Good catch conditions
- Well ventilated and lit pond. In a muddy and dark environment, crayfish will move very quickly and will be difficult to catch. When hunting in such conditions, special traps are set at noon, which are checked in the morning.
- A specific time of day. How to catch crayfish in the summer? In the daytime, arthropods hide and are not active. During this period, you can find those individuals that are not very well hidden, and catch them with your hands. After sunset, crayfish begin to peak activity. This time is considered ideal for setting traps. Some people prefer to hunt them at night, using lights to search for them. When hunting in the warm season, a rich catch awaits you. In late autumn and winter, crayfish live in their burrows and do not leave them until the onset of hot days.
Arthropod hunting
How to catch crayfish in the summer or in another period? First you need to find the pond in which they live.
- Most beaches have places where reeds grow, there, as a rule, people do not swim and do not scare crayfish. Take the time to swim along the reeds and carefully inspect the bottom, as they are perfectly hidden in the reeds.
- Catching crayfish in quiet places with tree roots and snags is a pleasure, the main thing is to know the bottom. They are hunted, they must be resolutely not doing any sudden movements. In such places, as a rule, large individuals live. They are quite slow and are not difficult for experienced catchers.
- In rivers with a rocky bottom, there are many natural burrows for crayfish, in which they often hide from danger. It’s better to grab their mustache than claws. Do not put your hands in burrows; there is a chance of injuring them. There are cases when large stones pressed down the upper limbs to catchers.
- In reservoirs, where the bottom is strewn with the remains of reeds, as well as river mollusks, crayfish are frequent guests. You must swim carefully, inspecting the bottom. Be careful, as you can easily injure yourself on mollusk shells.
- The most successful place for both beginners and professionals is the sandy river bottom.
- Crayfish should be caught in the hole very carefully. If you find a place where near the shore a depth of two - three meters, then under the water you can see several moves. Live crayfish in such burrows are very rare; these burrows belong to musk rats. The crayfish houses are small, up to five centimeters high and eight wide, depending on the size of the arthropod.
- Favorite place is broken bottles, in which there is a whole bottom. In most cans, bottles are crayfish. There are a lot of such containers in almost any body of water.
If you are not interested in an independent cancer hunt, then you can buy it. When choosing, pay attention to the tail. Live cancer he is pressed tightly against the body.