Bream

Bream body high, laterally compressed, covered with thick, stubborn scales. His head was small, the mouth small, semi-inferior, retractable into a tube. The dorsal fin is high but short anal fin is twice the length of the spinal. Caudal fin with a low-cut and a long lower lobe. Colouring bream depends on habitat conditions. Lake bream, usually darker river. Overall body color is silver. Head, back and upper sides of the blackish-gray. The belly is white. The fins are gray. Colouring young bream lighter older individuals. Males during spawning covered whitish-yellowish bumps wedding attire, their body becomes rough to the touch. Of silver bream bream is different in that it has a fin is never reddish hues, smaller scales, especially in the upper body, and therefore a large number of them along the lateral line, and a few others to both external and internal features.

Bream — schooling fish. The number of individuals in the pack increases the autumn before the winter bedding. Bream inhabit the quiet and deep parts of the rivers and lakes have steep banks, rapids below with sand-silt or mud bottom. In lakes and reservoirs bream comes to the coastal area for food and for breeding. Thickets of plants, he avoids. Almost all the time bream holds in the bottom layers of water. In warm calm weather, usually before sunrise and before sunset, he can rise to the surface. Large displacement of the pack bream and can not do for a long time to visit the same place, if they are rich in food. Just before hibernation they go to deeper places. Bream, feeding in saline areas of the seas, migrate into the lower parts of the rivers at the time of reproduction. Spawning migrations and lescham peculiar animal found in reservoirs. Here bream moved in the top, and in the estuaries of the rivers flowing into the reservoir.

Early spring bream leave the wintering and sent to the spawning grounds. In the area of spawning grounds they hold deeper water and from there under the right conditions to spawn in the coastal zone, rich in vegetation. Spawning begins when the water temperature of about 11-12 °, that Ukraine is in the middle of April, and continues until the end of May, when the water temperature reaches 22-23 °. Bream can spawn in the floodplains of rivers flooded meadow vegetation on podmyta roots of willows, reeds, rushes, and on submerged aquatic plants, particularly in the pondweed. Depth on the spawning grounds ranging 0.2-2.5 m flow on the spawning grounds or may not be very weak. True, there are cases where spawning and bream in the river, where the flow velocity is 0.5 m / s. Bream spawn more often in large groups and quite noisy. This happens mostly in the morning, in calm and warm weather.

Before spawning, manufacturers go to chosen site for a while silently float on the spawning grounds, as if trying to find a suitable place to lay eggs. Then begin to move in a circle with a diameter of up to 8 meters, often exposing the back of the water while producing storm surges. Spawning game sometimes persists for several hours. Active movement manufacturers are interrupted by long periods of rest. During spawning, large males are trying to push the small males from females. Spawned, manufacturers immediately go to the deeper parts of the pond. On artificial spawning (female) bream may spawn at different depths (over 6 kg), regardless of the weather. When cold snaps stop spawning bream on natural spawning grounds, and in the deep artificial spawning Spawning can continue. Most reservoirs Ukraine puberty in male bream occurs at the age of three or four years, and for females — four or five. Dimensions of adult producers in different reservoirs vary and depend on fish habitat. For example, in the lower reaches of the Dnieper to its regulation of the smallest mature males is 21 and females — 27 cm after construction Kakhovka Reservoir on this section of the Dnieper the smallest length of the male was already 23, and females — 26 cm in the lower Danube males bream first mature at a length of 13 cm, females — 15 cm These variations in the length of the smallest producers of adult bream due to differences in the degree of development of the food supply in these waters, and this is associated with the growth rate of fish. In bream spawning females are larger than males, on average, the number of males and females almost equally, or more male dominated. Fertility is higher in larger females. For example, in the lower reaches of the Southern Bug in females 27-29 cm long discovered about 55 thousand eggs, and 47-49 cm — 675 thousand. Spawn in spawning bream eggs attached to the spawning substrate — the stems and roots of aquatic plants. The eggs are glued as long as one does not vyklyunutsya larvae. The rate of development of embryos in the eggs depends on water temperature. Thus, in the Danube bream water temperature 11,7 — 13,3 ° embryo develops for nine days, and at 15,8-17.5 °-only five. If the water temperature during the development of embryos is reduced below 9 ° C or rises above 22 °, the newly hatched larvae of many different visible deformities. In addition to temperature, the development of embryos affects the amount of dissolved oxygen in the water. Since the mass spawning bream occurs when the water temperature 18-20 °, when the solubility of oxygen is relatively low, it has adapted to lay eggs in a large area where there is vegetation and shallow depth. In such places, as a rule, does not feel the lack of oxygen. Length of larvae hatched from eggs bream does not exceed 5 mm. Most of them have a large yolk sac, head slightly tilted downwards — to the yolk sac, the mouth and lower still underdeveloped fins underdeveloped. During this period, the larva is unable to swim and hunt for food. It either falls to the bottom, or convulsive movements emerges to the surface of the water, from which descends. If the path of the larvae found an object (leaves, stalks), they are attached to it by means of devoting special glands below the eyes. Suspension larvae at rest, without movement are long enough. If they are disturbed, they "break away" from the substrate and then attached to other objects encountered in their way. About a month full of bream larvae turn into fry length reaches about 13 mm. At six weeks of age the mean bream fry is about 22 mm. At the age of one year, they can reach a length of almost 9 cm bream grow differently in different reservoirs. Almost all the males grow slower than females. The most rapidly growing both sexes in the first three years of life, and with the onset of puberty their annual growth down. For example, bream downstream of the Southern Bug at one year of age had an average length of 7.5, desyatigodovalom — 48 cm in the reservoirs of the Dnieper they grow somewhat better than in the river to its regulation.

Bream fry, for example in the river and its reservoirs, feeds mainly on crustaceans and less mosquito larvae, algae and higher plants in its diet plays a minor role. Basis of the diet of adult bream bloodworm, secondary have worms, mollusks, crustaceans and plant remains. In reservoirs compared to the river increased feeding area for bream, affecting, in particular, on its development. Bream during the movement to the spawning grounds continue to eat, if there are suitable conditions. A plump fatty fish feed less intensively. In the coastal zone bream fed intensively than in the deeper areas.

Bream — a fairly common fish. He dwells in the whole of Europe from the Pyrenees to the east and north of the Alps. The northern boundary of the CIS in the Pechora basin. In Western Siberia (the universe only in some lakes), and further to the east it is missing. Distributed in the Caspian and Aral seas. In Ukraine, the bream lives in all the major rivers, reservoirs, large ponds and floodplain lakes. It is not available in small and fast mountain rivers and in shallow lakes.

Bream bred in fish-farms vyrastnyh under the reservoirs, where it does not have a favorable breeding conditions. Is grown quite firmly established juveniles, and then released into the water. Bream should instill in those lakes and reservoirs, which are rich in benthic feeding organisms, including reservoirs of the Dnieper.

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