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Beluga Sturgeon fish identification, its habitats, characteristics, fishing methods.
The English name Beluga comes from the Russian (beluga) or (belukha) which derives from the word (belyy), meaning "white". This is the biggest fish, found in fresh waters, since in some circumstances, it reaches a length of several meters and weight to 1120, even 1280, and in former times more than 1600 kg. Heavily fished for the female's valuable roe known as beluga caviar - the beluga is a huge, slow-growing and late-maturing fish that can live for 118 years. Beluga is the largest sturgeon and largest European freshwater fish, also the most expensive fish.
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The Beluga or European sturgeon (Huso huso) is a species of anadromous fish in the sturgeon family (Acipenseridae) of order Acipenseriformes. It is found primarily in the Caspian, Azov and Black Sea basins, and occasionally in the Adriatic Sea.
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Description
In addition to size, beluga easily distinguished from all other sturgeons by its thick cylindrical body and a short moderate and pointed snout, turning slightly upward, which is somewhat translucent, so as not covered by bone scutes.
The mouth is huge, takes up the entire width of the head and is surrounded by a thick lip with the lower lip not continuous, interrupted at center. Barbels are oval or flat, differ in their width, leaf-like posteriorly, reaching almost to mouth. In addition, bone scutes on the head and beetles, particularly the lateral and ventral, appear to be relatively little developed. The overall body color is ash-gray or greenish, flanks are lighter and yellowish, and belly and snout are grayish-white.
Distinguish Characteristics
- Dorsal soft rays: 48–73
- Anal soft rays: 22–41
- Dorsal scutes: 9-17, common 12-13 (first one smallest)
- Lateral scutes: 41-52 on each side
- Ventral scutes: 9-12 on each side
- Max length: 8 m.
- Max weight: 3,200.0 kg
- Max age: 118 years
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Coloration of the Kaluga is dark yellowish green on dorsal side of lateral scutes, yellowish green between lateral and ventral scutes, and light grey-white on the ventral side. Dorsal sides of paired fins yellowish green and ventral sides are white. Dorsal and caudal fins are greenish and anal fin is whitish.
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Habitats
Beluga sturgeon is pelagic at the sea, following its prey. Most of his life beluga is spending in the sea and at the reaching a maturity age every year is returning to the river to spawn. Juveniles occur in shallow riverine habitats during their first summer. Young fish are over age of puberty, as well as the entire winter in shallow estuaries or small water depths and in more places as deep winters idle fish returning from the rivers in late summer and early autumn, and finally, to the greatest depths of the inhabit in the old beluga already unable to reproduce. It is quite possible even that larger specimens of this fish come from the sea only once in several years.
Caspian and Black seas with their basin fresh water rivers: Volga, Ural, Kura, Don, Kuban flowing into them, are almost the main areas of finding Beluga sturgeon and some fairly plentiful area is the Danube. After the spawning fish returned to the sea. It migrate very far, the more the beluga species, the further they migrate to spawn. Occasional beluga comes from the Black Sea to the Mediterranean and Adriatic, and was caught also near the Venice.
Beluga sturgeon feeds mostly on crustaceans, mollusks, mysids and amphipods and sea fishes like Black Sea whiting, anchovies, flatfishes, gobies, and fry of bottom-living fishes. The main food for Beluga, like for other large sturgeon are mollusks. The young fish must stay near the mouths of rivers, where the shells are smaller and have thinner shells than in the deep seas. In the sea, where the ice is often cracked and fish are rarely needs a free flow of air, the beluga was seen for feeding the food that are there all year round.
A true predatory species; it will eat invertebrates, molluscs, amphibians and crustaceans but mostly fish. Other food groups include waterfowl, seabirds and aquatic mammals. It lives by one rule: If it fits in its mouth it can eat it and they have very large mouths. They can have cannibalistic tendencies especially when young it will eat anything they can catch.
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Spawning
Males mature at 10-16 years and females at 14-20 years. Beluga that is achieving sexual maturity is entering into the sea in the spring and autumn, the autumn migrations over winter near the spawning ground and spawn the next spring. Some fish that spent winter in the rivers, are older and entering opening from the ice river just to spawn. That Beluga should sweep spawn in the spring. The fish move up the rivers through deep channels, males reaching the spawning grounds before the females and spawning tends to take place between April and June when the water temperature is between 48-63°F (9 - 17°C). They spawn in the main course of large and deep rivers with strong current of 1-2 meters per second and on rocky or gravely bottom.
Belugas is predatory fish, and in addition to shells, they are also attracted to huge shoals passing white fish like Caspian roach and Astrakhan herring, which spend all winter in the open sea. Beluga does not feed in the sea only in December and January, months where it feed in the river. They begins to feed in the sea in February, after the first ice’s hacks, exclusively on amphipods - small shrimp, scallops, and sometimes ducks spending winter in the Caspian region and newborn seals. But then, late February in early spring, the main food of Beluga consists of roach, huge shoals of which entering in the Urals and the Volga River. Followed by roach in March there are shoals of young belugas, approximately 5 ft (1.5 m) in length and 53 lbs (24kg) weight, are going to the seashore, playing on the surface, and sometimes go under the ice.
Beluga enter the river before other red fish, and this fact in connection with their extraordinary voracity explains why Beluga not like other sturgeon do not feed only when it is in a hurry to spawn mature eggs.
At the same time with young fish, the larger Beluga, which survived on the river after winter, is spawning much higher than the young sturgeons. The larger the beluga, the more it rises for spawning, perhaps because the big fish generally spawn later and it is required longer for her sexual products to ripen. Also if the fish does not find good spawning conditions, it does not lay eggs, and latter starts absorbed by the body. This is probably why the older and experienced fish enters the river long before the spawning season starts, in summer and fall.
Despite its early progress, still beluga lays eggs later than other sturgeons. It begins spawning in May and spawns a fairly long time, about a month. Like most sturgeon species the same female fish will not spawn each year, only once every several years. Females can produce 3,000-4,000 eggs per 1 lb of body weight. Beluga is often jumping during spawning season, in order to help facilitating the eggs, and to release eggs from the sacs. On the other hand, the red belly of spawning belugas and other red fish shows that this goal is achieved solely by friction on the rocks. However, it is possible that the friction on the rocky bed, which promotes the hardness and size of abdominal bugs, serves only to dig holes in the stones like some salmon. During the release of eggs male rubbing against female and squeezes out a milk.
The eggs are 3.5-4.5mm in diameter and hatch from 1 week to 10 days at 54°F (12°C). After the hatching the fry are 11-14mm long and is feeding off the egg sack for 10-14 days and are 18-20mm long before beginning to feed normally. The fry stayed for about a month in the spawning grounds before will drift down river feeding as they go, spending the summer in the warm coastal water. Most of the young fish caught in the sea at shallow depths, where the first time they feed shells, small crustaceans, but soon, probably on the 2nd year of life, begin to eat white fish, like roach. They later than other sturgeons and other red fish are falling into the sea, and sometimes even if there are enough food and deep pits in the river they stay here for the winter.
In July, at a time when larger Beluga Sturgeon begin to enter the larger river for spring rise, the Beluga just spawned eggs, went into the deepest and coldest location of the river and greedily grab food, everything that they found. These hungry belugas are having an extraordinary voracity. They are well-adapted to finding food drifting by with their excellent sense of smell and taste. A Beluga's taste buds are located on the outside of its mouth. This, along with the barbels, allows it to see the food before sucking it up into its mouth.It often digs the nose in the mud, and in general constantly kept at the bottom and only at dawn comes to the surface.
Belugas caught with seines, mostly smooth with large networks wholes; main fishing of this fish is on the high seas. Fisheries are based almost entirely on the value of the caviar, but meat also is sold fresh, smoked and frozen; eaten broiled, boiled, fried and baked.
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