The most important commercial species

Lesson 11

1. Read the words.

the tsar's court

merchants

immature

euryhaline

solar radiation

Golden Horde

Mediterranean Sea

2. Master the words.

Cossack – казак

seal - тюлень

anadromous - анадромный

estuary - эстуарий, дельта; устье реки

semi-anadromous fish - полупроходная рыба

euryhaline эвригалинный (выносящий различную солёность)

3. Read the words and put down their Russian equivalents:

Ivan the Terrible______________________________

Peter the First_________________________________

Ekaterina the Second _________________________

the Golden Horde ______________________________

pure marine ___________________________________

freshwa­ter __________________________________

wealthy inflow ______________________________

intensive solar radiation _______________________

4. Read and translate the text:

Fishing as a trade arose during the times of Ivan the Terrible. The Volga-Caspian region was always the most important from a fishery viewpoint

In the middle of the XVI century up to 30 thousand sturgeons were harvested in the Lower Volga. From the times of Ivan the Terrible large belugas and sturgeons were supplied for the tsar's court. Under Peter the First "The Fish Bureau" (Rybnaya Kontora) was established, and under Ekaterina the Second catching for fish and seal was leased to merchants. The state treasury leased lands and waters lo private persons. Fishing industrialists and Cossack forces provided catching and processing fish until 1917.

At times of the Golden Horde, the main commercial species were sturgeon and inconnu. Only in the middle of the XIX century I he catch of ordinary fish was started (common carp, bream, catfish, zander and others) and followed by the catch of vobla. At the end of the last century it constituted up to 40% in the catches of Volga fish. At the beginning of the XX century vobla became the most important mass species of fishery and its catches reached 180 thousand tons per year (about 50% of the total catch in the Volga-Caspian region).

In 1936 in the Northern Caspian, fishing with fixed seines was organized and in 1939 it became the main catching method. Kilka fishery started to develop during those years. In 1962-1965, due to the mass by-catch of juvenile and immature sturgeons and according to recommendations of the scientists, marine fishing with nets was banned and fishing was moved to river estuaries.

Ichthyofauna of the lower Volga and Ural as well as the Caspian sea and estuaries of the southern rivers include fishes of both northern and southern (Mediterranean Sea) origin. These are pure marine (herrings, hardyheads and gobies), freshwater (pikes, many of carps, loaches, etc), anadromous (sturgeons, salmons) and semi-anadromous species (some species of carps, pikes and catfishes). Marine fishes are the most numerous - 53 species (43.5%), freshwa­ter species constitute 42 species (34.4%), anadromous - 18 specie 04.7%) and semi-anadromous -- 9 species (7.4%). Due lo early isolation from the other seas, many endemic species were formed in the Caspian Sea. The low salinity of the sea dill l2-13%n) and connection of many fishes with rivers (reproduction) conditioned their euryhaline feature.

About 40 species belong to commercial species in the Caspian Sea and lower rivers, but fishing of certain species is extremely limited and actually some 25 species make a basis of fishery.

Intensive solar radiation, wealthy inflow of biogenic elements provided high productivity of the Caspian. The sea total biomass constitutes about 2,900 thousand tones.

5. Answer the following questions:

1. What were the main commercial species at times of the Golden Horde?

2. Where did vobla originate?

3. What fish species are found in the Volga-Caspian region?

4. What fish species belong to commercial species?

5. What provided high productivity of the Caspian?

6. Write out fish species, consult a dictionary if necessary.

Судак, сазан, лещ, сом, твердоголовка, бычок, сельдь, голец, щука, лосось, стерлядь, белуга, осетр, карась, вобла.

7. Which of the following words are nouns? verbs? adjectives? adverbs? Why?

Fishing, catching, fish, seal, was, merchants, land, treasury, private, persons, industrialist, state, provide, water, leased, wealthy, numerous, include, juvenile, become.

8. Read and translate the text in written.

Sturgeons (Acipenseridae). Sturgeons include six species arid one sub-specie: beluga (Hti.to huso), ship (Acipenser nudiventris), sterlet (Ac. ruthenus), Russian sturgeon (Ac. gueldenstaedti), Per­sian sturgeon (Ac. persicus), North Caspian stellate sturgeon (Ac. stellatus) and South Caspian stellate sturgeon (Ac. st. st. naiio cyrensis).

The Caspian Sea occupies the first place in the world in sturgeon species diversity, quantity and catches. The catches mainly consist of sturgeon (73%), stellate sturgeon (20%) and beluga (7%).

8. Define the main idea of the text.

Stellate sturgeon is a rather mass species. They have a long spindle-shaped body, flattened long snout (rostrum). The body length is from 90 to 160cm, weight-up to 20 kg but more often- 10-14kg. They mature at the age of 9-11 years, the life span is up to 25-30 years. They feed everywhere along the seacoast, Their main food is crustacean and worms. The height of migration into the Volga is from the first half of May until the end of June. It is an important commercial species and second only to Russian sturgeon in catches.

Sterlet is the only freshwater fish of sturgeon family in our basin. It is not large; its length is 20-80 cm, average weight is 2-2.5 kg and age is 9 years, it spawns in May, It is spread all over the Volga, It is a rather valuable fish because of its quality as food but practically does not have commercial importance, Sterlet males are used for obtaining hybrid - bester.

9. Read the text. Write out the description of beluga.

Beluga is the largest among the Caspian fishes. In the Volga its usual size is 150-380 cm, weight - 100-600 kg, age - 12-40 years. They are predators and eat goby, kilka, herring and other fish. They mature at the age of 12-14 and spawn mainly in the Volga. Spawning grounds are far from estuary (up to 800 km). They spawn every 2-3 years. Eggs released develop into larvae in 6-8 days and gradually flow downstream to the sea reaching the weight of 3-5g in the river. Dams of hydroelectric stations deprived belugas of access to the natural spawning and at present 90% of their stocks are formed from juveniles reared at fish farms. Beluga caviar is larger then that of other sturgeons and has higher commercial value in the world market.

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