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1 Rainbow, brown

Rainbow, brown, and brook trout are cold water fish which require well oxygenated water below 65°F. They are cultured commercially in many northeastern states. Pennsylvania and New York are the leading producers in the region. Most trout are grown in flow-through systems; although some culturists currently reuse their water and a few use cages or net pens. Rainbow trout are marketed for stocking and as food fish. Brown and brook trout are stocked for recreational fishing; some are also sold as food fish.

  1. Atlantic salmon

Atlantic salmon is native to the eastern United States and better suited to aquiculture conditions than their Pacific coast relatives. The Atlantic salmon has become an important aquaculture species. Atlantic salmon are released as smelts in streams to enhance natural populations and cultured in cages or net pens placed in areas with substantial flushing. Smelts may be produced in freshwater hatcheries or purchased.

  1. Fathead minnows

Fathead minnows are the most important live bait produced in the region. They are usually raised in ponds. Culture ponds are typically fertilized with a vegetable material such as soybean meal or wheat sorts which stimulates the growth of algae. The reresultant plankton bloom is eaten by the fish. Some growers use a low protein commercial fish feed. Potential markets exist for fathead minnows as bioassay and research animals.

  1. Channel catfish

Channel catfish are the most important fish currently cultured in the United States. Both fingerlings and feeds are commercially available. Most channel catfish are raised in the southern United States in ponds one-half to ten acres in size. Cage and net pen culture are also practiced. In an existing pond, cage culture represents one way for those considering fish farming to try their hand at fish culture with a minimal cash investment. Catfish can survive a wide range of temperatures and will tolerate brackish water.

  1. Striped bass

Striped bass and its hybrids have recently been cultured commercially. They are raised as striped bass or, more commonly, hybridized with other fish such as the white bass, white perch, or yellow bass. Hybrids usually have a deeper body, shorter tail, and more sloped head than the striped bass. Striped bass and its hybrids tolerate a wide range of temperatures and salinities, from fresh to salt water. They are a warm water species and grow best at 75-83° F. The length of the growing season is one factor that determines where they can be raised profitably. Striped bass and its hybrids are cultured commercially in ponds, flow-through systems, and cages.

    1. Goldfish

Goldfish and ornamentals are commonly cultured in small ponds or tanks. Because of their high value, recirculating systems have commercial potential. Outdoor culture units maybe covered in winter to protect fish from the cold.

7.4 Give English equivalents:

Пресноводный инкубатор, сеголетка, рыбный корм с низким содержанием белка, ручьевая форель, холодноводная рыба, тепловодная рыба, рыбные объекты.

7.5 Choose and put down the words opposite in the meaning to the given ones. Translate the combinations.

Words: brackish, recreational, cultured, salt, high, short, marine, maximal

Model: warm water and cold water fish.

    1. Fresh and ____________ water.

    2. Commercial and _________________ fishing.

    3. Freshwater and ________________fish.

    4. Low and ___________ content.

    5. Fresh and ___________ water.

    6. Minimal and ______________ cash investment.

    7. Long and _________ tail.

    8. Natural and _____________fish.

7.6 Say if these statements are correct:

  1. All kinds of fish are grown only as ornamental.

  2. Finfish, shellfish, and aquatic plants are cultured commercially for food, research, ornamental markets and so on.

  3. Rainbow trout are grown mainly in flow-through systems.

  4. Atlantic salmon are used as a bait fish.

  5. Fathead minnows are the main aquaculture species.

  6. Channel catfish can survive a wide range of temperatures.

  7. Goldfish are commonly cultured in large ponds.

7.7 Topics for discussion

  1. Speak about the aims of culturing aquatic species.

  2. Speak about peculiarities of each species cultured commercially.

Part 2

B. Potential Commercial Species

    1. 7.8 Read the following international words and translate them. (Mind the part of speech).

    2. Commercially, tropical, temperature, region, system, industry, season, incubate, details, popular, indicate, minimal, technology, principal, control, sterile.

    3. 7.9 Give Russian equivalents of the following words and word combinations.

To survive, heated units, live-bait industry, growing season, spring spawning, hatched fry, a desired size, market size, turbid water, poor consumer acceptance, value-added products.

7.10 Read and translate the following words paying attention to prefixes.

Impractical, unprofitable, reuse, reresultant, recirculating.

7.11 Read the following geographic names:

The United States, Pennsylvania, New York, Pacific Ocean, Atlantic Ocean

7.12 Read and translate the text with the help of a dictionary.

1 Tilapia

Tilapia have been cultured commercially in the United States. They are hardy, grow rapidly, and are acceptable, though not well known to consumers.Tilapia are tropical fish and require warm water to survive. If water temperatures fall below approximately 50- 55° F, they will die. In this region, most Tilapia culture has occurred in ponds during summer or in heated units such as recirculating systems.

      1. Golden shiners

Golden shiners are the mainstay of the live-bait industry in Arkansas, although some are cultured commercially in the Northeast. Usually cultured in ponds, golden shiners are less hardy than the fathead minnow. They require two growing seasons in order to reproduce. However, the golden shiner is more appealing to the angler and attains a larger size than the fathead minnow.

      1. White suckers

White suckers are captured during their spring spawning run by some bait producers. Eggs are striped and incubated; hatched fry are reared in ponds. Suckers grow faster than golden shiners and in one growing season attain a size desired by bass and pike anglers. Market size and culture details require further research.