Английский язык: Сборник текстов и упражнений. Дьякова Н.П. - 64 стр.

    11. Тиляпии – вторая группа широко культивируемых рыб в мире, но
они очень чувствительны к изменению температуры воды.
    12. Тиляпии – теплолюбивый вид (warm water), они умирают, когда
температура воды опускается ниже 50°F (10°C).
    13. В настоящее время тиляпии разводят в тропиках.
    14. Известно, что они быстро растут, легко и быстро размножаются,
выносливы к плохому качеству воды, в течение нескольких месяцев дости-
гают размеров, пригодных для продажи.
    15. Тиляпии питаются как растительными, так и животными организ-
мами, и им не требуется дорогой готовый корм, если природные запасы пи-
тания истощаются.



                         Text 23
     LEADING AQUACULTURE SPECIES IN THE UNITED STATES

    Finfish aquaculture in the United States is dominated by channel catfish cul-
ture in the south and trout production (primarily rainbow trout) in the north. Aq-
uaculturists are also raising salmon in marine net-pens and a few other fishes
like red drum, grass carp and sturgeon are also being cultured. Marine inverte-
brate culture involves the production of oysters, mussels, clams, shrimp and
crayfish.
    Channel catfish culture is centered in Missisippi, where ideal conditions exist
for the construction of ponds and where large volumes of ground water are avail-
able. Since the early 1960s, when commercial catfish culture began to develop in
the United States, an meal pond production has gone from an average of about
1000 pounds per acre (kg/ha) to in excess of 4 000 pounds per acre (kg/ha) on
well-managed farms. Good quality control has produced a widely accepted prod-
uct that has been finding increasing favor among the consuming public outside of
the south, where catfish has been a traditional favorite. Catfish farming is also
practiced in various other states, though the farther north one goes, the shorter the
growing season and consequently, there are few catfish producers in the north.
Besides Mississippi, some of the key catfish producing states are Arkansas, Loui-
siana and California. The catfish industry is presently valued at over $ 400 million
annually.
    Over 90% of the trout produced for human consumption in the United States
are grown in the immediate vicinity of Twin Falls, Idoho. The water from under
ground rivers in this area is of excellent quality and nearly ideal temperature for
trout production. The trout industry is somewhat smaller than the catfish indus-
try at the present time and does not appear to be growing appreciably, though
there is significant potential for growth if new markets for the product can be
developed.
    Atlantic and coho salmon have been produced in net-pens in Puget Sound,
Washington for a number of years, and a complementary Atlantic salmon industry
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