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Like semi-intensive shrimp culture, intensive
marine shrimp culture is a recent development which has taken place over
the last 25 years. Like ultra-intensive shrimp culture, intensive
culture is only practiced where seed to stock the ponds are available
when needed, in adequate amounts, and of the preferred species. For the
most part, this means use of hatchery
produced PL which have been nursed 20 to 60 days (Fast,
1992).
Intensive shrimp farming introduces small enclosures (0.1 to 1.5 hectares), high stocking densities (more than 200,000 postlarvae per hectare), around-the-clock management, heavy feeding, waste removal and aeration. Aeration- the addition of air, or oxygen, to the water-permits much higher stocking and feeding levels. The water exchange rate is 30% per day and up. Frequently conducted in small ponds, intensive farming is also practiced in racoways and tanks, which may be covered or indoors. Construction costs range from $25,000 to $250,000 per hectare. Sophisticated harvesting techniques and easy pond clean-up after harvest permit year-round production in tropical climates. Yields of 5,000 to 20,000 kilograms (head-on) per hectare per year are common. Production costs range from $4.00 to $8.00 per kilogram of live shrimp. It's relatively easy to convert intensive farms to other species. Intensive farms frequently cause environmental problems. Most of the intensive shrimp farms can be found in Thailand, Indonesia and Taiwan (Rosenberry, 1998). |
