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2007-03-24 22:44:42 · 3 answers · asked by Anonymous in Science & Mathematics Zoology

3 answers

Larvae eat continuously and, in nature, their diet is principally zooplankton (mainly minute crustaceans), very small worms, and the larval stages of other aquatic invertebrates.

On completion of their larval life, freshwater prawns metamorphose into postlarvae (PL). From this point onwards they resemble miniature adult prawns and become mainly crawling rather than free-swimming animals. When they do swim it is usually in a normal (dorsal side uppermost) way and in a forward direction. Rapid evasive movement is also achieved by contracting the abdominal muscles and rapid movement of the tail fan. Postlarvae exhibit good tolerance to a wide range of salinities, which is a characteristic of freshwater prawns.

Postlarvae begin to migrate upstream into freshwater conditions within one or two weeks after metamorphosis and are soon able to swim against rapidly flowing currents and to crawl over the stones at the shallow edges of rivers and in rapids. They can climb vertical surfaces and cross land, provided there is abundant moisture available. In addition to using the foods available to them as larvae, they now utilize larger pieces of organic material, both of animal and vegetable origin. Postlarval freshwater prawns are omnivorous and, as they grow, their natural diet eventually includes aquatic insects and their larvae, algae, nuts, grain, seeds, fruits, small molluscs and crustaceans, fish flesh and the offal of fish and other animals. They can also be cannibalistic.

2007-03-26 04:08:12 · answer #1 · answered by onyx27 3 · 0 0

prawn food

2007-03-24 22:52:59 · answer #2 · answered by Deo 2 · 0 0

Stuff

2007-03-29 05:28:35 · answer #3 · answered by twilightluver 3 · 0 0

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