Fish Hatchery Management - fisheries & aquaculture

92 FISH HATCHERY MANAGEMENTFrcunn 36. Perforated aluminum screens showing (l) round holes, (2) staggeredslots, and (3) nonstaggered slots. (Courtesy California Department of Fish andGame.)actually leak if the bottom is disturbed, and it may be necessary to compacttheir bottom with a sheepsfoot roller, rather than to disk them.If a pond is to remain dry for several months it should be seeded aroundthe edges with rye grass (8-10 pounds per acte). This cover prevents erosionof pond dikes and it can be flooded in the spring to serve as a sourceof organic fertilizer. The grass should be cut and partially dried before thepond is reflooded, or its rapid decay in water may deplete dissolvedoxygen.Application of 1,000 pounds per acre of agricultural lime during the fallowingperiod, followed by disking, may imProve the buffering capacity of