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Abstract
An inexpensive system to feed-train fingerling (13.1 ± 1.2 g) walleyes Stizostedion vitreum in cages suspended in ponds by using automatic feeders is described. Walleyes were initially overwintered unconfined in three 0.04-ha ponds at a density of 74,000 fish/ ha. When water temperatures reached 10°C, fish were stocked into four cages (3.5 m3) suspended in separate 0.04-ha ponds at cage densities of 938 fish/m3. An automatic feeder was suspended over each cage and dispensed 38 g of feed per feeding at 10-min intervals during daylight hours (0600–1800 hours). After 47 d, 45% of the initial population was healthy and actively feeding. Feed-trained fingerlings (19.9 g) were then stocked into six 0.04-ha ponds at 18,525 fish/ha and fed a 40% protein diet once daily to satiation. After 184 d, the fingerlings in live replicate ponds averaged (±SE) 97.3 ± 9.9 g, individual weight; 67,3 ± 7,0% survival; 491.5 ± 52.3% average individual gain: 0.86 ± 0.6% body weight/d, specific growth rate; and 840.2 ± 52.1 kg/ha, total production.