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I I I I I I I I I I I I I I I I I I I . or under-feed young fry. Generally speaking, the condition of the fish and the rearing container will indicate if over- or under-feeding is occurring. Underfeeding is evident in poor growth (or starvation if{fish have not been properly trained to feed). Overfeeding results in excess feed fouling the rearing container and water quality, jeopardizingnsh health. Once pikeminnow fry have reached 2 inches in size, they are large enough to withstand sampling stress. Fish were weighed and measured monthly, and the data was used to determine the appropriate amount offeed to be fed daily. Feed charts (daily feed rations) were calculated using a modification of Haskell's equation by Buterbaugh and Willoughby (1967). A hatchery constant of 6 and a condition factor of 0.00025 was used in this equation. Monitor fish condition by using growth rates, feed conversions, and visual inspections of the fish at sampling times. Adjust the hatchery constant or condition factor from recorded data if there is a problem with the generalized values given above. These measured rations may be hand-fed six to eight times per day, or fed constantly by automated feeders. Feeding Methods An evaluation between hand feeding and the Zeigler 12-hour belt feeder (Zeigler Brothers, Gardner, Pennsylvania) was performed. Study protocol (tank size, location, water flow, fish size, etc.) was similar for hand-fed and belt-fed fish. The feeders were filled first thing each morning. The feed was distributed evenly on the belt so that it fed continuously over a 12-hour period. The fish being hand-fed were given feed six times over a six- to eight.hour period. Growth was evaluated by using feed conversions and specific growth rates. There were no significant differences in growth or survival between the two methods. There were behavioral differences in the fish's response to feeding and fright. Hand-fed fish became accustomed to feeding and the foot traffic near their tank. 'They eventually lost all fright response and became aggressive to hand feeding. These feeding frenzies would dramatically decrease oxygen levels in those tanks. Fish fed by belt feeders had a dramatic fright response to any disturbance throughout the study. These fish never became accustomed to daily routines, such as filling feeders or cleaning tanks. Oxygen levels for tanks with belt feeders did not have the dramatic ups and downs as with hand feeding. Hand feeding is recommended for fish that are to be held for captive brood stock. Fish to be introduced back into the wild should be put on belt feeders as soon as possible to help maintain fright response. HATCHERY OPERATIONS (CULTURlNG TECHNIQUES) PRODUCTION Growth Rates Like most fish, pikeminnow' growth varied greatly, depending on water temperature, culturing techniques, and feed. Under the optimum condition (700 F), and using the best-known 13