Fish Hatchery Management - fisheries & aquaculture

2Hatch"ryOperationsProduction MethodsThe information presented in this chapter will enable the fish culturist toemploy efficient management practices in operating a fish hatchery. Properfeeding practices, growth projections, and inventory procedures are a fewof the essential practices for successful management. Although particularspecies are used in examples, the concepts and procedures presented in thischapter can be applied to warmwater, coolwater, and coldwater fish culture.L ength- Weight Re la tions hipsIncrease in fish length provides an easily measured index of growth.Length data are needed for several aspects of hatchery work; for example,production commitments are often specified by length. On the other hand,much hatchery work, such as feed projections, is based on fish weight andits changes. It is very useful to be able to convert back and forth betweenlength and weight without having to make measurements each time. Forthis purpose, standardized length-weight conversion tables have been availablefor several years. These are based on the condition factor, which is theratio of fish weight to the length cubed. A well-fed fish will have a higher60