A Statistical Analysis of Ration and Growth Relationship of Plaice (Pleuronectes platessa)

Abstract

Dawesl(1930, J. Marine Biol. Assoc. 17: 103 and 877) gave extensive data on average daily rations and fortnightly growth increments of P. platessa fed on Mytilus edulis. The data are analyzed here in an attempt to formulate a ration and growth increment relationship. Fortnightly growth increments, Aw, were arranged in 8 groups according to 8 ranges of fish weights. The growth increments in each group, associated with each average daily ration level (R), gave evidence to the normal distribution. Each range of fish weights was characterized by a certain range of daily rations associated with growth increments having homogeneous variance, as well as by a certain daily ration, Rm, associated with maximum growth efficiency. There was evidence that growth increments, of each range of fish weights, were linearly related with [image] such that the value of the square root is positive if R > Rm and negative if R < Rm, i.e., [DELTA]w = a [plus or minus] b [image] where a and b are parameters.