A Consideration on the Density Index of Fish Population

Abstract

For estimating the density of fish population, catch per unit of effort is commonly used. But in order to allow such a method, distribution pattern of fish should be researched.
In a fishing ground, distribution of individuals and schools would be not random but contagious distribution. Frequency distribution of catch of many species is represented well by P_ÓLYA-E_GGENBERGER type. And by transformation
x'=k^-1/2sinh^-1(kx)^1/2
where k is constant, the standard deviation approaches a constant without regard to the mean. By this method, we can compare the groups with each other or examine the correlation of them.
In this examination, catch of th ?? demarsal fish in the East China and the Yellow Seas was used.