A simple method to estimate the significance level of the catch probability in the catch removal method in riverf ish populations

Abstract

This work presents a method for estimating the signi®cance level of the capture probability when the capture removal method is used in riverine ®sh populations. The method is based on adjustment of the linear relationship between capture probability and an index of capture ef®cacy. With this method the population size, the statistic 2 and the signi®cance level of the capture probability can be estimated. This is a simple technique which can be applied in the ®eld at the time of sampling. It does not require the use of computers and can determine in situ whether the catch is valid to calculate the population density.