An Evaluation of the Roving Creel Survey with Nonuniform Probability Sampling

Abstract

A roving creel survey with nonuniform probability sampling was conducted on West Point Reservoir, Georgia, for 24 months. The sampling design is described in detail. The assumption that catch per unit effort (CPE) for incompleted fishing trips is an unbiased estimator of CPE for completed trips is tested and verified. Coefficients of variation for monthly estimates of catch and effort are used to measure the precision of the sampling design. Precision was relatively high during the summer (April-October), but decreased markedly during the winter (November-March). This change is largely independent of sample size within the range of 5-10 sample days per month leading to the conclusion that sampling effort could be reduced 50% without impairing the precision of the survey. The method appears capable of detecting changes in the quality of fishing small enough for management purposes. The paper is intended to provide guidelines for the implementation, evaluation, and modification of statistically based creel survey programs.