Estimating Population Parameters of Pterostichus cupreus and P. melanarius (Carabidae) in Arable Fields by Means of Capture-Recapture

Abstract

Capture-recapture studies on Pterostichus cupreus (L.), P. melanarius (Ill.) and Harpalus rufipes (DeG.) were carried out in winter wheat fields. These studies followed the method proposed by Jolly. Pitfall traps were used for sampling. Recapture rate for H. rufipes was too low for estimating population parameters. Sampling intensity was measured, and a test for temporary marking effects was performed. Tables for a capture-recapture analysis of population parameters are presented. Reasons for the high standard errors and differences between the species are discussed as well as the reliability of the results and possible bias that could be involved. P. cupreus was more mobile than P. melanarius, causing higher S.E. Females often seemed more mobile and showed lower catchability than males, resulting in higher S.E. Improvements in the sampling method to reduce S.E. are proposed. Estimated mean daily survival rate was close to that observed in the field.