A SIMULATION EXPERIMENT ON THE POTENTIAL OF HEDGEROWS AS MOVEMENT CORRIDORS FOR FOREST CARABIDS

Understanding the response of organisms to heterogeneous, mosaic-like landscapes is of key importance for landscape ecology, especially for predicting the consequences of the impacts of landscape patterns on th e spatial distribution of species. It is of current interest whether s imulation models can carry out the necessary transformation between fi eld data and larger spatial and temporal scales. We present a model wh ich simulates the small scale movements of forest carabids, adjusted t o a typical representative, Abax parallelepipedus, through hedgerows o f different widths and lengths. The modelled individual's responses to the heterogeneous landscape differ because movement patterns, surviva l times and boundary reactions differ among the different patch types. We evaluate the transition probability through hedgerows as the propo rtion of the individuals attaining a patch at the end of a hedgerow. O ur results predict maximum immigration distances of about 100 m into h edgerows for forest carabids during one season which corresponds with empirical findings based on trapping studies. This result is a promisi ng example that the effect of landscape-dependent movements can be est imated using suitable simulation models and that transformation betwee n the different scales inherent in the empirical methods, tracing and trapping is possible. (C) 1998 Elsevier Science B.V. All rights reserv ed.