Predation by polyphagous carabid beetles on eggs of a pest slug: Potential implications of climate change

Harpalus rufipes and Poecilus cupreus are two widespread polyphagous carabids which are known to destroy eggs of the pest slug Deroceras reticulatum in the laboratory. To examine the effect of temperature on the predation of the eggs of D.reticulatum by H.rufipes and P.cupreus, a laboratory experiment with different temperatures and a semi-field experiment including simulated warming were performed. In both experiments, H.rufipes killed more eggs than P.cupreus, and the predatory activity of the former increased significantly with increasing temperature. To our knowledge, this is the first study on predatory activity of polyphagous carabids on the eggs of a pest slug performed under a climate warming scenario. Results suggest that biological pest control performed by polyphagous carabids such as H.rufipes upon pest slugs may be enhanced under predicted climate warming conditions.