Dispersal capacity of larval green lacewings (Neuroptera: Chrysopidae): laboratory-derived estimates and simulations

Abstract Biological control programmes often involve releasing natural enemies to control pests that are mobile, patchily distributed, or both. Determining the optimal dispersion of release points for biological control agents is challenging, particularly when knowledge of prey locations is imprecise or information on agent dispersal capacity is lacking. Chrysoperla rufilabris Burmeister (Neuroptera: Chrysopidae) is a commercially available green lacewing species that is often released in the larval stage as an augmentative biological control in various agroecosystems. We characterised the dispersal capacity of C. rufilabris using approximately 5-minute laboratory assays and then used our laboratory data to simulate dispersal over increasing windows of time. Larvae crawled a median of 0.5 m per 5 minutes, corresponding to median (95% confidence interval) simulated dispersal distances (metres) of 2 (0.1–10.3), 12 (0.4–59.6), and 25 (2.2–107.1) within 1, 6, and 12 hours, respectively. Our simulations suggest that larval C. rufilabris should be physiologically capable of dispersing several metres in search of prey following their release, although field dispersal capacity and behaviour could differ markedly from our laboratory observations. These findings will help to inform the dispersion of release points and underscore the ability of larval lacewings to move long distances after shipment.