Functional and Behavioral Responses of the Natural Enemy to , at Different Temperatures.

Unlabelled: is the dominant predator of pear sucker () in the UK. migrates into orchards in spring or is introduced as a biocontrol agent, reaching peak population levels in July-August, contributing to effective control of summer pear sucker populations. However, due to temperature dependent development and metabolism there are concerns that populations or feeding rates may increase due to changing climatic conditions. Thus, how responds to temperature, impacts its ability as a biocontrol agent. Functional response assays, monitoring attack rate and handling time of and behavioral assays, using Ethovision tracking software occurred, to assess the impact of temperature on predation. Experiments were conducted at current and future July-August mean temperatures, predicted using RCP4.5 and RCP8.5 (medium and high, representative concentration pathway) emissions scenarios, using 2018 UK Climate Projections (UKCP18). All treatments demonstrated a Type II functional response, with female anthocorids demonstrating shorter handling times and higher attack rates than males. Males showed longer prey handling times at 18 °C compared to 23 °C and more time was spent active at lower temperatures for both sexes. Females did not show significant differences in attack rate or handling time in response to temperature. Overall prey consumption was also not significantly affected by temperature for either sex. This study suggests that anthocorids are likely to remain effective natural enemies under future predicted temperatures, due to non-significant differences in prey consumption.

Supplementary Information: The online version contains supplementary material available at 10.1007/s10905-023-09836-5.