Wind slows play: increasing wind speed reduces flower visiting rate in honey bees

Abstract

Wind is an understudied environmental variable capable of having profound impacts upon the foraging behaviour of flying organisms. We investigated the effects of wind and temperature on honey bees, Apis mellifera , foraging on two plant varieties, Lavandula x intermedia ‘Grosso’ and Origanum vulgare to determine how wind influences foraging behaviour and whether responses differ between the plant varieties. Fans and an artificial wind break were used to generate wind speeds from 0 to 3.5 m/s with the following behaviours examined in a minute of foraging: number of flower visits, handling time per flower, interflower flight duration and proportion of flowers walked to. Flower movement was quantified using video footage and imageJ tracking software. Bees visited significantly fewer flowers with increasing wind speed on both plant varieties, with an average decrease of 38% between the lowest and highest wind speeds. However, the reduction was significantly steeper when foraging on O. vulgare . The reduction was due to an increase in handling time on both varieties, with interflower flight duration unaffected. Temperature had no effect on flower visit rate for either plant variety. The only behaviour influenced by flower movement was handling time, which was found to increase with flower movement. However, this increase did not result in fewer flower visits. Our results support previous work on artificial flowers which determined that the direct effect of wind on the bee influences foraging efficiency and behaviour more than the indirect effect of flower movement. • The effects of wind on A. mellifera foraging on two plant varieties were tested. • A negative effect of wind on foraging rate differed between plant varieties. • Flower movement did not appear to influence flower visit rate. • Handling time increased with wind speed, causing the reduction in flower visits. • Wind is capable of significantly reducing A. mellifera foraging efficiency.