Wing wear affects wing use and choice of floral density in foraging bumble bees

Abstract

Damage to structures that enable mobility can potentially influence foraging behavior. Bumble bees vary in extent of individual wing wear, a trait predicted to affect mechanical performance during foraging. This study asks 1) do bumble bees distribute themselves across different floral densities in accordance with their concurrent wing wear? and 2) does wing use in foraging bumble bees depend on concurrent wing wear? We observed individually identifiable bumble bees foraging in 1-m-super-2 patches of high and low floral density of 3 plant types (Geranium viscosissimum, Melilotus alba/officinalis, and Monarda fistulosa). Bee preference for flower density was determined by an interaction between wing area and bee body size: small worn-winged bees selected patches of higher density, whereas large worn-winged bees selected patches of lower density. Bees with more worn wings spent less time in flight and flew less often; however, only foragers collecting pollen appeared to reduce wing-use behavior (i.e., wing collision frequency) that leads to loss of wing area. This study demonstrates that individuals respond to wing damage in different ways depending on their body size and foraging task. Wing wear clearly influences foraging behavior of worker bumble bee. Copyright 2011, Oxford University Press.