ABS 2022
The Interplay of Experience and Pre-existing Bias in Nectar-Robbing Behavior by Bumblebees
Daniel R. Papaj, Minjung Baek. University of Arizona, Tucson, AZ, United States

The ontogeny of nectar robbing by pollinators is not well understood. Here, we investigated the role of pre-existing bias and experience in nectar robbing by bumblebees. Nave Bombus impatiens workers foraged individually on Tecoma stans flowers in one of two treatments. One treatment offered open flowers with an artificial slit, allowing the bee to rob or enter legitimately; the other treatment offered flowers with slits whose corollas were plugged, requiring the bee to rob. Bees were tested twice, once on each treatment, the order of treatments balanced. First attempts by nave bees were nearly always legitimate attempts regardless of treatment. Most bees in both treatments robbed during a trial, but plugged flowers were robbed significantly more. Treatment order mattered: bees induced to rob on plugged flowers continued to rob even after legitimate access was restored, suggestive of learning and memory. We speculate that the initial bias towards legitimate visits was due to floral traits to which bees respond innately. We conclude that studies of cognition are essential to understanding cooperation and conflict in the plant-pollinator mutualism.