The Role Of Experience In Nectar Robbing By Bombus Impatiens

Abstract

Bees encounter multiple flower species and may use different strategies to forage on them. For sempetalous flowers, that strategy is often nectar robbing. There has been much research done on the ecology of nectar robbing, especially from the plant’s perspective. However, the ontogeny of nectar robbing is not as well understood. In this study, I investigated the role of experience in nectar robbing behavior by Bombus impatiens workers. Individual bees were released into an arena containing six Tecoma stans flowers in one of two treatments. The first treatment consisted of normal open flowers, allowing the bee to rob or enter legitimately for reward, while the second treatment consisted of flowers plugged with cotton, requiring the bee to rob in order to obtain a nectar reward. Each bee was tested twice, once on each treatment. Results showed first attempts by naïve bees were biased strongly towards legitimate visitation regardless of flower treatment. We speculate this bias is due to the flower’s nectar guides, which promoted legitimate visits. Bees in both groups eventually robbed, but robbed plugged flowers significantly more. Lastly, previous experience affected robbing frequency on subsequent visits, suggestive of learning.