Honey Bees Modulate Their Olfactory Learning in the Presence of Hornet Predators and Alarm Component

PLoS One. 2016 Feb 26;11(2):e0150399. doi: 10.1371/journal.pone.0150399. eCollection 2016.

Abstract

In Southeast Asia the native honey bee species Apis cerana is often attacked by hornets (Vespa velutina), mainly in the period from April to November. During the co-evolution of these two species honey bees have developed several strategies to defend themselves such as learning the odors of hornets and releasing alarm components to inform other mates. However, so far little is known about whether and how honey bees modulate their olfactory learning in the presence of the hornet predator and alarm components of honey bee itself. In the present study, we test for associative olfactory learning of A. cerana in the presence of predator odors, the alarm pheromone component isopentyl acetate (IPA), or a floral odor (hexanal) as a control. The results show that bees can detect live hornet odors, that there is almost no association between the innately aversive hornet odor and the appetitive stimulus sucrose, and that IPA is less well associated with an appetitive stimulus when compared with a floral odor. In order to imitate natural conditions, e.g. when bees are foraging on flowers and a predator shows up, or alarm pheromone is released by a captured mate, we tested combinations of the hornet odor and floral odor, or IPA and floral odor. Both of these combinations led to reduced learning scores. This study aims to contribute to a better understanding of the prey-predator system between A. cerana and V. velutina.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehydes
  • Animals
  • Appetitive Behavior
  • Arthropod Antennae / physiology*
  • Avoidance Learning / physiology
  • Bees / physiology*
  • Conditioning, Classical / physiology
  • Feeding Behavior
  • Female
  • Flowers
  • Learning / physiology*
  • Memory / physiology
  • Odorants*
  • Pentanols
  • Pheromones / chemistry
  • Predatory Behavior
  • Reward
  • Smell / physiology*
  • Species Specificity
  • Sucrose
  • Wasps*

Substances

  • Aldehydes
  • Pentanols
  • Pheromones
  • nonanal
  • Sucrose
  • n-hexanal
  • isoamyl acetate

Associated data

  • Dryad/10.5061/dryad.4H263

Grants and funding

This work was supported by the Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, and the CAS 135 program (XTBGT01) of Chinese Academy of Science, China National Research Fund (31260585) to Ken Tan. Thanks to the support of CSC-DAAD Postdoc scholarship to Zhengwei Wang. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.