Wolf, Stephan ; Mcmahon, Dino ; Lim, Ka ; Pull, ChristopherIST Austria ; Clark, Suzanne ; Paxton, Robert ; Osborne, Juliet
Pathogens may gain a fitness advantage through manipulation of the behaviour of their hosts. Likewise, host behavioural changes can be a defence mechanism, counteracting the impact of pathogens on host fitness. We apply harmonic radar technology to characterize the impact of an emerging pathogen - Nosema ceranae (Microsporidia) - on honeybee (Apis mellifera) flight and orientation performance in the field. Honeybees are the most important commercial pollinators. Emerging diseases have been proposed to play a prominent role in colony decline, partly through sub-lethal behavioural manipulation of their hosts. We found that homing success was significantly reduced in diseased (65.8%) versus healthy foragers (92.5%). Although lost bees had significantly reduced continuous flight times and prolonged resting times, other flight characteristics and navigational abilities showed no significant difference between infected and non-infected bees. Our results suggest that infected bees express normal flight characteristics but are constrained in their homing ability, potentially compromising the colony by reducing its resource inputs, but also counteracting the intra-colony spread of infection. We provide the first high-resolution analysis of sub-lethal effects of an emerging disease on insect flight behaviour. The potential causes and the implications for both host and parasite are discussed.
This study was funded jointly by a grant from BBSRC, Defra, NERC, the Scottish Government and the Wellcome Trust, under the Insect Pollinators Initiative (grant numbers BB/I00097/1 and BB/I000100/1). Rothamsted Research is a national institute of bioscience strategically funded by the UK Biotechnology and Biological Sciences Research Council (BBSRC).
Wolf S, Mcmahon D, Lim K, et al. So near and yet so far: Harmonic radar reveals reduced homing ability of Nosema infected honeybees. PLoS One. 2014;9(8). doi:10.1371/journal.pone.0103989
Wolf, S., Mcmahon, D., Lim, K., Pull, C., Clark, S., Paxton, R., & Osborne, J. (2014). So near and yet so far: Harmonic radar reveals reduced homing ability of Nosema infected honeybees. PLoS One, 9(8). https://doi.org/10.1371/journal.pone.0103989
Wolf, Stephan, Dino Mcmahon, Ka Lim, Christopher Pull, Suzanne Clark, Robert Paxton, and Juliet Osborne. “So near and yet so Far: Harmonic Radar Reveals Reduced Homing Ability of Nosema Infected Honeybees.” PLoS One 9, no. 8 (2014). https://doi.org/10.1371/journal.pone.0103989.
S. Wolf et al., “So near and yet so far: Harmonic radar reveals reduced homing ability of Nosema infected honeybees,” PLoS One, vol. 9, no. 8, 2014.
Wolf S, Mcmahon D, Lim K, Pull C, Clark S, Paxton R, Osborne J. 2014. So near and yet so far: Harmonic radar reveals reduced homing ability of Nosema infected honeybees. PLoS One. 9(8).
Wolf, Stephan, et al. “So near and yet so Far: Harmonic Radar Reveals Reduced Homing Ability of Nosema Infected Honeybees.” PLoS One, vol. 9, no. 8, e103989, Public Library of Science, 2014, doi:10.1371/journal.pone.0103989.