Flight of the bumble bee: Buzzes predict pollination services.

Area of Science:

• Ecology
• Bioacoustics
• Pollination Biology

Background:

• Wild and managed bee populations are declining due to multiple factors, impacting crucial pollination services.
• Effective bee population management requires widespread, intensive monitoring, which is often cost-prohibitive.
• Passive acoustic monitoring offers a potential low-cost, non-invasive alternative for tracking bee activity.

Purpose of the Study:

• To evaluate an inexpensive, passive acoustic survey technique for monitoring bumble bee behavior and pollination services.
• To determine the relationship between bumble bee flight buzz characteristics and pollinator functional traits.
• To assess the efficacy of acoustic data in predicting bumble bee activity and pollination success.

Main Methods:

• Flight cage experiments and literature review to correlate flight buzz frequency with pollinator traits.
• Development of a Computational Auditory Scene Analysis algorithm to quantify buzzes from acoustic data.
• Comparison of acoustic estimates with visual observations of bumble bee activity.
• Pollinator exclusion experiments to link buzz density to seed set in alpine plants.

Main Results:

• Bumble bee flight buzz frequency correlated with body size and tongue length, traits influencing pollination.
• Acoustic buzz density strongly correlated with visual estimates of bumble bee density (r = 0.97).
• Buzz density significantly predicted seed set in two alpine forb species when bees had access.

Conclusions:

• Acoustic signatures of bumble bee flight can be reliably deciphered to monitor bee activity.
• Passive acoustic monitoring effectively predicts pollination services for bumble bee-pollinated plants.
• This technique can assist scientists and farmers in early detection and response to bee population declines.