Biology & Sustainability
Assessing Risk of Conopid Parasitism in Foraging Bumblebees Using Radio Frequency Technology
Document Type
Oral Presentation
Location
Indianapolis, IN
Subject Area
Biology & Sustainability
Start Date
11-4-2014 1:15 PM
End Date
11-4-2014 2:30 PM
Sponsor
Wendy Tori (Earlham College)
Description
Bumblebees (Bombus spp.) play a vital role in pollination worldwide. Bumblebees demand large amounts of pollen and nectar to maintain and grow their colonies, and colony size is closely related to survival and reproduction. Foraging trips may be risky due to parasitism by endoparasitoid conopid flies (Dipera: Conopidae) that use bumblebees as hosts. Conopid parasitism can impact foraging activity, reduce worker lifespan, and limit colony success by reducing the worker force size. This study examined how cumulative time spent away from the colony influences the risk of parasitism experienced by individual bumblebee workers during mid-summer when conopid flies are seasonally abundant. Using radio-frequency identification (RFID) technology to monitor the activity of individuals, we found that workers that spent more time away from the colony had an increased likelihood of becoming parasitized. Our results demonstrate that bumblebees experienced a substantially greater risk of parasitism in early July than in mid-June. In mid-June, bumblebees incurred a 50% chance of becoming parasitized after ~30 hours of flight time, whereas in early July this probability was reached after only ~17 hours of flight. We estimated that during peak parasitism in July, nearly every forager would be infected during the time required to fully provision a single offspring. Because bigger colonies are more likely to reproduce, conopid parasitism could have significant impact on colony success. Further research is needed to investigate how conopids might influence the success of bumblebee colonies and the role that colony size might play in surviving seasonal attacks by this parasitoid.
Assessing Risk of Conopid Parasitism in Foraging Bumblebees Using Radio Frequency Technology
Indianapolis, IN
Bumblebees (Bombus spp.) play a vital role in pollination worldwide. Bumblebees demand large amounts of pollen and nectar to maintain and grow their colonies, and colony size is closely related to survival and reproduction. Foraging trips may be risky due to parasitism by endoparasitoid conopid flies (Dipera: Conopidae) that use bumblebees as hosts. Conopid parasitism can impact foraging activity, reduce worker lifespan, and limit colony success by reducing the worker force size. This study examined how cumulative time spent away from the colony influences the risk of parasitism experienced by individual bumblebee workers during mid-summer when conopid flies are seasonally abundant. Using radio-frequency identification (RFID) technology to monitor the activity of individuals, we found that workers that spent more time away from the colony had an increased likelihood of becoming parasitized. Our results demonstrate that bumblebees experienced a substantially greater risk of parasitism in early July than in mid-June. In mid-June, bumblebees incurred a 50% chance of becoming parasitized after ~30 hours of flight time, whereas in early July this probability was reached after only ~17 hours of flight. We estimated that during peak parasitism in July, nearly every forager would be infected during the time required to fully provision a single offspring. Because bigger colonies are more likely to reproduce, conopid parasitism could have significant impact on colony success. Further research is needed to investigate how conopids might influence the success of bumblebee colonies and the role that colony size might play in surviving seasonal attacks by this parasitoid.