Assistant Professor University of Tennessee Knoxville, Tennessee
Background/Question/Methods
Aggregating ground nesting bees are critical and often understudied pollinators that may be increasingly threatened by anthropogenic change. One indicator of aggregation health may be its parasite load. We explored the relationship between the health of ground nesting bees aggregations and nest parasitism (kleptoparasism) for the genera Andrea, Colletes, and Anthophora. To quantity this, we collected adult host bees and their kleptoparasites using sweep net transects of 17 meters for a total of 15 minutes per aggregation across eastern Tennessee. For each aggregation we also measured nest density and adult body size.
Results/Conclusions
The most frequently collected parasites were Nomada (Apidae), Leucophora (Anthomyiidae), and Bombylius (Bombyliidae). The kleptoparasite to host ratio ranged from 0 to 2.22 per aggregation. Our preliminary data support the hypothesis that higher male to female ratios in the host species may reduce total kleptoparasite loads and show a potential relationship between proxies for aggregation health (e.g. nest density and adult body size) and kleptoparasite density. Understanding the intricasies of ground-nesting bee aggregations and their relationship with parasites is paramount for native bee conservation and our study aims to clarify how host-parasite interactions influence bee health.
