(1st Place) Testing the impact of bloom phenology on bee community composition across diverse cropping systems

Wild bees provide economically important pollination services to many specialty crops, but the taxa responsible for pollination varies between crop systems. Understanding bee community composition is an important step in protecting pollination services. Composition of pollinator communities is determined in part by bees’ activity periods and their overlap with crop bloom. We quantified how crop seasonality shapes pollinator community composition in 4 specialty crops, including spring-blooming apples and blueberries and summer-blooming tomatoes and watermelons. We hypothesized that bloom phenology acts as a selective filter, structuring the composition of pollinator communities across diverse cropping systems. While we expected to find crop-specific differences in pollinator communities, we predicted that, overall, communities would be similar between crops with overlapping bloom times and distinct between spring and summer crops. Community composition was determined in each crop using specimens collected in pan traps in 2022 and 2023. Contrary to our prediction, PERMANOVA analyses indicated that pollinator communities were significantly different in both years for apples and blueberries. All crop pairs were significantly different, except for tomato and watermelon. SIMPER analysis indicated that Lasioglossum (dialictus) species were important for distinguishing pollinator communities in most crop pairs. Apple and blueberry communities were differentiated from one another in 2022 by Andrena carolina (an Ericaceae specialist), while in tomatoes and watermelon, Melissodes species were important contributors to difference. These results demonstrate that while bloom phenology plays a role in determining pollinator communities, in the case of spring blooming crops, other crop-specific factors supersede phenological overlap, resulting in distinct communities.