Are agricultural landscapes a buzz kill? Bumblebee trait diversity and species persistence

Background/Question/Methods

As land cover change drives species extinctions worldwide, preserving species with a diversity of traits is an important aspect of overall biodiversity conservation and maintenance of ecosystem functioning. The impact of land cover types on trait diversity of a vital pollinator group, bumblebees (Bombus), is unclear. We address this knowledge gap by asking whether nesting location, body size, and phenology affect persistence of 14 bumblebee (Bombus) species across 35 agricultural and 22 semi-natural land cover types in Southern Ontario, from 2015 to 2017.

Results/Conclusions

We preliminarily find that species diversity declines in agricultural sites over time while remaining constant in semi-natural sites. Nesting location does not impact persistence across land cover types. Relative abundance of kleptoparasitic and above-ground nesting species declines over time in both agricultural and semi-natural areas, while it does not in underground nesting species. Body size does not appear to impact abundance across land cover types nor over time. Earlier-emerging Bombus species appear less likely to persist than later-emerging species. These findings highlight the importance of considering trait diversity, rather than simply species abundance, in conservation strategies.