Data from: Commercial Bombus impatiens colonies function as ecological traps for wild queens

1. In response to anthropogenic environmental change, the cues that
animals use throughout their lifecycle to optimize fitness may become
unreliable, resulting in an ecological trap. 2. Here we investigated
whether commercial bumble bee (Bombus impatiens) colonies managed for
early spring crop pollination act as ecological traps for wild
nest-searching Bombus queens by subverting their natural nest usurpation
behavior. 3. An average of 10 dead wild queens were recovered from each
standard colony during the two-week period of the experiment, but colonies
with queen excluders were successful in preventing wild queen deaths. The
use of queen excluders did not impact colony performance in terms of
resident queen survival, colony reproduction, colony weight gain or worker
body size. 4. Sites where wild nest-searching queens were small had higher
rates of failed usurpation, suggesting smaller-sized queens are
disproportionately at risk from failed usurpation. Furthermore, sites
where commercial colonies without queen excluders were introduced for
spring crop pollination had fewer bumble bee visits to a later-blooming
crop compared to sites without commercial colonies. 5. Synthesis and
applications. Our findings reveal a novel mechanism by which commercial
colonies can negatively impact wild bumble bee populations and their
pollination services. At the same time, we demonstrate a simple and
inexpensive risk mitigation tool – a queen excluder – was 100% effective
at eliminating this risk without compromising colony performance.
Commercial colonies used outdoors during the bumble bee nest-searching
period should be fit with queen excluders to prevent negative impacts on
wild pollinator communities and their services.