Sampling bee communities using pan traps: alternative methods increase sample size

Bees play an important role in natural and agricultural landscapes and increased interest in these pollinators has lead to an increase in studies designed to monitor bee populations across the globe. Many studies investigating bee diversity use pan traps (colored plastic bowls filled with soapy water) as a cost-effective trapping method. Here we investigate how alternative pan trap designs (both the size of the traps, and the addition of nectar guides) affect the number of specimens collected. We find that larger pan traps collect more specimens than small and medium sized traps, and that the addition of nectar guides can significantly increase the number of specimens collected. Increased sample sizes can lead to a better understanding of patterns of bee diversity, which can lead to more informed management decisions.