Honey bees (Apis mellifera) in anthropogenic landscapes: A citizen-science study of colony success in relation to urban and agricultural land use

Honey bees (Apis mellifera L.) extract enormous quantities of floral nectar and pollen from their environment and forage at an extremely large spatial scale. These traits suggest that the success of honey bee colonies would be sensitive to landscape composition at scales corresponding to their foraging range. Such a relationship has been observed in bumble bees (Bombus spp.), whose foraging biology is similar to that of the honey bee. While loss of foraging habitat is widely cited as a likely cause of honey bee decline, and several studies of honey bee spatial foraging patterns indicate floral resource limitation under some circumstances, studies explicitly relating honey bee colony success to landscape composition are notably absent. Using a citizen-science approach, we measured the success of fifty colonies over their first active season using the metrics of food accumulation, wax production, adult population, and brood population. We then quantified the surrounding landscape of each colony in terms of urban, field crop, forest, and pasture land cover. We also considered two hive management variables: beekeeper experience and supplemental feeding. Canonical correspondence analysis revealed no predictive relationship between landscape composition and colony success. Instead, colony success was predicted by beekeeper experience and supplemental feeding, suggesting limitation by internal colony conditions rather than external floral availability. The robustness of honey bees to wide variation in landscape composition may be due to their unique ability, not shared by bumble bees, to communicate the location and quality of resource patches using the language of the waggle dance.