Using the Solitary Pollinator Osmia lignaria to Bridge Agricultural Practice and Ecological Theory

With global pollinator populations in decline and colony collapse disorder threatening honey bee colony loss, understanding the biology and management of alternative pollinators has become increasingly urgent. Although commercially managed species-particularly honeybees and a few bumblebee species-have been studied extensively, the vast majority of bee species (~80%) are solitary. As such, solitary bees provide a more appropriate foundation for informing conservation and management strategies than their social and eusocial counterparts. In particular, the native North American Blue Orchard Bee Osmia lignaria Say (Megachilidae) has received increasing attention as a viable pollinator for a wide range of crops. However, solitary bee species such as Osmia remain underutilized as model systems for linking behavioral ecology to pollination function, despite their growing use in agricultural systems. In this synthesis, we review current knowledge on Osmia lignaria's developmental plasticity, nesting behavior, foraging strategies, pollination services, and major stressors. We place special emphasis on how environmental conditions and management practices influence its performance as a crop pollinator and as a model organism for ecological research. We also identify key knowledge gaps to help guide future ecological research and inform more sustainable pollination strategies in both agricultural and natural systems.