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Abstract BackgroundEvolution has shaped diverse reproductive investment strategies, with some organisms integrating environmental cues into their reproductive decisions. In animal societies, social cues can further influence reproductive decisions in ways that might support the survival and success of the social group. Bumble bees are a lineage of eusocial insects wherein queens initiate nests independently. Bumble bee queens enter their eusocial phase only after successfully rearing their first offspring and thereafter exhibit an increased rate of egg-laying. We tested the idea that during bumble bee nest initiation, queen reproduction is socially context-dependent and under the control of social conditions in the nest. ResultsOur findings reveal that in the bumble beeBombus impatiens, queen egg-laying follows a dynamic, stereotypical pattern and is also heavily influenced by social group members. During the initial stages of nest initiation, accelerated egg-laying in queens is associated with the presence of workers or older larvae and pupae. Moreover, workers are required for queens to maintain increased levels of egg laying across the nest initiation stage. We also confirmed a previously-described pattern where queens temporarily decelerate egg-laying early in nest-founding, only to increase it again when the first adult workers are soon to emerge. This “pause” in egg-laying was observed in allB. impatiensqueens as well as in additional species examined. ConclusionsOur results support the idea that eusocial systems can employ socially context-dependent control of queen egg-laying as a reproductive strategy. In some solitary-founding lineages, including bumble bees, queens may reach their full reproductive potential only after the emergence of the first adult workers, who then take over brood care. This stands in contrast to the hyper-reproductivity observed in some eusocial species. The presence of workers and older brood (who will soon eclose) not only alleviates queen brood care responsibilities but may also provide signals that cause queens to increase their reproductive output. These phenomena may allow queens to adapt their reproductive output to the conditions of the colony. Broadly, these findings highlight the dynamic interplay between social conditions and reproduction in bumble bees. 

ABSTRACT The overwhelming majority of research on wild bumble bees has focused on the social colony stage. Nest‐founding queens in the early season are difficult to study because incipient nests are challenging to find in the wild and the foundress queen flight period is very short relative to the entire nesting period. As a result, natural history information on foundress queens is exceedingly rare. New methodological approaches are needed to adequately study this elusive life stage. We trap‐nested wild queen bumble bees in artificial nest boxes in Gothic, Colorado and used a custom‐built radio frequency identification (RFID) system to continuously record queen foraging activity (inferred from entering and exiting the nest) for the majority of their spring flight periods. Foundress queens made frequent, short foraging trips, which tended to increase in duration over the course of the flight period. All queens who produced adult workers ceased foraging within approximately 1 week after workers emerged in the nest. We observed frequent nest failure among foundress queens: Fewer than one quarter of queens who laid eggs in nest boxes went on to produce reproductive gynes at the end of the season. We also report nest characteristics and curious phenomena we observed, including conspecific nest invasion and queens remaining outside the nest overnight. We present this trap‐nesting and subsequent RFID tracking method as a valuable, albeit resource‐intensive, path forward for uncovering new information about the elusive, incipient life stage of wild bumble bees. 

Conservation and management of wild bees is hindered by the variety of ways wild bee occurrence data are recorded, managed, and shared. Here, we present solutions to address this issue and introduce The Wild Bee Data Standard, a standardized means of recording and reporting data associated with wild bee occurrences, including physical specimens and photo observations. This standard aligns with contemporary data management practices widely adopted by the broader biodiversity data community. We propose a set of terms for the standard that describe various features of bee occurrences, including collection method and location, taxonomic verification, and final record storage. We emphasize the importance of providing sampling protocol and effort information with wild bee occurrence data and offer guidance to make this a more common practice. We describe how to translate data not currently aligned with the standard to meet its conditions, and how to upload those data to an accessible online repository. We provide case studies, data entry templates, a glossary of terms, and additional resources to guide new users to implementing the standard. We also present a forum, established as a GitHub repository, to support continued development of the standard. Recognizing the significant change this represents for current data practices, we outline the benefits for the bee research and conservation community that will result from improved data standards. We advocate for making all historical, current, and future bee occurrence data openly available to facilitate more rigorous and comprehensive research, conservation, and management of wild bees. This contribution is part of a series developed in association with the U.S. National Native Bee Monitoring Network to standardize bee monitoring practices.