Determinants of honeybee hive survival within cities and its use to monitor urban biodiversity: a Canadian study

Abstract Cities are shown to provide favourable conditions for western honeybees (Apis mellifera) by protecting them from agricultural pesticides and offering a greater diversity of flora. Nevertheless, bee populations continue to decline in many urban areas, posing threats to plant reproduction and urban biodiversity, especially as many now promote urban beekeeping as part of their conservation efforts. While current research primarily focuses on the causes of bee colony collapse, including pesticide exposure, climate change, and habitat fragmentation, little attention is dedicated to urban apiculture and factors associated with the survival of honeybees within cities. Here, we analyse data from 3,694 honeybee hives in Montreal and Toronto to assess the effect of urban and environmental factors on hive survival. We find ground-level ozone concentrations, elevation, and the number of surrounding hives to be negatively associated with hive survival, which may point towards an issue of hive saturation. Conversely, vegetation density and the COVID-19 pandemic are positively associated with the likelihood of hive survival, emphasizing the effect of urban air pollution. These findings highlight the need for urban planners to consider neighborhood-scale environmental factors to support conservation efforts and identify potential venues for enhancing bee survival within cities beyond existing urban beekeeping initiatives.