Data from: Floral diversity enhances winter survival of honey bee colonies across climatic regions

In temperate climates, winter can be an arduous time for eusocial insects.
Survival of honey bee colonies during winter depends on a delicate balance
between hive thermoregulation, managing the food reserves, and timing the
onset of the new worker bee generation. Winter survival is influenced by
several factors, most notably colony size, Varroa mites infestation levels
and the availability of stored food. Importantly, the climatic conditions
and floral resources of the previous foraging season can also impact honey
bee health and colony strength before hibernation. This study, conducted
across Europe, examines how landscape composition and weather conditions
affect winter survival of honey bee colonies. It uses pollen diversity as
a proxy for flower resource quality and available foraging days as a
climatic variable to understand their causal relationships to winter
survival. We found that landscapes with higher percentages of agricultural
areas increased pollen diversity collected by honey bees in autumn,
whereas higher percentages of semi-natural areas increased the diversity
during summer. Spring and autumn pollen diversity was the main driver for
winter survival success, emphasizing the importance of diverse flower
resources for colony health. While we did not find a statistically
significant effect of weather on winter survival, trends suggest potential
influences, warranting further research to confirm and clarify the role of
seasonal foraging on colony health. Our study highlights the critical role
of including floral resource diversity and weather conditions, in a
comprehensive framework for studying honey bee hibernation. It suggests
that increasing plant diversity around apiaries and implementing
agricultural practices that enhance floral resources can significantly
improve winter survival, with honey bee colonies benefiting even in
landscapes with higher agricultural activity, distinct from the needs of
other pollinators.