When should bees be flower constant? An agent-based model highlights the importance of social information and foraging conditions

1. Many bee species show flower constancy, i.e. a tendency to visit
flowers of one type during a foraging trip. Flower constancy is important
for plant reproduction, but the benefits of constancy to bees are unclear.
Social bees, which often use communication about food sources, show
particularly strong flower constancy. 2. We aimed to better understand the
benefits of flower constancy in social bees and how these benefits depend
on foraging conditions. We hypothesised that sharing social information
increases the benefits of flower constancy because social foragers share
information selectively about high-quality food sources, thereby reducing
the need to sample alternatives. 3. We developed an agent-based model that
allowed us to simulate bee colonies with and without communication and
flower constancy in different foraging environments. By varying key
environmental parameters, such as food source numbers and reward size, we
explored how the costs and benefits of flower constancy depend on the
foraging landscape. 4. Flower constancy alone performed poorly in all
environments, while indiscriminate flower choice was often the most
successful strategy. However, communication improved the performance of
flower constant colonies considerably in most environments. This
combination was particularly successful when high-quality food sources
were abundant and competition was weak. 5. Our findings help explain why
social bees tend to be more flower constant than solitary bees and suggest
that flower constancy can be an adaptive strategy in social bees.
Simulations suggest that anthropogenic changes of foraging landscapes will
have different effects on the foraging performance of bees that vary in
flower constancy.