When the weather becomes colder, bees huddle. For more than a century, humans have been designing our beehives with thin walls, in the belief that the huddling behaviour was good for the health of the brood and control of mite infestations.
But a new study has shown we have been completely wrong: bee huddling is a last-ditch attempt to stay alive.
Wild honeybees spend winter in tree cavities, insulated by thick-walled tree hollows, 15cm or more wide. But much of our understanding of bee behaviour has come from observing them in thin-walled (1.9cm) wooden hives.
Derek Mitchell, from the University of Leeds, modelled heat loss across a bee huddle to understand if this behaviour helped keep them warm. Previously, it had been thought the huddle helped insulate bees from the cold, but Mitchell’s results, published in the Journal of the Royal Society Interface, showed the closer the bees became, the faster the heat flowed between them. Rather than helping the bees to stay cosy, the huddling behaviour appears to be a survival tactic, sharing warmth and attempting to keep the bees on the outside of the huddle above the critical 10C (50F). Turns out that bees need cosy homes, too: time for a beehive redesign.
