Our ancestors hunted honey from bees who nested in trees (1). Now, we clear away dead trees, and build over our woodlands (2). This represents a huge loss of habitat for birds, reptiles, amphibians, mammals and insects (3). Homeless wildlife often seek out human structures: sheds, chimneys, roof spaces — and they are usually driven away.

​

Honey bees are one of these struggling species. They reproduce by swarming: the queen flies off with half the colony, leaving a new queen to take over. Both queens have a break from laying eggs, which kills off parasites and diseases. Swarming is healthy! (4) But the swarm needs a home — ideally, a thick-walled tree hollow, about 40 litres capacity.

​

A thick-walled enclosure makes a huge difference to bee health. For instance, research now shows that insulated bees do not need to cluster around the queen to keep her alive in winter. Clustering in a tree hollow only happens when the outside temperature hits -40C. Clustering is the bees’ last resort. (5)

​

Tom Seeley, Professor in Biology at Cornell, has shown that many more of our assumptions about honey bee health need revising. In a tree hollow, the colony controls its temperature and raises humidity to keep brood healthy, with minimum energy expenditure. The bees need less honey to get through winter, and are less susceptible to disease and parasites. Feral colonies in trees survive better than beekeepers’ colonies in thin-walled hives (6).