f hives in a 10-km radius of 3 apiaries I help with:
211 at Hawkwood, on the west edge of Epping Forest;
437 at Hackney Marsh;
489 at Stoke Newington
This suggests that as you go further into London the number of hives increases. I'll be interested to see what data on population and forage the LBKA comes up with.
We shouldn't only be talking about looking after honeybees, however. There are 240-odd native UK bee species, a fair few of them present in London gardens. In fact the honeybees kept by London beekeepers tend not to be native; their genes have generally come more or less recently from Italy and the northern Balkans, often via New Zealand. There seems not to be a lot of knowledge about the relations between farmed honeybees and native wild bees – e.g. competition for forage, diseases transmitted. So the keeping of honeybees as an ecological action (or gesture) raises interesting questions.
Planting forage would encourage a range of solitary and bumblebee species as well as hoverflies, butterflies and moths. If you can get urban workers to enjoy sitting in a garden and learning to tell the difference between honeybees, hoverflies, wasps, bumbles and the hairy-footed flower bee, and thinking about how we depend on them – well, that'd be worth doing.…