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IN town this month The lowdown on... Bumblebees Professor Dave Goulson This was what first got me interested in bumblebees, 20-odd years ago: I was sitting watching bees in a park near where I lived, and I saw these bees flying up to flowers but then not landing on them, veering away at the last second, and doing that perhaps two or three times before they actually landed on a flower. I thought - what’s wrong with the ones they’re not visiting? It turns out, every time a bee lands on a flower, she accidentally leaves behind a footprint. Subsequent bees come along, and essentially they give each flower a quick sniff, and if a flower smells of a recent visit by another bee then they don’t bother landing, because that bee will have taken the nectar already. Bees do all sorts of clever things that, for their size, are pretty astonishing. They have a magnetic compass built into their brain; they can also use the sun as a compass. Certainly their navigational abilities would put people to shame, which is pretty impressive when you think that they are quite tiny and their brain is considerably smaller than a grain of rice. Bumblebees have an annual life cycle. They’re started by a single queen, who builds a nest, on her own to start with, until she’s raised her first batch of daughters. Then it grows through the spring and summer, and the nest dies off in the autumn, and only leaves behind new, young mated queens. Honeybee nests live for years and years, so they have to survive the winter. That’s why they make honey. They have to store up enough honey to provide that huge workforce with something to eat for the four or five months of the year when it’s too cold to get out and about. Bumblebees don’t go through the winter as a nest, so they don’t need to collect honey. These declines [in bee numbers], they’ve been going on probably for 80 years. The danger’s pretty obvious, in the sense that roughly a third of the food that humans eat depends upon pollinators of one sort or another, of which bees are the most important. Our diets would be very poor without the help of bees. And natural ecosystems would essentially collapse without pollinators. So it couldn’t be much more important to look after them. Am I optimistic? Well, a lot of conservation stories are really doom and gloom, and people feel helpless, because they can’t do anything themselves about polar bears, or the rainforest being felled, and so on. The nice thing about bees is that people can do something themselves to help. They can grow some bee-friendly flowers, they can not use any insecticides in their garden, they can join in citizen-science schemes to help record how well our bees are doing. If we can get enough people involved, then that really would make a difference. As told to Steve Ramsey Prof Dave Goulson is the author of A Sting in the Tale, and founder of the Bumblebee Conservation Trust. He’s speaking at Seedy Saturday, 6th Feb, Town Hall. 31