The birds and the bees, part deux

After the last blog post, we have another bee-related sighting. Though this time the expression 'the birds and the bees' can be used figuratively too.

Leaving the office yesterday, Toby the warden came across a mating pair of bees on the path. Really rather impressive in size, the female had a much smaller male on her back. Normally they fly into the air to mate. But I guess the chap had been eating too many pies as she was having real trouble getting off the ground. She even tried crawling up Toby's leg, to try to gain some height.

Now, these weren't ordinary bumble bees. These were tree bees. Or Bombus hypnorum, if you want to get fancy with scientific names. Common on the continent and through Asia, they weren't part of British wildlife until 2001, when they were spotted in Wiltshire. Since then they have done very well, colonising most of England (particularly in the south and east) and getting into Wales.

One reason for this rapid spread (whilst our native bumblebees have been suffering declines) might be their choice of nesting place. Honey bees live in hives, with thousands of bees. Bumblebees on the other hand have much smaller colonies, usually numbering less than a hundred insects. Our more familiar bees might nest in an old animal burrow or a grass tussock. But tree bees are quite happy to nest in other places, often higher up off the ground. Holes in old trees would be one venue. or, as many people are finding, in bird boxes. Lots of people have these in their gardens, and it is becoming an increasingly common sight to find bees not birds living there.

This is no bad thing. With native bumblebees on such a decline, tree bees are taking on a lot of their pollination duties. They can keep your garden looking lovely. Plus you are giving a home to some wonderful nature. But one word of warning. Whilst they are normally very good-natured and docile creatures, they are protective of their nests. Either fiddling with the nest itself, or causing vibrations that affect it (eg by doing some hammering nearby) might cause the bees to decide their nest is under threat. Then they will all come out at once, determined to defend it to the death with their stings. So give them a little room, and enjoy the sight of them buzzing around from flower to flower. The colony will die out in autumn, and then you can clean out the bird box.

So how do you recognise tree bees? Well, they have a unique colour pattern amongst the larger British bees. The top part of the body (the thorax) is a solid tawny to reddish brown colour. Sometimes the hairs rub off, making that bee look even darker. The bottom part of the body (the abdomen) is a dark charcoal grey to black. And there is a very clear, clean white tip to the tail.

So there you have it. Tree bees. Why not look out for some in your garden today. And remember they are just one part of nature that we should all try to give a home.