Mining bees – why do they mine?

Although there is in fact a large number of different bee species, we most readily recognise bumblebees. They are the poster boys and girls of the pollinator world, beloved by us humans for their plump furriness. To investigate bees is to quickly become drawn into a beguiling world, where mining bees are only one of many possible obsessions.

Take for instance the tree bumblebee. It’s a good one to watch out for and was seen recently by one member of staff in the North East in the nest box in his back garden. The tree bumblebee is one of those species that has changed its range. Recently it was only found in southern England but it is now increasingly recorded here. And although we have fewer trees old enough to have cavities, it does well out of our habit of providing nest boxes for birds.

Or what about the wool carder bee – currently one of Crathes’s Fantastic Five. It’s not impossible to see but it is a wondrous find, with its yellow spots down its sides – you might even witness its habit of gathering fibres from plants for nest material (from where it gets its name).

At my house, a modern building, early in the season I am used to seeing bees entering the ventilation grills of my home. Are they, as I have suspected, mason bees? Mason bees like nail holes or soft, pitted brickwork and are known to use buildings in this way. I would be pleased to have them yet I’ve not seen any evidence for them nesting, only their incessant curiosity, noseying in and out of the grill.

On the sandy paths of the dyke and the pondside walk, the solitary bees proliferate. It really is difficult to tell how many there are. They manage to evade the footsteps that helped create their habitat and then duck into their burrows so fast that it’s impossible to get a good view. Even when you wait patiently for them to re-emerge, they seem to bide their time. Look at them closely and they may be looking at you. They can tell when you’re watching them. Maybe they understand that they should not reveal their nest-place.

Why are they called solitary bees? Because the queen, after laying her eggs, leaves the nest, never to return. This is unlike social bees such as bumblebees and honey bees, who remain to produce further offspring. And do solitary bees sting? Well, they can do, but generally they’re a peaceful bunch.

And so why do mining bees mine? Well, maybe it’s for protection. Since they are solitary bees, they lack the benefit of safety in numbers. They may share burrow entrances but they will always have separate accommodation underground – there’s a lot going on beneath those tiny holes in the path.