Bumblebees in March

Astound your friends with your entomological knowledge this month.  Simply point to any bumblebee you see and say with absolute certainty “oh look, it’s a female”. How can you be sure?   The fact is that the only ones flying this month are females, known as queens.  They emerge about now to feed on early nectar and pollen before hunting out a nest site which is likely to be made in a hole in the ground or abandoned small mammal burrow. So make sure you have plants like crocuses and Mahonia in the garden.  All the males died off last year when the cold weather set in, while the females hibernated through the winter carrying the eggs for this year’s colony. As furry insects, bumblebees are well adapted to cold northern climates and are often the first bees to start flying, being able to withstand the cold weather March can sometimes throw at us. It acts as insulation.

Your friends might be impressed but it could lead to a more challenging question such as what species it is. 

Though there are 24 species of bumblebee (3 species are already extinct in the UK) and some of them are difficult to tell apart, they don’t all fly very early.  So your sighting could be the white-tailed bumblebee (Bombus lucorum) which are striped black and yellow; one yellow stripe on the thorax and one on the abdomen, with a white tail. Another species with a white tail is the buff-tailed bumblebee (Bombus terestris) but its bands are more orange than bright yellow.  Identifying bees is much more difficult than butterflies or dare I say it, birds!
Another early flyer is the tree bumblebee (Bombus hypnorum).  Like the Ivy bee which you are most likely to encounter in the autumn, it

 wasn’t seen in the UK until 2000.  Despite their name they are most likely to be nesting in bird boxes than tree holes – maybe there just aren’t that many tree holes in urban sites? When a tree has a hole it’s deemed dangerous and down it comes.  I haven’t yet found out what you do if you find a colony in your nest box, when you think a blue tit or sparrow should be the occupant. I think the answer is put up another box!  They are easily the most distinctive to ID with all three types having the same orange thorax and white tail. Queens will feed on white dead nettles, so save a patch of them in a corner in your garden, veg patch or allotment too! 

The Fields Studies Council has many good guides and courses; the Big 8 crib sheet  is excellent for bumble bee identification.  It illustrates the 8 species you are most likely to encounter. If you do see one this early, let us know the exact location with a picture if possible or explore Nature’s Calendar which aims to track the changing seasons and the effects of weather and climate change on wildlife in the UK, using citizen science.