I said in my last post that there didn't seem to be many butterflies around this year, either here in Milan or in my garden in London. Well, for bees Milan is just the same - I've not seen any this year. The hard winter again, or more problems of colony collapse disorder?
But when I was in London I was pleased to see that they were absolutely everywhere - and snapped away like crazy taking photos.
There were some honeybees (at least I think that's what this one is)...
But the vast majority were bumblebees. Which made me realise that I didn't really know very much about bees at all. How many types were there? What were the differences ? I knew that honeybees lived in colonies but that there were also solitary bees. What was the difference? How did you recognise them? And where do the bumblebees fit in? Were they social or solitary? And was CCD affecting all types of bees or just the honeybees?
So I did some research - and found some excellent websites, which are listed below. I'm not going to regurgitate it all, but I was surprised to find out that in the UK alone there are some 300 different species of bee - about 270 of which are solitary.
Solitary bees make a nest by burrowing into soil, soft brick or whatever. The female then gathers pollen and nectar, forms it into a patty, pops it into the far end of the burrow, lays a single egg on top and then seals that section of the burrow up before doing the same in the next bit - and so on up to the end. The very last egg is always male (bees have this strange ability to decide the sex of their children). The eggs hatch, and the larvae consume the food left for them and then pupate. The pupae all hatch at the same moment but the male, being closest to the exit, is the first to burrow his way out. He then waits for his sisters, mates with them, and the whle thing starts all over again. All a bit incestuous, but there you are.
So how do you identify a solitary bee? Well, by Googling them, obviously. I think this may be one ...
... and possibly this one too. Or is it just some sort of fly desperately trying to pretend he's terribly fierce?
Bombus bumblebees, on the other hand, are social and live in colonies. Unlike the honeybees, however, they don't store large quantities of food and all but the young already fertilised queens will die off in the winter. The queens hibernate and then in the spring secrete beeswax to form little cups which they fill with nectar and pollen, laying an egg in each one. As the new workers reach maturity, they start to collect food for the later-hatched larvae. But having only one season in which to form, the colonies remain quite small - whilst a honeybee colony may contain up to 70,000 individuals, bumblebee colonies rarely exceed about 300 and are often smaller.
But what I didn't realise was that there are nine species of Bombus bumblebee in the UK, some very common others quite rare. What were mine? To me, they all looked quite different. This one seemed to fit the description of the most common British type - the Buff-tailed Bumble bee. But the others? The colouring and stripes didn't sem to match. So I sent a few photos off to the Bumblebee Conservation trust (see below) for identification. Would I find that my garden was a home to rare bees?
Nah... the answer came back after a couple of days. All common as muck Buff Tailers.
Except for one. So far there has been no answer for the little one below who I found happily feeding off my borage. Could the delay be because I've discovered something rare? Doubt it. More likely that you just can't see enough from the photo to tell. My own suspicion is that this is not a Bombus bumblebee but a Psithyrus or cuckoo bumblebee - there are six species but don't ask me which this is. These are sneaky. They lay their eggs in the nests of the Bombus bumblebees and let them do all the work. You can tell the difference between the Bombus and Psithyrus bumblebees by looking at their legs. The cuckoos don't need to store food for their larvae and so don't have pollen sacs on their legs - sacs which you can see clearly in the photos of some of the Buff Tailers in the other photos, but which don't seem to be present here.
Will I be right? We'll see. If I get an answer I'll add it in the comment box below. But in case they don't get back to me - any bumblebee experts out there?
Read some more
Bumblebee Conservation Trust Bumblebee Identification
Natural History Museum Bumblebee Identification Guide
The British Bee Keepers Association : bees4kids - The Importance of Bees
Watanabe, M. Colony Collapse Disorder : Many Suspects, No Smoking Gun