cuckoo bee – Enviro-Mentalist

Bumble Bee Walk No 3

I’m in to the third month of my bumble bee walks and I am becoming obsessed with watching the weather to see which is likely to be the optimum Saturday or Sunday to go out and look for bees.

This time it was a bit breezy, but the sun did put in an appearance and it was generally warm (that was a week ago and it has been quite chilly and wet this weekend so it was a good call).

My walk is divided into five sections, according to the type of habitat. I tried to choose some near houses, some near fields and hedges and some near disused land. Again though, there were not many bumbles about. In the first section there wasn’t a lot flowering other than hawthorn which I was surprised to notice was pretty much bereft of any insect life. I assume something must pollinate it or there would’t be any berries, but it wasn’t popular on this Saturday. I returned a score of null points for this bit.

I wasn’t very hopeful for the second section as it is along a path besides some new housing (which they are just finishing off). Fortunately I was in luck and spotted three different types of bumble bee. Next up was a long stretch with fields of crops on the left and houses on the right, mainly grass, but hedgerows, umbellifers and dandelions were scattered liberally. It was the dandelions that rescued me on this stretch, with a red-tailed and white tailed worker gathering pollen and nectar.

Off back into the houses and we found loads of mason bees, but also some bumbles, including a couple of queens feeding on lonicera. Fortunately this seems to be a favourite with both housing developers and bees, otherwise we would have drawn a blank again.

On the final stretch we have some disused land – it was a field and I’m sure they will build some houses on it, but for the time being it had some vetch, birds-foot trefoil and dandelions flowering on it. I counted three carder bees and a red-tailed on the birds-foot, but also my first cuckoo bee of the year on a dandelion – a queen red-tailed cuckoo bee Bombus rupestris. It was quite lethargic which allowed me to get a good look at it’s back legs – all hair, no shine or pollen baskets. Coupled with its very smoky wings and this was definitely a cuckoo bee.

So another disappointing bee walk. I’m starting to get concerned about the lack of bees (I’m not even seeing huge numbers in my garden). It can’t have been the weather this time as we spotted lots of butterflies – including orange tips and even a brimstone. At least by doing this regularly we will hopefully find out if it is indicative of a decline or just that there still aren’t many workers out yet.

Today I learned … that not all bees collect pollen on their legs.

I already knew about the existence of cuckoo bees. These are bees that lay their eggs in the already provisioned nests of pollen collecting bees so that they don’t have to bother collecting pollen themselves. This means that they don’t have the hairy pollen baskets on their legs. This is one way of differentiating them from the hosts that they have evolved to mimic. However, an interesting article by Mike Edwards in the excellent British Wildlife Magazine gave me an insight into different types of bees and why their efficiency at pollinating plants varies so much.

The standard belief is that there is a mutually beneficial relationship between plants and pollinators whereby plants provide nectar as a foodstuff for the pollinating insect. In turn the bee moves pollen from the male part of the flower to the female whilst collecting it to take back to the nest for their larvae. This article revealed that this only occurs with certain species and that in many cases the plant is robbed!

What I didn’t know before today is that some bees, such as this white faced bee, are almost hairless and eat the pollen and nectar they collect before flying back to the nest; therefore denying the flower its rightful pollination.

The best known bees are the honey bees and the bumble bees, however, I also learned today these are not very efficient pollinators. In some cases these bees manage to get the nectar and avoid the reproductive parts of the flower and therefore don’t pollinate it at all. However, even if they do collect the pollen in the baskets on their legs, they need to wet it with nectar so that it doesn’t fall out. This means that the pollen isn’t readily transferred to the female part of the flower. Honey and bumble bees are, in effect, pollen robbers!

Whilst googling cuckoo bees for this short article I also came across this cool picture on Wikipedia. A cuckoo bee asleep, using its mandibles to hold on – what a fantastic shot! Until today I didn’t realise that bees did this!

Bumblebee Identification

I joined the Bumblebee Conservation Trust last year following a Summer trying to photograph them which made me realise how interesting and different they all were. Couple that with all of the coverage regarding the plight of the honeybee which also extends, although for different reasons, to other pollinators, and I decided that it was time I discovered more about the bees in my garden.

Fast forward a year and with my new found interest in invertebrates I started to discover there were more bees about than I had realised, including my favourite, the red-tailed bumblebee, and others such as the wonderfully named hairy footed flower bee. Despite many attempts and lots of photos, I still felt at a loss when it came to positively identifying them. When I saw an advert for a bumblebee identification session at Leicester University on a Sunday afternoon then I signed up straight away.

I arrived early and thought I would go and try and find some bees to photograph – as you would (and, amazingly, got some photos I was really pleased with). They had some lavender beds in their herb garden which we literally buzzing as well as some other plant such as echinops which also seemed pretty popular.

Anyway, back to the course. It was run by a lovely lady called Maggie, who is obviously obsessed by bees. She went through the lifecycle of bees, some of the differences between them and included a list of plants that she had created and which she had subsequently grouped according to how many species of bee visited them. I came away realising that I had to be a little more choosy about the plants that I am putting in the garden and with some ideas for research that I could also undertake. First, however, I need to be able to identify them.

I was hoping to come away from a couple of hours amongst the flowers with the ability to recognise the common bumbles, the big six. But, there are queens, workers and males – so the big six became 18, and then there are the cuckoo bumble bees – another 4 types with males and females so we are now at 26! Suddenly it was not as easy as I had hoped. (Cuckoo bumbles don’t need workers as they parasitise the nests of particular bumbles so use their workers to care for their offspring.) Then, as the bees get older, just like us they fade and get greyer, well, paler – so then all the descriptions seem to go out of the window!

Did I come away knowing many of the 26? Well, we did find four of the big six – but they are mainly males and workers at this time of year, the queens are in the nests. So, I can recognise a carder bee (a little fluffy, ginger bee), and the red-tailed bumble bee, I will also have a go at the buff and white tailed bees (the male white-tailed bumble bees are particularly lovely – see photo above), but we didn’t see the early or garden bumblebees, so I will carry on looking. However, we did find three or four species of cuckoo bee, which I may have seen before and just not realised what they were (such as the one in the photo on the right)! So, although I am not fully convinced that I can get the big six yet, I have now a better idea, and think I can have a go at finding cuckoo bees. I will also be planning some winter research and some more bee-friendly plants for next year.