Good evening. We begin tonight with the weather news.
It was pretty bleurgh today, actually, with stormy winds bringing in repeated bands of thick black cloud and rain, and occasional interludes of brilliant sunshine that tended to lull you into thinking everything was now back to normal, so you ventured outside in a t-shirt only to realise five minutes later that you’d made a serious strategic error. In Iceland they tell visitors, “If you don’t like the weather just wait twenty minutes, and it’ll have changed to something else,” – and today in the Shire it was much the same.
The swirling wind and wildly variable light made outdoor macro (or as in this case, lazy woman’s 500mm pseudo-macro) photography difficult – WILL NO-ONE EVER STOP TO CONSIDER THE POOR PHOTOGRAPHER???!!! – but I didn’t get where I am today by making sensible choices such as architectural or indoor portrait photography. So I stomped round the garden in a mardy mood, snapping what I could, and then extended my beat to the rest of the village – which got me a few thousand extra steps, but precisely no extra images. Luckily, some of the photos I’d taken in the garden came out surprisingly well, including an entire set of this very fresh, rather beautiful, but extremely dozy bee.
The clue to her identity is that patch of bright lemon-yellow between the black pile of her abdomen and her white tail: she’s a Vestal Cuckoo Bee (Bombus vestalis), and she’s pretending to be a Buff-tailed Bumblebee queen. Her job is to find and invade an appropriately-sized Buff-tailed Bumblebee nest (too large and the defending workers might overwhelm her; too small and by the time she’s taken over there may not be enough workers left alive to take care of her eggs), displace its queen, and take over the nest in her place. The bulk of her eggs will develop into queens, with just a few males to supply the genetic needs of the new queens from nearby nests.
The only thing about this that confuses me about this otherwise quite straightforward picture is that according to the books it’s either too late or too early to be seeing such a fresh Vestal queen. Received wisdom is that the generation of females that has overwintered emerges between March and April, so as to be able to seek out Bombus terrestris nests once they have a good colony of workers, but before they get too big. So it’s much too late for her to be an overwintered female, and in any case she’s far too plush and sleek to have just emerged after months living in a hole somewhere. However, the offspring of the spring invaders aren’t expected to appear before about July, which puts her about a month ahead of schedule to be one of those. So maybe this is yet another sign of the warming climate, and all those authoritative guides will need to be amended – especially in view of the fact that the Buff-tailed Bumblebee is now believed to be double-brooded in many southern areas, and even triple-brooded in the very warmest places. So perhaps this queen won’t be spending the rest of the summer feeding up before going into hibernation, but will be soon be out looking for a second-brood Bombus terrestris nest, with a view to staging her home invasion before the summer is out.
One last point before I stop wittering. I’m really not very good at sexing bees unless they show obvious sexual dimorphism, and while male B. vestalis sometimes have a straggly yellow belt, it’s not a reliable feature. But I’m as sure as I can be that this specimen is female because I’ve counted her antennal segments (three times), and I can’t get them beyond 12 no matter how hard I squint. If you’d like to join in this game – and you know you really don’t have anything better to do – start at 1 with the stalk that comes out of the head, which is the scape; then 2 is the little nobbly joint called the pedicel; after which the segments of the long flagellum are 3-12 in a female and 3-13 in a male. If you decide to try it, and disagree with my conclusion… please tell someone else. I thank you.
R: L2, C10, D13.
