I’d like to see if we could use the Forum to gather some observations about “Queen Dispersal Flights”. These can sometimes be spotted, when queens start to get active in the spring.
Might we be able to record some relevant data such as:-
Time of day.
Place - & rough geography.
Number of queens seen.
(Were they alone or in groups?)
Let me explain!
One of the hidden skills that queen bumblebees possess is an ability to make “Dispersal Flights” and so move away from their area of origin, or over-wintering, before they establish a colony.
(It must be important in maintaining Genetic Diversity.)
I think I’ve seen Dispersal Flights happening on a small number of occasions.
The bees were flying high (say 20 - 50 ft [6 - 20 m]) and very obviously not in the least bit interested in nest-searching or foraging. They seemed to be intent on flying away from, or past where you see them.
Here’s some examples that I have seen:-
I first spotted such activity in the New Forest, in early spring, when I realised that queens were flying high over the heathland and across a wide valley. It was a sunny day and a good many B. lucorum queens were nest-searching in the area. The high queens were probably of this species too.
On another occasion I saw a B. terrestris queen flying high and determinedly across the river Thames in South Bucks. It was a cold windy and cloudy mid-afternoon.
And finally I saw a small B. rupestris queen spiral up, then away at high level after I picked her up for safety from a road close to my house. It was a mild, overcast early afternoon.
(I guess it might be that she had been resting, and maybe decided she didn’t like the look of me, but she certainly had no interest in staying in the area !)
The standard Bumblebee Textbooks mention Dispersal as an important but little known feature of behaviour. Prof. Goulson’s book “Bumblebees, Behaviour, Ecology & Conservation” tells on p193 of observations in Scandinavia when 900 queens of B. lucorum were passing through a 150 m strip in an hour!
Such dispersal activity must have helped our newest bumblebee B. hypnorum, the Tree Bumblebee to have attained it’s astonishingly successful colonisation of England over some 10 years or so.
Any comments ?
That’s very interesting Clive. I don’t recall ever noticing that. I’ve seen them feeding and I’ve seen them flying low as if searching.
I’ll certainly look out for it though
Hi Clive, there is an interesting paper here that discusses queen dispersal distances.
The data showed that Bombus pascuorum and B. lapidarius queens can disperse by at least 3 and 5 km, respectively.
Estimation of bumblebee queen dispersal distances using sibship reconstruction method
Mol Ecol. 2010 Feb;19(4):819-31.
Thanks for your feedback.
I recognise several of the authors of the paper !
This is very interesting and fits with an observation from a few years back where I live. Wycombe, in South Bucks.
Wycombe is a “Valley Town” with several large park green spaces in the valley floor and much urban development up the sides of the valley and onto the flat land around.
We get all the Big 7 (6+hypnorum) species here in the valley, but one summer in the last few years there was a distinct lack of Red Tailed BBs (B. lapidarius). Usually there are plenty of them in the spring working Chives and in the summer working Lavender (in gardens) white clover etc down in the park: so their almost total absence was very noticeable.
During that time when we went for walks a few miles away out in the countryside, where there is some residual Chalk Grassland, there were masses of Red Tails as usual - despite our significant dearth a few miles away.
The following summer the Red Tails were back in the main parks & green spaces & gardens in the town at the normal high levels.
So I think this could well be another example of Dispersal by colony founding queens.
The spring bumblebee queen activity splurge in my home area seems to have died down now.
I never spotted any bees that looked as though they were setting out on a high level flight that was going to be a journey; but I did see several flying about 10 m up, having just left off foraging on big Pussy Willow (Sallow) trees.
They were flying quite fast though, so it could have been dispersal following a food stock-up.
The geography of the place didn’t let me see how far they went, or if they kept going.
As to red-tailed bees, I’ve only seen one so far and she was on high ground ~ 1 km outside the main Wycombe valley; so I’ll just have to wait to see what level of red-tailed presence we get in the valley floor this summer.