Tree Bumblebees

[scipio]

We have had bumble bees 'swarming' around our eaves for well over a week, a behaviour I have never seen before. They never seem to pitch and enter a nest. I tried to take some photos but the movement is very rapid and continuous.
Then on Springwatch last night there was a bit on Tree Bumblebees (Bombus hypnorum) and having looked at the website at
Have you seen the Tree Bee?
I am convinced that mine are Tree Bumblebees.
My photo is here:
-> Wildlife
Click on it it enlarge it
Is anyone else seeing them? They are quite distinctive, even to a non-expert like me

[ChrisJB]

Fascinating Scip. I look forward to the day they make it up north to Lancashire and my neck of the woods. Swarming bumble-bees, how marvellous. Thanks for pointing out the webpage too.

Regards, Chris

[eucera]

These certainly sound like B. hypnorum to me too....

Check out the pages of the Bees Wasps & Ants Recording Society (BWARS Home Page) who are running their annual call for information on this species. Full details are on the website, and these include a map showing the known range (based on data received) AND details of how to submit records.

Please take the trouble to pass on the information

Best wishes, Stuart
(Chairman, BWARS)

[scipio]

Stuart,
I've sent you my observation as requested.
Have also managed to get a pic of the individuals:

and

Thanks for the confirmation and interest.

[eucera]

email received and data mapped!

many thanks for this - much appreciated

Stuart

[scipio]

Stuart
You asked if I had seen any with black thoraxes. Well this picture shows that some are loosing their hair leaving a black patch.

Is it male pattern baldness
Will try a bit of video tomorrow.
I looked through my photo data this afternoon and see my earliest pictures date from 1st June so I am guessing I noticed them 'swarming' about 3 days before that but didn't have a clue what I was looking at.
And they are still doing it although there only seemed to be about 5 tonight.
I will keep my eyes on them.

[eucera]

The "swarming" is almost certainly male bumbles, which detect the pheromones of virgin queens inside the nest. I have had about 5 around my nest box entrance today

[scipio]

Originally Posted by eucera

The "swarming" is almost certainly male bumbles, which detect the pheromones of virgin queens inside the nest.

I've read that before but it seems a terribly inefficient way of carrying on.
There has been a fast moving 'swarm' outside my nest for over two weeks now, usually with over 10 bees. They are always there when I look up. If they are still waiting for a future event they have wasted a lot of energy and the pheromone is being wasted.
Of course it would be a different story if a virgin queen flew the nest each day but it seems rather early in the season for new nests to be created although that seems a more likely explanation.
This continuing event is very noticeable and high in energy as this video shows:
Flickr: ChrisWarren2009's Photostream

[eucera]

Bombus hypnorum is a short cycle species, and a second generation is often raised (but in a new nest). I have a nest in my garden, and there are males whizzing about the entrance. I also noticed a few queens emerging too (at least 3 today).

[scipio]

We had no Bombus Hypnorum nests last year (hence the 2-year gap since my last post) but this year we have 3. Well 2 are (were) on my neighbours house and one on mine, which is in the same place as the original one.

I now need some advice. My neighbour was having his soffits and fascias replaced and when the bees started to frighten the fitters (although no stings were reported) they got a pest controller to 'remove' one of the nests.
My neighbour is now planning to do the rear soffits where the second nest is.
How long would he have to wait before the nest disperses naturally?
I may be able to persuade him to wait if it is only two or three weeks.