Bees under attack?

[E G]

Last night, while watching bees visiting our campanulas I noticed that the bumble bees were being pestered by a smaller insect who would follow them from flower to flower and apparently attack them by flying in behind them and aiming for the lower end of the bee's abdomen. The bee flew off but the insect remained and settled on a leaf. This happened several times. I wasn't able to take a photo but the insect was about half a centimetre long and had a noticeably light coloured face. Sorry I can't be any more specific than that. Does anyone have a clue as to what I was watching?

[charlieb]

Maybe a Stylopid? See Strepsiptera

[eucera]

Sounds like another bee to me. This is behaviour of the male Anthidium manicatum, the so called "Wool-carder bee"

[Waveney One]

I have noticed more dead bumble bees on the ground this year than I remember from previous years.

[aeshna5]

I saw a Comma chasing a bumblebee round the garden when I got home this afternoon. Obviously being territorial.

[Africa]

I agree with eucera, I got the first A. manicatum male today in my garden. It attacked honey bees and Bombus pascuorum which had got used to feed freely in my large Stachys patch. The honeybee was quite persistent though and came back a few times. Male Carder bees have several 'spikes' at the end of their abdomen and this is what they aim to the other bees when they attack. They can injure or kill other bees with them, but most of the time they scare them away. The reason of this aggressive behaviour is that males are territorial and soon after they emerge they establish a patch they patrol and defend from other bee species and other male Carder bees. This way female Carder bees can feed with little competition and the male gets to mate with them. Bumblebees and bees will tend to avoid the flowers visited by the Carder Bee. They are truly fascinating bees to watch!

[eucera]

Have you ever seen Anthidium kill anything? This is often repeated but I have never found a soul who has seen this (except the person who originally put the story about)

[JRsbugs]

I have a bed with Campanula species, visited by some bumblebees and other bees, but mainly Magachile willughbiella and another Megachile species. There is often a male chasing other bees, they hover behind the 'intruder' bee as it enters the flower, then attack. I have a pic of one attacking a bumblee while feeding on Lupins last year.

I can upload a pic if you wish, it could be Megachile or as suggested Anthidium. The male Megachile has a lot of white hairs on the face.

Janet

[E G]

Many thanks to all of you who tried to throw light upon my darkness. It would be great to see JRsbugs's photo just to see if it's the same wee critter.

[eucera]

Megachile willughbiella is another good candidate. These are particularly fond of Campanula flowers.

Their aggression is much less obvious than that of Anthidium. As an identification guideline, there are no yellow markings on the abdomen of male M. willughbiella