Bee-fly Question

[GuyF]

Hi everyone,
A few days ago I had this Bee-fly in my flowerbed and I spent about half an hour watching it, they're fascinating little insects.
I was wondering what the grey thing on it's bottom is?
I've seen other pictures in the Gallery of Bee-flies which don't have this, and I was wondering whether it was a male/female difference. I am fairly confident this is a female bee-fly because it seemed to be laying eggs in the flowerbed.
Can anyone help?
Guy

[Wild-Woman]

From what I've read Guy, I think the grey thing is a 'bag' containing dust that is used to coat the eggs as they are produced so that they are disguised on the ground long enough, enabling them not to be predated. The grubs enter a solitary bees nest and are parasitic to that bee.

I've been searching for info myself, as I've found them so fascinating, but apart form the Heath bee-fly, which is protected, there's not a huge amount. Perhaps we should write our own book Guy.

I expect there's some great big entomological book somewhere with it all in.

[eucera]

I have assumed that the dust (which you can see females scooping up) is used to weight the sticky eggs.

The Heath bee-fly is a BAP species but I've just checked Schedule 5 of the Wildlife & Countryside Act (Animals) and I note that the species is not protected in UK, and nor are any species of fly... or bee... or wasp...

[GRH]

Though there's still much to be found out about them (and other insects for that matter) they are covered by Alan Stubb's Soldierflies book (as it covers Acroceridae, Asilidae, Athericidae, Bombyliidae (bee flies), Rhagionidae, Scenopinidae, Stratiomyidae, Tabanidae (horseflies), Therevidae, Xylomyidae and Xylophagidae).

Greg

[GuyF]

It's strange that we know so little about such an interesting little insect, I was looking in some books and it seems that there are still some mysteries surrounding their lives.
Perhaps we should write a book on them, although it seems that they're difficult little things to study
Thanks for all the information you've given me, it did look like she was using it when she was laying her eggs.
As for Heath Bee-flies, as I liked my garden Bee-flies so much I might go and have a look for some of those soon, I live near the Dorset heaths which must be a good place to look for them. In my book it says they are active in July and August, so I've got a while to wait for them to come out!
Thanks again for your help,
Guy

[LindaB]

I cant help with giving any further info Im afraid, but just wanted to say that this thread is very interesting - providing the bits of info that are so hard to find (oh and another good book recommended).

Since finding my bee-flies recently I have to admit to being equally fascinated by them as all of you are. I could watch them for hours


Linda

[eucera]

Originally Posted by GuyF

~SNIP~
As for Heath Bee-flies, as I liked my garden Bee-flies so much I might go and have a look for some of those soon, I live near the Dorset heaths which must be a good place to look for them. In my book it says they are active in July and August, so I've got a while to wait for them to come out!

No need to wait! You could get out and look for Bombylius discolor (common on calcareous downs on the Wilts/Dorset border and doubtless in Dorset too (flying NOW). The west Dorset undercliffs are home to Bombylius canescens too (A little later in the year).

B. minor is active from about 20 July, and you need sandy trackways on the Purbeck Heaths. They can be very abundant in good years. Listen for the very high-pitched hum of the beating wings.

Good hunting

Stuart

[The Woodman]

Fantastic, this forum job.
In 15 years at this property I've never seen a bee fly but two days ago watched one moving faster than a bumble bee amongst forget- me- not flowers for some minutes before flying off.
I get the feeling that all the experts are hovering in the background....

[GuyF]

Originally Posted by eucera

No need to wait! You could get out and look for Bombylius discolor (common on calcareous downs on the Wilts/Dorset border and doubtless in Dorset too (flying NOW). The west Dorset undercliffs are home to Bombylius canescens too (A little later in the year).

B. minor is active from about 20 July, and you need sandy trackways on the Purbeck Heaths. They can be very abundant in good years. Listen for the very high-pitched hum of the beating wings.

Good hunting

Stuart

Thanks very much for that information, if I get the chance I will definetely go and have a look for these bee-flies, and hopefully come back with some pictures. I was going to go to Badbury Rings today, with chalky soil, I wish I had now as there might be Bombylius Discolor there, it sounds like the right habitat.
Thanks again,
Guy

[eucera]

If anyone is interested in checking out the distributions of these things, I strongly advise a visit to the NBN Gateway at National Biodiversity Network Gateway

You can browse the species lists easily, access an interactive map.... query the records, zoom in on sites, overlay land cover and SSSI boundaries etc. Well worth using this magnificent site.

Stuart