A good spring for Osmia cornuta

A good spring for Osmia cornuta

My bee houses have been rewarding me with lots of activity from the Osmia cornuta in the past weeks.  I’m sure they don’t need any help to find hollow nesting places but when they choose my hollow bamboo canes or drilled-out wood I have the pleasure of watching their antics.

The first I know that some bees have hatched is the frantic activity of the males.  This 17 second video gives you an idea of what it looks like.

I admire the tenacity of the males who guard the holes against all comers.  You can get the idea in this 16 second video.

The male can be easily recognised by the little tuft of white hair on his head.  They are around several weeks before the females eventually hatch and then the excitement really mounts.

The mating is not an elegant affair and this pair managed to get stuck in the tube in a sort of impasse where neither was prepared to cede defeat.

I noticed this mating pair under the box and I was surprised by the females stoic non-resistance.  That was until I saw the photograph on the computer and noticed that the male had a firm grip on her wings and back legs.

The male eventually decided to dismount and release her.

The female is a very attractive bee and is larger than the male, which is not uncommon in bees.  She lays her eggs in hollow stems or crevices and supplies the future larvae with pollen for nourishment.  She pushes the pollen firmly in place with the help of two little horns on her head.

The horns are under the antennae and as the horns are black they are difficult to see amongst the black hairs of her head.  They are best seen in a photograph.

Once the females have emerged they begin their frantic search for the perfect hole.  Despite the abundance of choice from our point of view the females have a need to explore.

Eventually one will meet her high requirements and the egg laying and pollen collection will begin.

Pollen collecting is a serious business even if putting it in place can get a bit messy.

Isn’t nature wonderful ???

Isn’t nature wonderful ???

O.cornuta emerges 19.3.15

The first male Osmia cornuta emerged on the 19 March.  Since then he has had to put up with dull, rainy days and colder than normal temperatures.  I know that the females emerge a few weeks later but he seems completely unaware of this and faithfully visits the holes where I presume he can smell the females, still comfortably tucked up in their cocoons.

IMG_8809.male O.cornuta resting (1)

The males also play out the waiting game sitting in any of the empty holes of the bee hotel, hoping for the sun to come out or better still for the females to emerge.

Anthophora aestivalis...

It’s not just the Osmia males that are in waiting but the Anthophora are waiting too.  (I think this may be an A. aestivalis because I’ve seen its legs and it is not a plumipes.)

2 male o. cornuta (1)

But with all that waiting I think some of them must get a bit confused.

2 male o. cornuta (2)

The male in the hole is desperately trying to explain he is not a female.

2 male o. cornuta (3)

Giving up in desperation he retreats.

2 male o. cornuta (4)

Then gathers his strength to be more assertive and push his way past.

O.cornuta female

Strangely, while all this, “Shuff off, I’m not a female” was going on, I noticed a black head emerging slowly from a hole not far beneath them.  It did make me wonder that if I had noticed and they had been waiting for it to happen for two weeks that they might have been a bit quicker on the uptake.

O.cornuta fem with male

Eventually, without me having to shout, “She’s behind you!”, one of them spotted her.

O.cornuta female emerges

The first Osmia cornuta female of the season emerged!

O.cornuta mating with 3

Having had two weeks to prepare for the big event, I was a bit disappointed with what followed.  I just couldn’t see this position as efficient for increasing the population of solitary bees.  They tried the threesome, never the less, until the top one gave up.

O.cornuta male waiting on side lines

The second male moved off to watch the proceedings from the side lines.

O.cornuta getting suck in the hole

I felt the female was getting pretty fed up and then she made a clever manoeuvre towards a free hole.

O.cornuta getting suck in the hole (1)

This did not deter the determined male who hung on regardless.

O.cornuta getting suck in the hole (2)

The female managed to squash both of them into a stalemate, whereupon the male gave up.

O.cornuta female shakes free

Having shaken off her admirer the female emerged onto the surface of the log to take stock of her position.

O.cornuta female warns off male

A male tried to take advantage of her but was warned off with a defensive position and mandibles wide open in warning.

O.cornuta female grooms

With a few butt wiggles and a quick groom the female took off.  She will soon enough be mated and I am sure return to start her own nests.

The males that I have seen patrolling the bee hotel with impatience will have to get their technique improved if they hope to pass their genes to the future generation.  So far I would rate them at 10/10 for winter survival, spring survival and persistence but they are going to have to do better at their next attempt at copulating.

Anthophora furcata nests in my bee hotels

Anthophora furcata nests in my bee hotels

When I first started putting up bee hotels in the garden I so much hoped that I could attract some of the Osmia species to come and nest in them.  I knew that putting up the nests was one thing but it was the bees that did the choosing where to nest.

Well, it hasn’t been quite what I expected.  I have been so overwhelmed with the uptake of these man-made sites because I have had so many different species of bees nesting in them.   In addition, solitary wasps and parasitic flies have used them too.  So identification is quite a problem.

This slideshow requires JavaScript.

I really was not expecting such an array of bees to nest in the bee hotels and it is difficult to identify them.  I have not read about Anthophora nesting in bee hotels although over a year ago I was sure I saw Anthophora plumipes using one of the drilled logs in the early spring time.

Anthophora furcata

I reluctantly decided to capture her leaving her nest in September.  She is getting old and her wings are tattered but the three submarginal cells are clearly seen.  Working through ID keys she has a round head with inner margins of her eyes more or less parallel.  The basal vein is more or less straight and she is about 1.5 cm.  The lower borders of the second and third submarginal cells are more or less equal.  She has black legs with scopa on her hind legs – so I have reached the identification of Anthophora!

Anthophora furcata beside ruler

Here she is getting measured approximately beside a ruler.

Anthophora furcata

Following a further key for Anthophora I note that she has an entirely black face.

Anthophora furcata last tergite

Then bingo!  The last tergite is red orange!  I wish all bees had a little special something that made their identification clearer.  Another name for this bee is the fork-tailed flower bee.

For some excellent photographs and some more information check out Steven Falk’s excellent site.

I would not say that my Anthophora furcata is smaller than the Anthophora plumipes I see here.

Another point of interest is that A. furcata is in the subgenus Clisodon.  The charactristic of this subgenus being that the female has a tridentate mandible which could be associated with nesting in rotting wood.  The other member of this subgenus A.terminalis readily nests in pithy stems.  I think the A. furcata around me are not averse to nesting in the stems of the bee hotel but they do seem to prefer the drilled wooden holes which they continue to excavate and clear out.

 

Birth of a fly

Birth of a fly

This slideshow requires JavaScript.

These photographs date back to 31 May 2014.  May is a very busy month in the bee hotels.  The bee hotels are much busier than I had ever suspected.

On 24 May three different species of bee were emerging at the same time so it was difficult to concentrate on what to focus on.  The bees emerge daily and I visit with my camera in hand.

On the 31st I saw something starting to emerge.  It looked different but I was hoping for yet another bee species.  Then I thought perhaps a solitary wasp but I think what I have here is a parasitic fly, perhaps a Leucophora species.

I have seen what I think are Cacoxenus indagator , with their red eyes, around the hotels in the past but these are tiny fruit fly sized creatures.  The hole that can be seen in the photograph of the fly has a diameter of 7-8 milimetres, which makes the fly coming up to 2 cm. long

Fly

Unfortunately, I saw a similar for the second time on 28 September 2014.  It was examining my newest bee hotel.  Because I had put it up so late in the season only Anthidium manicatum has nested here.  This sort of bee hotel can be opened so it is something I can look out for when I open it.

Any information anyone has on these flies would be greatly appreciated.

 

 

A Megachile emerges

A Megachile emerges

1-Rose meg 4.9.13 19-57 (2)

On the fourth of September last year I noticed a hole in my bee hotel had been beautifully sealed by carefully arranged sections of rose petals. (See Some Megachile).

1-1 Rose petal hole_0527

On the 24 of May this year I noticed a hole had been chewed in the centre of it.

1-2 24.5.14 1920_0532

I could not resist removing the remains of the rose petals to get a better look.  A new little bee was making her way into the world.  However, it was 19.20 and domestic duties called and the light was fading for photographs.

1-3 Rose hole 25.5.14 11.04_0536

It was 11.04 the next morning before I was able to get back to my bee and she seemed just to be waking up.

1-4 25.5.14.11.11_0542

Seven minutes later and she was not  making an enormous progress.

1-5 25.5.14.11-13_0543

Then two minutes later there is movement from the hole above her.

1-8 other further out 11.26_0568

Now which one should I focus on?  The other one is larger and not the same species.  Very interesting but I do not want to lose my rose petal bee.

1-9 other out 11-26_0569

After a couple of minutes hesitation the big bee launches itself into the air.  Sorry about the blur but it was the best I could do.  I have no idea what species it was.

1-10 At edge 11-38_0586

Back to my rose bee that has been emerging gradually for the last  34 minutes.  She seemed to have a considerable difficulty pulling herself through the little hole she had chewed in her leaf capsule that had been her home since last September.

1-11 On outside 11-39_0596

Finally after watching and taking photographs of her for 35 minutes she emerges onto the outside of the log.

1-12 Going 11-39_0600

She paused momentarily before taking off.   After this first one, many others emerged from the same hole in the following few days, usually taking less time to exit than this first one.  Sometimes it looked as if the bee next in the queue was giving encouragement from behind because as one took off, another little head appeared at the hole.

However, I am not certain what species of leaf cutting bee she is.  Megachile centuncularis are well known for their use of rose petals which points me in this direction.  It is a common bee and I have seen bees looking like Megachile centuncularis on the bee box last year.

1-13 26.8.13 Mummy head

Could this be Mummy emerging from another hole in the log on the 26 August last year?

1-14 26.8.13 Mummy (2)

I base my identification of the bees I saw filling the holes last August on Steven Falk’s wonderful photographs and information

Megachile centuncularis female - Cross Hands Quarry, Warwickshire 2010a

, he says females can be distinguished from some other British species by the bright orange pollen brush that remains orange haired to its tip (black-haired at tip in some others).

Well, even if I cannot be 100 percent sure of my French bees at least I can say I breed beautiful bees!

 

Some Megachiles

Some Megachiles

1-Megachile arches

Megachiles collect their pollen on brushes under their abdomen.  The colour of these hairs can often be used to help identify the species.

1-Pollen brush

But as with anything else used in identifying bees – it has its limits.  The underside of the bee can look the same colour as the pollen when it is heavily loaded.

1-Megachile brings back lots of pollen 29.8

That’s a good load of pollen!

1-Megachile chews leaf into size

They are commonly know as leaf cutter bees as they choose already existing holes and line them with leaves to lay their eggs with a pollen and nectar store before sealing the cell with more leaves.  They choose leaves that can be manipulated easily from trees such as lilac, ash or cherry or flower leaves such as roses or even rose, poppy or geranium petals.

5 September 2013

5 September 2013

You can see her determination to fit this piece where she wants it.  This shot was taken in my home-made bee hotel and I recommend trying one out as they are fascinating bees to watch.

1-IMG_3261..asleep.26.8.13..9.49 a.m.

This one was a late riser.  Perhaps she had had a busy building job the previous day.  It was 9.49 a.m. on the 26 August 2013 and she was still asleep with the last leaf she had brought home acting as a blanket.

1-Megachile Rose petals 4.9

On the 4 September 2013 one of the bees finished off their nest with rose petals – class!

1-IMG_4538. Megachile centuncularis

I’m going to go for a photographic ID (i.e. not an expert one) and say that this is Megachile centuncularis on my dahlia at the beginning of October 2013.  These are the bees I believe are nesting in my bee hotels.  In addition, the wing venation checks out with the images I’ve seen.

1-Tiny black Megachile.12.8

But there are other bees that look like Megachile around, like this tiny black one on Centaurea nigra in early August.

1-Birds's Foot Trefoil.25.6

And this one with green eyes on Bird’s Foot Trefoil in late June (I think probably, Megachile leachella).  Although these last two may be tricking me with their ventral pollen brushes as Osmia and Lithurgus bees have ventral pollen brushes too.

1-Megachile close

But I’m as satisfied as I can be that she is Megachile centuncularis.