Tag Archives: leechwell garden

A thug on the Lamb’s Ears

I walk through our local community garden (The Leechwell Garden) most days in summer just to have a look at the flowers and insects but I know that, if I am there late morning, the sound of children playing will brighten the air.  The older children, sometimes along with mum or dad reliving their youth, will be enjoying the fine new play area with its exciting slide.  The younger ones may be messing about on the watery edge of the stream that passes through the garden but it is the sand pit that really hits the spot.   Children love playing in the sand and I often see several family groups clustered about the sand pit; the only thing that seems to deter the children is heavy rain.  It’s a real tribute to the vision of the garden committee that they created something so popular.

Pair of wool carder bees
Male (left) and female wool-carder bees having a rest. One leaf has been well “carded”.

 

The flowers I come to see are across the other side of the garden and, for the past few weeks, I have been loitering near the old stone wall where there’s a large patch of the plant Lamb’s Ear (Stachys byzantina).  It covers the ground with a jumble of silvery-green, velvety leaves and sends up stout, silvery stems bearing clutches of smaller leaves and understated pink-purple flowers.  It’s a pleasant, restful sort of plant creating an old-style, cottage garden feeling but what goes on around these Lamb’s Ears in midsummer is far from restful.

From the middle of June, a dark, chunky bee can be seen patrolling the patch of silvery-green leaves and I spend more time than I should watching him.  Whereas most bees are gentle creatures keeping themselves to themselves, this one is a bit of a thug, oozing anger and aggression.  He is the male wool-carder bee (Anthidium manicatum), mostly black but with yellow markings along the sides of his abdomen, head and legs, reminiscent of the warpaint worn by native American tribes.  He is about the same length as a honeybee but much broader making him quite imposing as he moves quickly about the patch of Lamb’s Ear.  His movement is distinctive, he hovers then moves rapidly to a new spot, hovers, moves, all the time buzzing noisily.  It feels like he is looking for something.  And that’s exactly what he is doing, looking.  Should he spot another male wool-carder bee or a different insect on his patch, he will chase it away by flying directly at it.  I have seen him attack a bumblebee at least twice his size and knock it to the ground.  But, not only is he aggressive, he is armed; the rear of his abdomen sports five stout spines which he will use to injure or kill the intruding insects and there are reports of male wool-carder bees disabling honeybees who dared to feed from their patch.

All this aggressive energy is directed towards protecting the patch of Lamb’s Ear for himself and his harem, for now and then a female wool-carder bee will appear.  She looks very like the male, only a bit smaller; the wool-carder bee is one of the only species in this country where the male bee is larger than the female.  When the male sees her feeding from the flowers he will pounce and, without any preliminaries, mating will ensue. This is a vigorous but brief activity sometimes causing the flower stem to vibrate before the two disengage and go about their business again.  Unlike most solitary bees, where females mate once, wool-carder females undergo multiple matings so that, after a short time, our male will mate with the same female again and should a different female appear he will attempt to mate with her.  One valiant observer went to the trouble of watching an individual male wool-carder in his garden and reported that the bee mated sixteen times in one day.

This focus on the aggressive behaviour of the male wool-carder bee tends to obscure the fact that it is the female that does all the hard work of nest building and egg laying.  The wool-carder bee is a solitary species so that individual mated females build their nests alone, unlike the more familiar social honeybees and bumblebees.  Nesting occurs in preformed aerial cavities in dead wood, in walls or in hollow stems, including the tubes found in bee hotels.  Once she has identified a suitable site, the female strips or “cards” woolly fibrous material from plant leaves with her mandibles (hence the name wool-carder) and takes it back to her nest to line and plug the cavity (see the pictures below).  Lamb’s Ear leaves are a popular choice for “carding” but Great Mullein or Yarrow can also be used.  If you look carefully at the leaves of these plants you can sometimes see bare areas where she has been actively collecting fibres.  Within the nest, she lays eggs and equips them with a mixture of nectar and pollen.  The eggs develop in the nest where they stay until new bees emerge next summer and the whole cycle begins again.

So, if you have a patch of Lamb’s Ear in your garden take a look, there’s a good chance that wool-carder bees will be using it and you too can be enthralled by their antics.

Male wool carder bee
Male wool-carder bee – look at his spines.

 

Male wool carder bee in flight
Male wool-carder bee in flight

 

Anthidium manicatum mating pair
Wool-carder bee – mating pair

 

Wool carder bee collecting fibres
Female wool-carder bee collecting fibres

 

Wool carder bee gathering fibres together
Leaning back gathering fibres together

 

Wool carder bee flying off with fibres
Female wool-carder bee in flight with ball of fibres

 

Possible female anthidium
Female wool-carder bee

 

Male wool carder bee showing spines
Male wool-carder bee

 

Bumblebee on Lamb's Ear
A brave bumblebee feeding from the lamb’s ears

 

Bees in a landscape

I’ve always loved visiting galleries, discovering what an artist has created, but in the first week of May, the tables were turned.  For the first time, I was on the other side presenting a joint exhibition with my artist wife, Hazel.   We called the exhibition, “Bees in a Landscape”, and it was based around Hazel’s semi-abstract paintings of memorable views from the South West of the UK depicting the local landscape in all its glories.  Alongside the paintings, I showed photographs of some of the bees I have encountered in these same locations.   We hoped that the exhibition would raise awareness of the variety, beauty and importance of these beneficial insects as well as showing how we can all support them.

Poster for Birdwood & P.V
The Exhibition Poster

It was more than a year and a half ago that we agreed to put on the exhibition and throughout 2016 I photographed bees and Hazel worked hard on her paintings.  I didn’t spend hours looking for rare examples, I just photographed the bees that I saw, often in local gardens or when Hazel and I were out walking together by the coast.  It has certainly made me look more carefully at insects and flowers when we go out.

As the week of the exhibition approached there were many things to arrange: had we done enough publicity, did we have enough wine for the Private View, had we sent out all the invitations, would enough people come? Fortunately Hazel has a lot of experience in putting on exhibitions.  When we spoke to people in the run up to the exhibition, we detected a genuine interest in the topic of bees and the landscape which was very reassuring.

P1080627
Hanging the Exhibition finally finished!

The most stressful time was “hanging” the exhibition.  All the paintings and photos were ready but we couldn’t get in to the gallery until 1730, the evening before the exhibition opened on the Sunday.  There were a few distractions, and it took longer than we expected to decide how to place the work around the gallery and to mount it on the walls, and we had to come back on Sunday morning to complete the job.  In the end, we finished with just enough time to nip home to change and be back to welcome guests for the Private View.

Totnes women's choir, Viva
Roz Walker and Totnes Women’s Choir Viva singing at the Private View

The Private View is one of those special artists’ events that goes with an exhibition.   It’s a chance to invite friends, other artists, and people with a special interest to share a glass of wine before the exhibition is open to the public.  Many people came and everyone seemed genuinely interested and impressed by the work.  We were also very fortunate that, during the Private View, Totnes women’s choir Viva, sang for us creating a magical atmosphere with their beautiful harmonies.  Led by Roz Walker, and dressed in yellow and black, they sang songs about bees based on poems by Rudyard Kipling, Carol Ann Duffy, Vita Sackville-West and one based on the Finnish epic poem the Kalevala.   We were so grateful that they gave their time to come and sing for us.

gallery 1
Hazel stewarding in the gallery

The Exhibition was open that afternoon and then daily until the following Saturday.  Hazel and I split the stewarding duties which meant we each did a morning or an afternoon in the gallery.  Totnes is a busy place and the gallery is in the centre of town so up to 100 people came in each day.  We both had many interesting and unexpected conversations with visitors and I was very surprised at the warmth and interest shown by people who came to look at the pictures, both landscapes and bees.  On many occasions, I heard the comment:  ” I didn’t realise how many kinds of bee there were in this country and how beautiful they are!”  Hazel found that her paintings evoked memories for visitors: of childhood picnics, happy holidays and even a honeymoon.  The greetings cards featuring images from the Exhibition were also very popular.

gallery 3
Two of the bee pictures (actual size of each picture is A4)
gallery 7
Hazel’s painting of “Bantham – the promise of summer” (two canvases each measuring 60X50 cm)

On the Tuesday, I took a small group on a Bee Tour of the public gardens dotted around the centre of Totnes.  It wasn’t a very sunny day but we had wide-ranging discussions and were able to see some interesting bees foraging on large patches of comfrey and cerinthe including female Hairy-footed flower bees, early and tree bumblebee workers and a garden bumblebee queen.

Soundart
My debut on Soundart Radio

Our exhibition was featured on Soundart, a local community radio station.  One of the presenters interviewed Hazel in the gallery and I went to the studio to talk about bees.  This was an interesting experience, if not altogether satisfactory.  After Hazel’s interview had been played, the presenters asked me about the exhibition and about bees which was fine.  When we got on to neonicotinoids, however, the discussion was hijacked by one presenter.  He challenged the possibility of obtaining “evidence” in scientific investigations of complex systems like bees and after his intervention, the bee discussion petered out which was a shame as there were many other aspects we could have covered.

Hazel and I were extremely pleased with the exhibition.  Many people came to look and we had some fascinating conversations.  Several people made special journeys to visit and talk to us.  People went away knowing more about bees.  What more could you we have asked for!?

For more about Hazel’s paintings click here.  The featured image at the top of this post  is Hazel’s painting “Seal Bay (Brixham from Churston Cove)”.

Birdwood House Gallery  web site can be viewed here

One sunny day does not make a Spring

The sun greets the spring

And the blossom the bee,

The grass the blea hill

And the leaf the bare tree

From “Love and Memory” by John Clare

 

The signs have been there for a while.  Birds singing as though someone told them it’s time to turn up the volume.  Grassy banks dotted with starry yellow celandine flowers.  A green haze of fresh leaves slowly creeping over previously bare branches.  If only the weather would play fair it might be spring.

So, after many days of damp and grey, the sun shone, the air was warm and it was as though a transformation had taken place.  It was also Friday Market Day and, as people wandered between the stalls, they smiled at one another and remarked on the weather.  Two busking fiddlers played pleasing harmonies in the Market Square and, outside the Italian Café, it was not quite Tuscan weather but the beautiful people laughed and smiled in the Devon sunshine.

I wandered down to the Leechwell Garden where, soon after I arrived, my attention was grabbed by a low but insistent buzzing.  On an extensive stand of rosemary growing against one of the old brick walls I saw a real sign of spring. It was a chunky bee covered in rich brown hairs but with a pale nose.  Moving quickly and purposefully among the slate-blue flowers, it collected nectar, buzzing as it went.  This was a male Hairy Footed Flower Bee (Anthophora plumipes), my first one of the year and seeing it lifted my spirits.

Elsewhere in town, I looked at a huge willow (Salix caprea) that has been cleverly pollarded and trained over a wall where its many slender stems drop like water over a precipice.  The tree has been covered in immature, grey “pussy willow” catkins and, recently, these have been mutating into bright pollen-loaded male catkins. Last Friday in the sunshine the tree was very impressive: a mass of yellow flower heads, unruly brushes made from the long stamens, alive with honeybees and a few bumble bees and small flies.  The whole tree buzzed as the sun’s energy was transformed into sound.

When the bumblebees saw me, they flew off in disgust.  The honeybees, however, were drunk on pollen and nectar and either didn’t see me or didn’t care.    Many of them already carried large chunks of orange-yellow pollen to take back to the hive but when they encountered a new flower head they wallowed in it, they almost swam in the stamens.  If they could have expressed pleasure this would have been the occasion.

Later, a light mist crept over the hills to the east, gradually enveloping the town and shutting out the sun.

A plumipes
Hairy-footed flower bee on rosemary

 

willow
The willow waterfall

 

honeybee 2
Honeybee on willow catkin

 

honeybee 1
Honeybee with pollen on willow catkin

 

B hypnorum
Tree bumblebee (Bombus hypnorum) on willow catkin

One of my favourite early spring bees

This year I promised myself I would try to get to know one our early solitary bees. I’d seen them in previous years but I knew there was more to learn so, from early March, I started looking carefully at the flowers in the local community garden, the Leechwell Garden. It was a bit frustrating as spring didn’t seem to know how to get started, rather like a sulky teenager on their way to school. The slow season had its effect on the flowers; there were plenty of primroses and dandelions and some rosemary but the early lungwort, a favourite of my chosen bee, was a bit short on blooms. It didn’t help my mood when a friend phoned to say she had seen one of the bees in a garden in Cornwall.
………………………….

A plumipes on rosemary 2
Male Hairy-footed Flower Bee (A.plumipes) on rosemary, showing the pale facial markings.

 

I had to wait another week after the phone call but eventually I was rewarded. Around lunchtime one sunny but cool March day, I heard a harsh buzz from the direction of some rosemary growing against one of the old stone walls. When I investigated, I saw one of my chosen bees working the disorderly blue-grey flowers, but he saw me coming and promptly flew away. Nevertheless, the spell had been broken and I began to see one or more of the bees each time I visited.
Rosemary and lungwort were their favourites and they moved deftly from bloom to bloom in search of nectar, long tongue often extended in readiness. Pausing to feed each time for a second or so, they emitted an urgent buzz as they moved, sometimes hovering briefly as if to take stock, their wings a pale blur in the sunshine. Despite the rapid staccato movements, I could see that they were roughly the size of a small bumblebee and covered in pale brown hair. Their distinctive, pale facial markings also stood out, reminding me of masked revellers at the Venice carnival.

These were male Hairy-footed Flower Bees (Anthophora plumipes), some of the earliest solitary bees to appear in the UK as winter stumbles slowly away. In this part of Devon, my first sighting was in March, around the time of the Spring Solstice, their presence providing a rather wonderful indicator of the new season. They are partial to lungwort flowers but feed from a wide variety of others. This year I have seen them feeding from banks of rosemary in a seafront garden, from aubretia cascading down an ancient wall and from three cornered leek growing in a long border near the sea. They forage at lower temperatures than many other bees making them important early season pollinators. In a rural setting, they are important pollinators for broad beans.

A.plumipes 3
Male A.plumipes showing hairy leg and foot.

 

I tried to photograph them but they were rarely still, moving very quickly, seeming to object when I got too close, hovering in the air and buzzing loudly as if to frighten me away. After some persistence I managed to get a good photo showing their hairy middle legs and feet, celebrated in their name. The photo also shows their subtly marked abdomen with its alternate pale and dark stripes.
…………………………

A. plumipes 18 04 16
Female Hairy-footed Flower bee (A.plumipes) on lungwort showing orang/tan pollen hairs.

 

By early April, the lungwort was flowering well and the pale brown males were regular visitors to these trumpet-shaped flowers. They were joined by another chunky bee, this one jet-black except for two orange-tan flashes towards their rear. Easily confused with a small bumblebee and surprisingly different from the males, this was the female Hairy-footed Flower Bee. The female bees moved around the flowers as quickly and as edgily as the males, like small mobile black bullets. The splashes of colour come from thick tufts of orange/tan hairs on their back legs. These are their pollen hairs, used for collecting as they visit different flowers. A female with her yellow-loaded pollen hairs is a fine sight at this time of year.

Longcause 2
Female A.plumipes approaching aubretia

 

Longcause 5
Female A.plumipes feeding from aubretia – is that the tongue I can see?

 

The females were just as sensitive to my presence as the males, displaying a belligerent attitude as they hover and buzz aggressively in mid air. Occasionally they would check me out, hovering and looking, darting to right or left, hovering and looking, sometimes circling right round me. Bumblebees sometimes also take a good look, circling around me, even landing on my sleeve but this is a dialogue whereas my interaction with the Hairy-footed Flower Bee felt more confrontational.

For a few weeks, I saw a mixture of males and females feeding on flowers and it’s surprising how common they are. Occasionally they performed an aerial dance, circling around one another. Sometimes the males were more aggressive, hovering a few centimetres behind a feeding female, buzzing loudly and then pouncing, knocking the female off the flower. Given that the females have usually already mated, this behaviour is counter-productive and wastes valuable female foraging time. Perhaps the males are just hard-wired to behave in this manner as it ensures mating success.
…………………….

Female A plumipes 2
Female A.plumipes feeding from rosemary

 

By the third week of April I saw mostly the jet-black females, working hard, busily collecting for their nests, visiting a wide range of flowers. It takes each female about a day to provision one cell with pollen and nectar for the developing egg. Nests tend to be in sunny vertical surfaces such as cliffs, soil banks or holes in soft walls but although there are many old walls in Totnes with loose mortar I haven’t located a nest yet. John Walters wrote a nice description of A. plumipes nests in a soft cob wall near a Devon church. The cob wall offers good nesting conditions so the bees tend to nest in aggregations even though they are solitary bees.

The few males about looked faded and discoloured and noticeably slower than earlier in the season. They play an essential role in the survival of the species but they have mated with the females and are not needed anymore.

My last sighting of these bees was on May 15th. This seemed a little early and I can’t be sure if it reflected the lifetime of the bees or the bees foraging elsewhere. We won’t see the bees again for nine or ten months and the action now switches to the nests where eggs develop in to larvae eventually producing the new bees that will emerge next spring.

An experimental Bee House

Last year, I watched, fascinated, as Mason Bees (Osmia bicornis) made nests in tubes in a commercially produced Bug House situated in a local community garden, the Leechwell Garden. This Bug House is meant to be educational and so has been placed in a prominent position. This brings with it the risk that it will be subject to some attrition; indeed the removable tubes were tampered with both last summer and this spring and the Bug House was knocked off the wall twice during the winter.

I wanted to build another Bug House for the Leechwell Garden to be put in a less vulnerable place but it proved impossible to find a suitable position. I went ahead anyway and placed the new Bee House at the bottom of my garden which is about 100 metres from the Leechwell Garden (as the bee flies).

Experimental Bee House beginning of season
The Experimental Bee House at the beginning of the season (March 2015). I hope you can see the two vegetable boxes with the sides of the top one insulated with recycled vinyl floor covering, also the protective roof. Two cassettes with tubes are in place in the insulated top box . The garden still looks dormant although a few daffodils are visible.

 

My aim was that this experimental Bee House should be made from recycled materials so that it could be replicated by others at minimal cost. I looked around for suitable materials and one day as I was passing the Totnes shop of Riverford Organic, our local organic grower, I saw some vegetable boxes in the window. These looked ideal to make the body of the Bee House so I contacted them and they kindly gave me two boxes. The boxes were not fully sealed, needing insulation and rain protection, so I went to CarpetRight in Newton Abbot and they kindly gave me some samples of vinyl floor covering. I used these to insulate the sides of the new Bee House and to give it a roof. I found some logs, stones and bricks to provide ballast and stability as well as providing potential homes for insects. I sited the new Bee House so that it caught the early morning sun.

I wanted to provide tubes for the bees to nest in and had hoped to use inexpensive bamboo canes from the garden shop. Although I was able to cut up the canes, I found they were filled with soft material and unusable. I, therefore, had to buy solitary bee tubes from Wildlife World, my only outlay.

Experimental Bee House Cassette
One of the cassettes holding the bee tubes. The tubes are organised in to an old mineral water bottle and secured with a cable -tie. Four of the tubes contained mason bee nests from last year.

 

The tubes were organised in to cassettes. Each cassette was based on an old mineral water bottle cut down below its spout but long enough to protect the tubes. About 20 tubes were placed in to each cassette and these were secured using a cable-tie. I put out two cassettes in March, each containing four tubes with nests from last spring in order to give the new Bee House a start. A third cassette went out on May 28th when I thought the bees needed extra capacity but only two tubes were filled.

Experimental Bee House end of season
The end of season view. In two cassettes most of the tubes have been filled, in one cassette put out later two tubes were filled. Some tubes where the seal was broken have not been refilled.

After I had made the cassettes I read that plastic is a poor choice because it is not breathable but by that time it was too late to change design. Despite this, the new Bee House seemed to have functioned well and many of the tubes were filled by hard-working female bees during spring 2015. This is described in the previous post.

Successes and failures with this year’s Red Mason Bees

As we humans continue our lives and perhaps savour the prospect of settled warm weather and holidays, the busy part of the year is already over for the solitary Red Mason Bee (Osmia bicornis). These important pollinators began their activity in early spring and have now built their nests and laid their eggs.

Last year I was fascinated to watch some of these bees in a Bug House in the local community garden (The Leechwell Garden). This year I kept a closer eye on this colony to try to understand their behaviour. I also built an Experimental Bee House at the bottom of my South Devon garden and watched the bees build nests. [I realise not everyone is interested in constructing new bee houses so I have described this in the next post.]

This week is Pollinator Awareness Week so it is especially important that we think about how to protect and encourage these pollinating insects.

The males emerge and misbehave

male Osmia
Male Red Mason Bee

 

Both Bee houses contained mason bee nests (in removable tubes or in wooden blocks) constructed a year ago. The removable tube nests overwintered in my garden shed and were put out again on March 6; twenty four filled tubes and some empty ones went in the Leechwell Bug House and eight were put in the new Bee House. The wooden block nests stayed out all winter as they are an integral part of the Leechwell Bug House; they may have suffered damage when the Bug House was dislodged from the wall.

Osmia on Bug House
Male Red Mason Bee resting

 

I watched the tubes carefully from mid March and was very pleased to get the first hint that a male had emerged when, on April 16th, I noticed that one of the mud seals had been broken. The day before had been very warm so perhaps that encouraged the bees. Over the next week, I began to see males flying about near the two Bee Houses. Fresh males are very beautiful: about two thirds the size of a honeybee and with long antennae, they have vivid orange abdominal hairs, a fringe of beige hair around the thorax and a very distinctive pale “moustache”. Some look a bit different: they have few abdominal hairs and look rather shiny.

Osmia shiny type
Shiny type

 

Osmia feeding from Forget me Not
Male Red Mason Bee feeding on forget me nots

 

The numbers gradually increased over the next two weeks and on sunny days there would be a cloud of male bees near the Leechwell Bug House (perhaps as many as 30) behaving in a very characteristic way. They would fly about, swinging from side to side rather like a metronome, sometimes stopping to look in to a tube, sometimes flying off to feed on nectar. They would also “bomb” one another, especially another male that had stopped to rest or to warm up. I saw one male try to pull another out of a tube and, once his friend was out, he tried, rather unhelpfully, to mate. The cloud of bees would work themselves in to a frenzy when it was very sunny or when a male/female mating pair was present, perhaps they could they smell other females.

Osmia looking out
It’s too cold for me ……

 

All this activity would stop when the temperature fell to 11oC or lower. The males would retire to the tubes in the Bee House, sometimes two or more in one tube where they would look outwards waiting until the conditions improved. Other bees such as the Hairy Footed Flower Bee continued to forage at this temperature and the disparity may have something to do with size, the larger insect being able to tolerate the lower temperature.

Some females and some mating

mating pair April 28 15 2
Mating pair with mites

 

Mating pair with other bees May 7 15
The stillness of the mating pair and the frenzy of the other males.

 

I didn’t witness any females emerging from their nests but I knew that had happened when I saw mating pairs on April 28th and May 7th in the Leechwell Garden. This was an exciting moment as it was a first for me. I was amused to see the female in the first pair decide to go walkabout; the poor male had no option but to sit there even when dragged in to a hole smaller than comfortable for two bees. My excitement was tempered by noticing many mites on the first mating pair which I suspect is not good news for the bees. The latter mating pair did not have the mites as far as I could tell.

Males near the end

worn out bees

Some of the males continued to patrol the Bee houses up to a month after emerging, ever hopeful of finding a receptive female. By this time they were wizened and black and didn’t look like red mason bees any more apart from their white facial hairs. Perhaps we would also look sickly if we fed on sugar alone. They disappeared altogether by the end of May.

Hard working females

yellow pollen
The first pollen-loaded female.

 

May 12th was another exciting day as I saw chrome yellow pollen on the floor of the Bee House at the bottom of my garden for the first time: I now knew that the females were busy building nests. The females are also distinctive and very beautiful, about the same size as a honeybee and larger than the male with, on their head, two horns which they use for tamping down mud. They lack the pale “moustache” but like the males, their abdomen is clothed in vivid orange hairs when freshly emerged.

Female Osmia bicornis
Female red mason bee. The horns are just about visible.  Her colour has faded and a better view of a fresh female with her orange hair is seen in the mating pictures.

 

I watched the females returning after foraging, buzzing loudly and entering tubes head first. After a short time they reverse out, turn round and back in to the tube. I am not sure what is happening here but I witnessed the behaviour many times. Once this elaborate manoeuvre was complete they flew off for more. I also saw one female building a mud partition. She added mud to the inner surface of the tube and gradually, over several trips to collect mud, built the partition inwards keeping it symmetrical and circular before sealing it off.

Throughout the season, there seemed to be plenty of forage about and no shortage of mud for nest building. For both Bee Houses I saw females continuing to fill tubes in to the third week of June.

Problems

In both locations, the number of females seemed very low, especially as there were plenty of males. Last year most of the tubes and wooden block holes in the Leechwell Bug House were reused by females who cleaned out the mess before re-provisioning them. This year the females did reuse old tubes but seemed to prefer fresh tubes when available. In the Leechwell Bug House I saw only two females but they filled more than twenty tubes. Males emerged from the wooden block nests but none of these was reused. At the bottom of my garden there were at least four females and they filled twenty four tubes. In both locations, the mud seal on some of the tubes remained intact and neither males nor females appeared.

Osmia housekeeping
Housekeeping

 

End of season view
End of season for the tubes in the Leechwell Garden Bug House. Many are filled, a few have not been reused and a few have not been used at all.

 

I don’t know why this year has been less successful but I wonder if the tubes were tampered with at a critical time. I know that some were stolen last summer so I presume that, at that time, many of the tubes were disturbed. I also suspect that the tubes in the Leechwell Garden were tampered with again in March this year. Perhaps this double interference damaged the developing females. The Bug House also fell to the ground twice and perhaps the wooden block nests were damaged. Another possibility is that mated females were produced but decided to go elsewhere.

A third possible explanation would be that the old tubes had been infected with another organism that damaged the developing bees.

I opened up the wooden block nests to see if I could glean any information about these problems. None of these had been refilled this year, whereas last year they were all reused. The wooden blocks were very messy: I could see the individual cells made by the bees but there were no intact dead bees. The nests were filled with a brown dust although within this dust I could see dead larvae. It was also clear that in many cases the mud partitions between cells were still intact. There had clearly been a major problem with these nests and I suspect that they may have been infected. The bees avoided these nests so they seemed to know that something wasn’t right.

I am beginning to think that new tubes should be supplied each year to make life easier for the bees and to avoid build-up of contamination.

Now it’s important to leave this season’s nests so that the eggs can develop and grow in to larvae. I need to wait until late autumn before moving them.

Overview of the year

It’s been another fascinating season of Mason Bee watching and as before I have been enormously impressed by the hard work and ingenuity of these bees, especially the females. The males have only one purpose but they seem to do it well.

Watching these bees is not only a fascinating experience, it also makes you aware of the interconnectedness of the natural world. The bees depend on flowers and the flowers depend on bees. We mess with these relationships at our peril and perhaps we understand our own place in the world by realising this. The highlight of season for me was seeing the chrome yellow pollen for the first time. It signified that everything was working; females had mated and were visiting flowers to continue their species. Fresh yellow pollen has a colour like no other, it seems to glow with the energy of sunlight and signifies the unfolding spring.

More solitary bees – and their unsavoury friends

cineraria nest in CP April 13
Andrena cineraria nests

 

On a sunny day just over a month ago, I was watching the solitary bees (Andrena flavipes) in a soil bank by the edge of one of the town centre car parks. It was a mid-April Sunday, the car park almost empty, so I wandered along the bank to check for any other bees living there. I had looked before and found nothing but this time I was surprised to find freshly disturbed friable soil and some bees about the same size as honeybees but with prominent black and white hairs. I took as many photos as their behaviour would allow and when I looked at various bee resources I reckoned these were most likely Andrena cineraria, the Ashy Mining Bee. The name refers to the colour of the hairs on the thorax of the bees and cineraria comes from the Latin for ashes.

Ashy Mining Bee 4
Andrena cineraria, can’t say if it’s male or female.

 

The Ashy Mining Bee is a very pretty solitary bee, particularly the female with her distinctive black and white hairs; the males are not so clearly marked although they do have white facial hairs. My photos  don’t allow me to identify males or females with any certainty although I did see two bees that were either fighting or mating.  I have not seen any females with pollen and I don’t think this is a large accumulation of nests but it does show that there are two species of solitary bee living in this unassuming soil bank in a town centre car park adjacent to the Leechwell Garden.

Ashy Mining Bee poss male
A. cineraria, probably male

 

Ashy Mining Bee 2
A.cineraria, probably male

 

Ashy Mining Bee Mating Pair
Fighting or mating?

 

While I was watching these bees, another large insect about the size of a medium bumblebee appeared and patrolled the nest area. With its smart coat of russet hairs and its long proboscis clearly visible, this was a bee fly, most likely Bombylius major.  These are parasites of A. cineraria and flick their eggs in to the soil nests where they develop and take over.

Bee fly
Bee fly

 

Later, I also noticed a smaller insect with a prominent yellow banded abdomen. In the photograph it is digging in the soil upside down. This is probably a nomad bee but, from this photo, I cannot say which species. A few days later I saw two Nomada flying about; these could be Nomada lathburiana known to parasitise nests of A. cineraria by laying eggs which develop and kill the bee egg or early larva.

seen near cineraria nest
Nomad bee digging near A.cineraria nest

 

Nomad bees
Two nomad bees flying near the A.cineraria nest region, possibly Nomada lathburiana.