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I visited my out apiary over the weekend and found that one of my colonies, colony ummm, has died. Colony Ummm? Unfortunately I need to cross check my records to work out which one has died. I really ought to keep better records

The cause appears to be insufficient strength going into winter. The dead bees remaining in the hive were only enough to form a cluster about 10cm diameter, split across 4 sides of frame. When the cold started they couldn't move to neighbouring frames to access the stores there. I had left a super on top with stores which weren't touched. I had also left in the Queen excluder, which probably didn't help. At the top of the super was a wasp body, suggesting that there had been some robbing before winter killed the wasps.

The dead bee bodies were soft, so I think that they had died very recently. Maybe some were alive, but in a way which prevented them being saved. I shut the lid.

I removed the super indoors, and moved the hive around the corner. When the weather is warm enough I hope that the other bees will rob it out without causing a robbing storm.

Update: after reviewing the list of colonies I think that it was colony 18

I was called back to the site where I'd collected Colony 20 on Friday (3rd July 2020). I eventually made it there on Sunday. Life is busy.

There was still a small cluster of bees at the top of the tree. The most likely explanation is that the Queen is in that cluster. The bees rest of the swarm (in the hive) is busy making comb. No pollen is coming in.

The Queen is too high up for me to reach. If she's still alive today (7th July 2020) then it can't be for much longer.

I will have to do something with Colony 20 because they appear to be queenless.

I was called to the Barton Fields allotments to see a swarm of bees on a bush. By the time I arrived it had fallen onto the ground. I placed a box next to it and gently scooped some bees into it. Quite quickly there was fanning and the remainder marched in. The whole catch must have taken no more than half an hour.

I gently cycled home with the box on my bike. It turned out that the box was slightly damaged so a couple of dozen bees escaped. I left them in a cool place and marched them into a hive the next morning.

I was called on 24th June to see a swarm in 2 parts on a tree. The tree was on raised land next to the canal towpath in Jericho, Oxford. There was no hives nearby so I suppose it came from the Cripley Meadow Allotments which are reasonably nearby.

The swarm had formed in 2 places in the tree. By the time I saw it, it had joined into one fair sized swarm at the whippy top of the tree and was in accessible. Next morning it had fallen out of the tree and was all over the ground.

I put a box over the apparent centre of the swarm but the behaviour was very disorganised -- bees were fanning in different directions and moving very slowly to gather. There was also an area where bees were clustering about 2.5m away. I tried lifting them into the box but they wouldn't cluster properly. There were bees fanning but it wasn't having much of an effect. The bees which did go into the box coated the inside, rather than forming a lump.

After some mucking about I decided to leave the box with them to see if they'd get organised. I had lunch, had a nap, returned about 3 hours later. They were mostly in the box but there were still some on the outside. This was partly because I was using a box with vents. Ventilation is good once the bees are in the box but they often cling to the outside of the vents, attracted by the smell of the queen.

Eventually I got enough bees into a box to take them away. I tried to walk them into the hive during the hot afternoon but they stayed in the box. Again there was fanning in more than one direction. I left the box propped up against the hive entrance. Next morning they were still in the box. Hive lid off. Bang bang. Bees in the hive. It's a catch.

Even though most of the bees stayed in the box there was activity in the hive. I found evidence of comb building. This points to a possible explanation: this is a cast swarm with more than one unmated queen. Virgin queens have less strong aroma, which would explain the slow and disorganised responses of the bees. Multiple queens would explain why they formed 2 groups before I arrived, on the ground, and when I tried to hive them.

I inspect my hives by looking at what comes out of them. At the front this means bees. Underneath, on the base board, this means wax; pests; pollen; Propolis; crystallized honey and bits of dead bee. Everything which comes out tells a story about what goes on inside.

Dark wax and dry Propolis

Wax cells within the area where the Queen lays eggs will be lined with Propolis. This darkens the wax. When the brood hatch out they chew threw the cap of their cell, causing dark wax to fall out of the hive. When a nurse bee comes to prepare the cell she may also drop Propolis fragments and . The chewed cappings are larger and fairly evenly distributed; the residue from brood cell clean up is more like dust and tends to pile up.

The location of this wax tells you where brood rearing is going on and roughly how many new bees are emerging.

Light coloured wax and shiny new wax platelets

All new comb is white. The bees make wax platelets from their abdomen which they pass up to their mandibles (mouth parts) to chew. The chewed new wax is then applied to build the comb. Some of these platelets get dropped from the hive. They sparkle in the light and appear very white.

Where comb has been damaged, or it is being remodelled, there may be chewed wax which is very light in colour.

Light coloured wax domes

Drone brood, the only male bees in the hive, are larger. Their brood cells are correspondingly large and are capped with a dome of wax. They chew around the edge rather than through the top, so the entire dome falls to the base of the hive.

Drone hatching is a good sign that swarming season is underway.

Mix of wax colours with Wax Moth Larvae droppings

Wax Moth lay their eggs on comb. Their larvae prefer the edge of brood comb where there is honey, stored pollen and propolised brood cells. The larvae eat their way through brood comb in straight lines. A mix of wax colours drops out of the hive, along with the larvae droppings (ie poo) which look like short black sticks.

It is not unusual for Wax Moth to live inside an active hive. Vigorous colonies with good habits remove the larvae when they can. This can be a useful sign that a swarm has occupied a new hive. The colony will immediately start to clean up the comb and eject wax moth larvae. The smaller larvae fall through the Varroa screen onto the base board.

Crystallized honey

Honey is a combination of water, Fructose sugar, Glucose sugar and a few other important chemicals. When the proportion of Glucose is high relative to Fructose the honey will crystallize more quickly. Crystallization is also temperature dependent, happening less readily at hive temperatures. The crystallised honey is not suitable for the bees to eat so they sometimes remove it from storage comb. It falls out of the hive as very white crystals which are sweet to taste.

Pests

The pests which I normally find are either Wax Moth larvae or Varroa. I have written quite a bit about Varroa previously, and mentioned Wax Moth above.

Bee Parts

Sometimes there are bits of bee on the base board. I can't be sure what grisly fate befell these bees but I can guess. In spring these are probably bees which were trying to get into the hive through the Varroa screen. They can't get in so they stay trapped on the wrong side. They may be fed by other bees through the mesh but if it gets cold they will die. Ideally the screen and base board should be sealed to prevent this.

Later in the season there will be wasps. These eat bees. I think that they bite and pull at the legs of bees through the screen (although I haven't seen it happen). They also attack bees inside the hive if they get in through the door. I have in the past found many legs. It's horrible and the wasps are relentless.

Pollen

Bees bring pollen into the hive in their leg baskets. These form the pollen into a kidney shaped lump. The pollen is a food which they eat to produce the high protein brood food and Royal Jelly. When these lumps of pollen are dropped they drop onto the base board. They can show which plants are flowering. Pollen also indicates that the bees are producing food for brood or storing it in anticipation.

All my hives appear to be alive at the start of April. There is humming in all the hives. There are bees flying and pollen on most of the removable base boards. This is great news. We've had turbulent weather since last summer -- high winds on many occasions; heavy rain through the autumn; persistent damp cold. Now spring is well underway and there are flowers and blossom.

This is still a tricky time. Spring build up can leave a colony starving. Late cold or windy weather can make colonies vulnerable. The colonies have more brood and so a greater need for heat. If they're low on stores they can starve in even a short period of cold weather. The hives are lighter too, because they have less honey in them, so they are vulnerable to high winds.

I hope that the point of greatest danger has passed.

Hot on the heels of Storm Ciara comes Storm Dennis. The UK experienced strong winds and very heavy localised rain. There has been flooding in some areas, but not in Oxford yet.

Looking at local wind speed and wind gust speed, Storm Ciara looks about the same strength as Storm Dennis. Gusts around Headington up to 30 knots; gusts around RAF Brize Norton around 45 knots. There was steady rain for most of the weekend.

Thankfully my hives have stayed upright. Nothing much to report. I just wish that the rest of the country could say the same.

There's a lot of weather around. Last weekend brought Storm Ciara to the UK. Next weekend we'll get Storm Dennis.

There were fence panels down in our garden and a tree has blown down within sight of the house. The forecast was indicating gusts up to 66mph (57kn). It was noisy indoors.

Ciara seemed much stronger than usual, but how does it compare?

I have data for several weather stations going back to the start of 2017 (source: MetOffice WoW). My preferred weather stations are RAF Benson and RAF Brize Norton because they seem most likely to produce reliable results. Air fields tend to be in flatter, more exposed places so the wind gusts are probably as high as they'll be for that region. Urban wind patterns, and those for a valley like Oxford, may be lower. Unfortunately I don't have data for central Oxford and my urban data series (Headington, Bicester) are not continuous for the same period.

For comparison (values > 40 in bold):

In terms of the absolute gust strength storm Ciara doesn't look much bigger than Feb 2017 or March 2019.

I've been visiting the hives in central Oxford every couple of weeks. There is still evidence of activity on the base board in all 6 hives (chewed cappings; dead Varroa; etc). I believe that they're all still alive and ok.

There are causes for concern though. All the hives have visible numbers of dead bees at their entrances. I don't know whether these were healthy bees which were stranded during cold weather or whether they were virus infected bees which crawled out of the hive. I presume the latter.

Four of the six hives have significant stores. Two are rather light and probably wouldn't last until spring unless I intervene.

Today I caught two swarms. It must be the weather.

Helen from my bee group is on holiday so I caught a very large swarm from one of her hives. It was tricky to catch. The swarm had settled around the trunk of a tree which had lots of stiff little branches. It was a little over 2m up.

Shaking the swarm at all was difficult. I upset the bees so much that I had to walk away for a while. Bees are supposed to lose interest if you walk under a tree. Not these bees. I swatted away with the low hanging branch of an Ash tree but they weren't having it. I was stung and then I found a couple of bees had found their way into my veil. I had to kill them. This was not my best work.

Somehow the shaking got the Queen into the box. From there I propped the box near the tree and let them sort it out. Five hours after the catch the tree had been deserted and most of the bees were in the box. They weren't happy when I sealed them in.

Top tip: use a box which opens on its shortest sides. If you try to seal a cardboard box along its longest side it may open and allow a few bees out. I can see them outside the window now. I hope they find their way home.

The second swarm couldn't have been simpler. I was offered a ladder when I arrived. I banged the swarm into a box from its branch in an apple tree. I let them settle a bit. I could see fanning. I could also see a lot of waggle dancing which I think meant that they were discussing a nest site. I shut the box sooner to end that conversation. Done.

This swarm was from the site in Barton where I've caught several swarms before. They are from a feral colony which lives in a capped chimney. The colony has been there since at least 2016. Sadly my 3 colonies from this source all died in spring 2018 during the very cold spring weather.

One of our bee group took both swarms. I hope they thrive in rural Oxfordshire.

My bee group talks about the 'June gap'. This is is the period where the spring flowers end and forage becomes scarce.

Many of the bee group are in rural areas of Oxfordshire where Oil Seed Rape is the primary crop. There are gardens and some hedgerows left, but their pickings are slim. In the city this is mostly not the case.

In central Oxford there are numerous gardens which are planted to bloom throughout the summer. There are the many rivers where the Elder has been flowering through June and the Iris (Flag) has been blooming. These areas are prone to flooding and so are less likely to be built on or put to single-use agriculture. The city must be beautiful if you're a bee.

All the gardens and green spaces won't completely compensate for the end of the blossom on the big trees like Horse Chestnut. The evidence on the base board of my city hives shows this. The lumps of pollen which drop off the bees' legs are much smaller -- perhaps half the diameter of the lumps which fall in peak time. There is a greater variation in colour at this time -- bright oranges; occasional deep reds; a purple and even blue.

There are lots of flights too. This indicates that there's something to do. I don't know whether they're returning full of nectar or with just enough to make it worth the trip. They might be bringing water or propolis. Whichever it is they're busy.

As June wears on I see that the Blackberry is in flower. This provides good forage for a while. The pale grey pollen is already dominating the base board. The plants grow prolifically around Oxford. Their seeds are distributed by birds and the plants will suffer any soil type. They'll flower during June and some of July and produce fruit during August and into September. With the arrival of the Blackberry flowers I call an end to any June gap.

It has been raining, windy and cold this week. From Monday 10th June to Thursday 13th June the number of flying hours may have only been 12 hours out of a possible 66 hours*. The constrain on flying hours is only hours above a minimum temperature:

The rain and wind would have been additional constraints.

On Thursday lunchtime I went to check on the bees. I was concerned that Colony 17 might be starving. While I was there a swarm was pointed out to me. It was clinging to a tree about 6m up.

The weather had been so poor that they must have swarmed on Sunday or early on Monday. There were small mounds of bees on the floor looking very cold and wet. There were very few flying bees.

After some thought I decided to catch them. I reasoned that they had probably used up the honey in their stomachs. In this starved state there was a low probability that they'd be able to find a new nest site, occupy it and forage enough to survive. Stuck on a tree in the rain they might fall and cause a hazard for passing pedestrians.

On Friday morning I called the Oxford University Parks department. They were great. They arranged a team with a cherry-picker to come out. I really appreciate their help.

Once there I went up; shook the branch twice to get the bees into the box; and came down again. The catch couldn't have taken more than 5 minutes once the cherry picker was in place.

I had a hive ready. It had some comb from a previous colony. I also put in a tub of thick (but not fully set) honey. I tipped the bees into the top of the hive. There was no prospect of them walking in. I then did something unusual. I completely shut them in. It was a lock-in.

This morning I checked on them. They had moved up onto the comb. I removed the honey and opened their door. We'll see how they fare.

* Flying hours assume that the minimum temperature for flying bees is at least 13C when measured in Headington. The Headington weather station is a little over 4.5km away from my out-apiary site. The climate in Headington is noticeably warmer than in the valley where my out-apiary is sited. This apparent temperature difference is caused by humidity from the river. I do not have the data to support exact number of flying hours at a particular hive.

A quick check under the Varroa screen of Colony 17 showed that the bees are building comb. There were shiny wax platelets in a shower where under where they've clustered. There is also evidence that they're cleaning out other parts of the hive. I found 2 dead wax moth larvae and some other detritus.

It's still too soon to see whether they do have a Queen in there. I tried the 'knock test' -- to see whether they remain agitated after a knock on the side of the hive -- but it was inconclusive.

I don't usually feed my colonies. I'm especially cautious about feeding swarms because they arrive with honey which can contain spores from a variety of diseases including the devastating American Foulbrood. The usual advice is to leave the bees alone for a week. They will build comb and use up the honey which they arrive with.

When I put Colony 17 into their Commercial hive body I had too few full-sized frames. I increased the number by putting in shallow frames from a super. Yesterday I quickly opened the hive to replace the shallow frames with full-sized deep frames.

It was quite cold yesterday, with the temperature only briefly climbing above 13C. The colony was clustered in one corner; there were very few flying bees; there was no sign of comb building. Had they run out of stores? There is still forage around -- the wild roses are in bloom and the Elder -- but we are approaching the 'June Gap'.

I decided to feed them with sugar. They discovered it very quickly. I hope that it will replenish their energy so that they can forage when conditions improve. I don't like feeding because it may disrupt the normal behaviour of the bees. On this occasion I've relented.

I was called by Mary, a member of my group. She had caught a swarm from her top-bar hive in Headington. She kindly offered me the swarm, knowing how much I value untreated colonies.

The swarm is from a colony which Mary has kept, untreated, for about 2 years in a Top Bar Hive. Before that they came from a feral swarm somewhere near Steeple Aston in Oxfordshire.

I took the swarm down to central Oxford in the early morning and walked them in. They went in very willingly. The swarm was a reasonable size. I didn't see the Queen going in.

They seemed agitated in their box. Every movement causing them to buzz loudly. This might be a sign that they are not Queen-right (ie they have lost their Queen). A knock on the hive wall is the usual way to test whether they have their Queen. They'll buzz but calm down quickly if they do have a queen. I think that they'll need to be left for at least a week before I do that test.

On Sunday I harvested two supers of honey from Colony 1. They had filled three supers during the spring and had started building comb on top of the crown board.

Harvesting is fairly straightforward now. Cut; spin; strain; put into containers. Easy.

At the edge of one of the supers there was some louvred comb. This is where the bees cross-comb at the edge, reorienting their comb in a direction which looks like it's part of a circle. I cut this out. It's one of the downsides of comb without foundation. Over time I'm building up straight comb to put back into the hives so this happens less.

I also successfully extracted the foundationless comb without any damage to the comb: spin slowing on each side. Then a second spin on each side to get the remainder.