Oxford Bees


A swarm, a rainstorm and a complicated start for Colony 18

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:

date site day length 10C or more 11C or more 12C or more 13C or more 14C or more 15C or more
2019-06-09 Headington 16.6 hours 14.5 hours 14.3 hours 14.0 hours 12.8 hours 11.3 hours 10.0 hours
2019-06-10 Headington 16.6 hours 8.5 hours 6.8 hours 2.8 hours 2.2 hours 1.0 hours 0.0 hours
2019-06-11 Headington 16.6 hours 9.8 hours 0.8 hours 0.0 hours 0.0 hours 0.0 hours 0.0 hours
2019-06-12 Headington 16.6 hours 14.3 hours 12.3 hours 9.0 hours 6.2 hours 3.5 hours 0.0 hours
2019-06-13 Headington 16.6 hours 15.5 hours 12.8 hours 8.8 hours 3.5 hours 0.0 hours 0.0 hours
2019-06-14 Headington 16.6 hours 16.3 hours 16.3 hours 13.8 hours 10.8 hours 10.0 hours 8.3 hours

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.

Colony 17 building comb

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.


Feeding Colony 17

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.

Colony 17 arrives

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.

June Harvest

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.

The first Wasp

I saw the first worker wasp of the season. She was hovering near Colony 1.

Earlier this season we saw a lot of Queen wasps. This suggests that it may be a waspy year. There have also been lots of aphids for the wasps to feed on. Wasps require mostly protein early in the seasons which they use to feed their brood. They switch increasingly to needing sugar during the season, which is why they try to rob honey bee colonies.

I have annual problems with wasps. These are most noticeable in central Oxford. I've seen wasps trying to rob my hives at dawn (6am), at dusk (10pm) and all through the day. This continual onslaught would destroy a weak colony so I stop down the doorways to a space about 9mm by 25mm. Even so the wasps still get in and may even be attacking the bees through the Varroa screen under the hive. It's brutal.

Three full supers on Colony 1

Colony 1 has been very busy. I opened the top today to find three full supers. The bees were even building above the crown board and would very soon have run out of space.

I lifted off two of the three supers and put two new ones in their place. Then I put a Canadian Clearer Board and replaced the two full ones on top. In a day or two there will be an early harvest.

We had a taste of the fresh honey from on top of the crown board. It had a light colour and subtle aroma which probably indicates Horse Chestnut. The taste had the intensity which only fresh honey can deliver.

Crawling bees and signs of Deformed Wing Virus prevalent across hives

Colony 1 has been continuously occupied for over 6 years. Every spring, except 2018, there have been bees crawling around outside the hive -- stricken with Deformed Wing Virus or some other paralysing virus. These bees became food for Sparrows.

This year seems worse than previous years. There appear to be more bees crawling and for longer. This might not be worse than usual but it feels it. In April it was mostly Drones which were crawling around. Now it is more likely to be workers.

Last season had a very cold spring. Four out of seven colonies died from starvation or isolation starvation (ie there were too few bees to reach the few stores that were left). There was a definite brood break which will have reduced the number of Varroa and may have been the reason that there were very few crawling bees that season. Observing crawling bees is confused by the Sparrows eating them. I think that in 2018 there was very little Sparrow activity.

This season there have been warmer temperature. I can't say for sure whether there was a brood break. There have been higher than expected levels of Varroa this season which suggests that any brood break that did happen had a limited effect on Varroa numbers.

All this points to higher stress in the established hives this season. Conventional wisdom would suggest that there will be colony failures. Perhaps this will happen. I would expect that this would be seen as colonies succumbing to robbing by wasps or other colonies if it does. We'll see what happens.

Honeydew falling from the Lime Trees

The Lime tree (Tilia Cordata, or the Linden tree) is found all around Oxford. As I cycle under the avenue of them on South Parks Road I can feel the slight prickle of honeydew falling.

Honeydew is a sugar-water liquid secreted by the aphids who live on the Lime trees. They suck the sap and excrete the liquid which falls in a light spray from the trees. The leaves quickly get a shine where large amounts of this liquid has dried on them. I've seen this in other places around Oxford.

Honeydew can be forage for bees. They collect it when there are fewer nectar sources. The flavour of the honey is said to be distinctive -- "very dark brown in colour, with a rich fragrance of stewed fruit or fig jam" (source: Wikipedia). Hopefully there will be some to collect from my city hives this season

Colonies 15 and 16 getting settled

I took a quick look at the stuff which has been falling out of Colonies 15 and 16 today.

The removable tray under Colony 15 had lots of new wax platelets, indicating that they're busy building comb. There were also at least 3 Varroa bodies. This shouldn't be a surprise. Varroa are in all the colonies which I've encountered. This period after swarming has no brood so all the Varroa in the hive are clinging to the bees. Every mite which dies now does so before it can infest a brood cell, which is good news.

While Colony 15 had very little comb in their hive, Colony 16 had lots. Much of this was brood comb from a previous colony. It was beginning to suffer from wax moth and was heavily propolised (brood cells are lined with propolis). After only 16 hours were was a thick mess of dropped comb on the removable tray. There were half a dozen wax moth larvae in various stages of development -- a vigorous swarm doesn't tolerate them. The detritus was so thick that I couldn't tell whether there were any Varroa. I'll have another look in a day or two.

One method of detecting Varroa mites amongst a thick layer of muck is to use Methylated Spirits (a mix of Methanoic and Ethanoic alcohol). This separates the mites from the muck, making them easier to see.

edit 25/05/2019: the flight patterns of colony 16 appeared to be the increasing circles which indicate orientation flights. It's hard to be certain. Individual bees are hard to see -- they are small and dark; they move quickly across a patterned background and there are lots of them.

Welcome to Colony 16

I received a call at lunchtime today that there was a swarm settled in Portland Rd, Summertown, Oxford. I went immediately.

The swarm was big. It was in the lower branches of an apple tree where it hung over a fence. I borrowed a ladder and just knocked the bulk of the swarm into the box and waited while they got organised. In went the remainder. Boxed.

Collecting could hardly have been quicker or easier. From phone call to me leaving with a box of bees was only just over an hour. Quick work given that I must have taken 30 minutes just to get there.

I was very grateful for the kind assistance of the neighbour Chris and to the home owner who gave us access. They were superb. This sort of help fantastic -- freely and kindly given -- and much appreciated.

I took the bees back to central Oxford where I left them, boxed, to calm down. At about 8:45pm I tipped them onto a sheet in front of the hive. The movement was immediate. In they started to go.

After a while the door became jammed with bees. More bees climbed up over the entrance and onto the front of the hive. It was a bit chaotic. The evening is still warm though so I hope they'll get organised before it cools down too much.

Arrival of colony 15

Yesterday I collected a swarm in a box which originated in Tackley, near Bicester, Oxfordshire. The swarm was collected by Paul from Oxford Natural Beekeeping group.

Paul believes that it is a prime swarm and that it comes from an established feral colony. This is great news; I believe that feral colonies have adaptations which make them ideal for low intervention beekeeping.

I was unable to hive the swarm last night but they were safe in their ventilated box. They stayed outside at my out apiary over night. This morning I was up early and watching the temperature rise at my local amateur weather station in Headington. The temperature eventually crawled above 9C and I got to work.

I spread a thin cotton towel in front of the hive, tucking it in between the lander board and the entrance. I then opened the travel box and gently poured out the bees onto the towel. Member of my group recommend the walk-in method of hiving bees. I usuall favour using the big opening at the top of the hive instead (ie take the lid off and tip them in). Today I felt like trying it their way.

Walking in is more theatrical and it does ensure that they've willingly gone into the hive. I recently lost a swarm which I tipped in. I think that they would have absconded anyway but getting them to choose the hive might have improved the chances of success.

The bees on the towel started to climb upwards. This led them to the door. Some went in; then more. Within 10 minutes there was a crush at the entrance to the hive. I kept an eye out for the Queen and for workers fanning to indicated her location. Eventually, after at least half of the workers were crowding the door, I saw her. She crawled up and around the crush and disappeared in through the door. A little while later there was a bit of fanning, but not much.

I left for work and returned at lunchtime. The colony was now getting organised. There was busy traffic at the door and the crush at the door had cleared. There were very few dead workers left on the towel, which recommends Paul's ventilated box (he uses wire mesh taped to the inside of a cardboard box). On the removable base board there were signs that the bees had been cleaning up -- fragments of comb and propolised cell linings cleaned up from the previous occupants. Also they were building -- there were platelets of new wax on the base board. The wax is especially encouraging because it suggests that they will make their home in the hive.

Catching and Losing Colony 14

Yesterday I went to catch a swarm in Summertown, Oxford. The swarm was hanging from guttering above a first floor window.

The person who called me helpfully had a large ladder. After quite a bit of work we fixed it to the house and I approached the swarm. I was not delighted with the place that the swarm had chosen. When you are balanced 5 metres above ground on a porch roof it's best not to think about the ground.

The bottom half of the swarm was easy to catch. A quick swipe and they fell into the box. The remainder were in and around the guttering. Some were covering the roof tiles. Some were in the gap formed by the tiles where they overshoot the eaves and between the fascia and the guttering. There were lots of places to lose the Queen. Was she in the box already? I didn't know and I couldn't see any bees fanning pheromone which would have shown that she was there.

I gave the bees a few minutes to regroup. The bees in the box stayed there. The bees around the guttering stayed there. I had another couple of tries. Then I climbed down and sealed the box.

The couple who called me out were lovely and offered Tea.

I took the box of bees to my city apiary. At dusk I came back and poured them into the hive.

Today I returned to inspect them. The hive was empty.

It's not unusual for a colony to abscond. It can happen because they have found somewhere better; because they don't like where they've been put; or because they haven't been moved far enough away from their original nest. Any of these could be true for these bees.

As for whether I captured the Queen, I'm still unsure.

Supers for city centre colonies

I added Supers to all 3 of the colonies in my city centre apiary yesterday. I also removed the straw filled ekes which hopefully provide insulation on the roof of the hives.

The season feels well underway.

Accidental Queen inclusion in Colony 12

When I added a super to Colony 12 yesterday I discovered a problem -- presumably another one of my mistakes.

Last season I fed them and left an extra super on the hive over winter. I put it above a Queen excluder. Yesterday I opened the hive to put another super on and found that there were Drones above the excluder. Somehow the Queen had made her way into the super before I put it together.in

I moved the excluder above last the super which I put in last year. That will allow the Drones to hatch and move down through the hive. It'll take a while for the colony to sort itself out now. She has presumably been restricted for space.

I'm wondering whether I can encourage the Queen to move down to the brood box. Even if I do there will be Drones which need to be removed from the super later on. It's a mini-mess.

Very high Varroa count for city centre hives

I did a 24 hour Varroa drop count yesterday. This involves clearing the removable hive floor and counting the Varroa mites which drop out of the hive over a 24 hour period.

I counted

  • 15 Varroa on the floor of Colony 12;
  • 16 Varroa on the floor of Colony 4;
  • 30 Varroa on the floor of Colony 8.

These are very high numbers of mites for this time of year.

The modelling referenced by the National Bee Unit suggests that colonies starting the year with this many mites will be overwhelmed during the season. I'm not going to treat. I'll see what happens.

I did try to insulate 2 of these 3 hives before winter. The uninsulated hive had 16 mites. There isn't a noticeable difference in mite numbers between insulated and uninsulated which is counter-intuitive -- warmer internal hive temperature should encourage brood rearing which should give opportunities for mites to breed. This is a very small sample but I'm not seeing that correlation here.