Oxford Bees

Colony 05

Hive H is stable after move

Submitted by will on Tue, 29/08/2017 - 22:09
a simple wasp guard made from pieces of National brood frames.

Hive H has settled in and has brood and stores.

It absconded in early August. I returned the colony to the same hive and then moved it to Headington. I put the frames to the front of the hive; fed them with Honey and made a very small entrance. This has encouraged them to produce brood and defend their entrance. I've seen lots of wasps around but none appear to have got in.

The neighbouring hive - Hive B - has absconded or failed. I suspect robbing. Both hives are very near an apple tree which attracts wasps. The return of Hive H to health suggests that they are now willing to defend against wasp attacks.

Hive B is empty

Submitted by will on Tue, 29/08/2017 - 21:27

The colony in Hive B has failed or absconded. The hive is now completely empty.

The colony has always been small. In a year they built only 5 frames of comb (on National deep frames). I thought that maybe the effort of being at height had over-stressed them so I moved the colony from the out apiary to my back garden. I placed them under an apple tree in the hope that they would recover. There is good forage and they were at ground level.

I had seen some coming and going at the hive entrance in recent weeks. It all looked like normal activity. I saw no wasps going in or out. The entrance was partially concealed by apple tree leaves so I thought the colony was ok. I didn't open it.

The position under the apple tree may have encouraged robbing by wasps which I hadn't noticed. The colony may have lost its' Queen. It may even have been the move which killed her - although I was gentle.

Whatever the cause, I noticed unusual activity at the hive entrance yesterday. I checked the removable base board and saw a large amount of sugar on it - clear evidence that there was robbing of crystallised honey. Today I opened the hive and found it utterly empty: no bees; no Queen; no brood; no stores. I have no idea where the Queen and the other bees went.

What effect does Varroa have on roof top colonies?

Submitted by will on Thu, 25/05/2017 - 07:36

Two out of the three established colonies in my roof top apiary are big and vigorous. Meanwhile Hive B has stayed small since it was caught as a swarm a year ago. Why?

I've been told that some colonies are smaller than others. The bees like it that way. I'm willing to trust the bees to right-size their colony but I'd like to understand what causes the differences. I wonder whether Varroa and its diseases might be an explanation.

Since moving Hive B back home to ground level I have seen evidence of comb building in Hive B. This is co-incident with a nectar flow so I'd expect there to be some increase in storage space. I have also noticed an increase in the defensiveness and a high rate of Varroa mite drop on the hive floor, relative the colony size.

Varroa suck the bee's hemolyph whilst they are pupating in their brood cells and later while the mites cling on adult bees. The hemolyph is bee blood. Removing it weakens the bee, as well as transmitting viruses. My suspicion is that this colony in Hive B has a low resistance to the mite and is being progressively weakened by their action. Bees returning to roof top hives from ground level will have to ascend over 20 metres whilst carrying a full load of nectar. If the weaker bees were being lost this would limit the number of foragers. Younger bees would be promoted to foragers which limits the number of nurse bees available to care for brood. This would give a mechanism which explains why this colony, which superseded last year and are apparently happy with their Queen, haven't built up.

I will be watching whether Hive B builds up strongly at ground level and continues to shed significant numbers of mites. This would strengthen my suspicion that they lack the resistance to mite attack demonstrated in Hives C and D.

Moving hives

Submitted by will on Sat, 13/05/2017 - 11:06

Last night I moved Hive E to my out-apiary and returned Hive B to my home. The move went well with no problems.

Hive E contains the feral swarm from Barton caught at the very start of August 2016. It built up strongly before Autumn and is now a vigorous colony. I wanted it to be in central Oxford where its' strength is a match for the position - lots of forage but a big climb to the roof. I wanted Hive B to be in my garden where it can quietly tick along without bothering family or neighbours.

There are dangers in moving an occupied hive:

  • The colony can overheat in transit, causing the comb to soften and collapse. I read that this usually kills the colony.
  • The frames can slap together, damaging brood and bees.
  • A substantial bump can cause bees to fall to the floor, blocking the ventilation and causing the colony to overheat.
  • A bump to side of the hive can cause the boxes to slide and open up, releasing alarmed bees.

None of the above happened during my move.

It's usual when transporting bees to exchange the crown board and roof for a ventilated screen. I don't have one so I secured the hive together with straps and lifted it into the back of a car. I opened the windows and cruised down the hill.

My out apiary is on the roof of a building with an automatic door. It doesn't stay open for long enough for me to get the hive out of the car and inside the building. I had to put the hive down gently whilst I opened the door. I may have looked rather comical trying to get back in time. Last time I dropped an empty hive on the ground. Once, but not twice.

Up went the hive and into its' place. I opened the door and a few bees came out and milled around.

I then packaged up Hive B and did the same in reverse.

This morning I looked in through the door of both hives. The hive floor was clear in both, indicating that the comb had not collapsed. I think that all the visible bees were moving. I peered into Hive E using a strong torch while the sliding screen was out. The inside of the hive must have been cool because the bees were clustered as if in a swarm. They were beautiful.

April build up

Submitted by will on Sat, 08/04/2017 - 13:07

I visited the out-apiary today and opened the 3 hives there. There is evidence of brood, new comb and stores in all of them. There's evidence of a nectar flow, which isn't much of a surprise given that Oxford is swathed in spring blossoms.

Hive B is still relatively small but ticking along nicely. There are plenty of stores and reasonable coverage of brood. I haven't added space because there are empty frames in the brood area.

Hive C was busy and rather aggressive last year. They seem calmer now, but a couple of bees tried to sting my gloves. I over-wintered them with a National deep and a super box. This was partly because they hadn't built comb into the deep and partly because there was brood in both. They've definitely built comb into the deep box now.

Hive D produced so much brood last year that I wondered whether they would starve for lack of stores. I even caved and fed them at the end of the season. A fair number of bees died of unknown causes and were littered outside the hive. This hasn't stopped them. There are a lot of flying bees and they've nearly filled a super in 3 weeks.

I added a super without comb, separated by an excluder to Hives C and D. Hopefully that will keep them busy for a while.

Wax Moth

Submitted by admin on Sat, 25/03/2017 - 12:08

Hive B has a wax moth problem - or they're unusually good at coping with it. I'm betting that it's a problem. I'll know when it's warm enough to have a look inside.

I have found 4 wax moth larvae on the removable floor of the hive. I've been keeping the floor clear of debris so I don't think they hatched on the floor, unless there is more debris that I can't see.

My expectation is that this colony is tolerant of wax moth. That's not a good thing. This colony is small and has superseded at least once. It hasn't shown any characteristics which are obviously good from my point of view. I'm not going to destroy it but I wouldn't be sad if the hive became available during swarming season.

 

Knock down update - no visible problems in either hive

Submitted by will on Wed, 01/03/2017 - 10:47

I've been keeping an eye on the two hives which were blown over during Storm Doris.

Neither is showing any significant visible sign of damage:

  • There were no dead bees on the floor of the hive (as far as I could see).
  • The fall of wax cappings appears to be the normal.
  • Hive D had some drops of honey on the removeable hive floor, but only just enough for me to taste (yum)

I'll see in a couple of months how these hives have fared. I'm still seeking data on the peak wind speed.

Hefting Data

Submitted by will on Thu, 09/02/2017 - 13:52

I returned today to the out-apiary and hefted all 3 hives there.

I used a digital scale to weigh each side. The reading varied considerably during each heft - maybe by as much as 250g each way. I did my best to get an average reading. I think the variability must have been due to the way I was using the scale.

The results show more or less what I expected:

Hive Name Hive Type Left side Right side
B National deep box with insulated eke 8.9 Kg 15.2 Kg
C National box with 2 national super boxes >25 Kg >25 Kg
D Commercial box with 1 national super box and insulated eke 17.8 Kg 16.6 Kg
Hefting weights for hives in Kg

The weight of each type of hive, given for shipping information by Thorne, is:

National + 2 supers 25 Kg
Commercial + 2 supers 27 Kg

My conclusion from this is much as I expected: Hive B is small and may not have enough stores for the spring. Hive C has tons of stores and is fine. Hive D may have enough and needs monitoring.

I checked the varroa floors. All hives are consuming stores as expected. Hives C and D are making new wax, shown by wax scales amongst the capping detritus. Also C and D had a couple of Varroa each, which is quite a high fall rate.

Bees flying in February (out apiary)

Submitted by will on Tue, 07/02/2017 - 14:52

It's a warm day today (10C-12C). The bees are flying from all 3 hives in my out apiary. Presumably they're going on purging flights. I didn't see enough activity to rule out pollen collection but it seems unlikely.

I keep the removable floor in, so I was able to see tidy mounds of chewed cappings. There were some flakes of fresh wax amongst it in hives C and D, suggesting that there has been some brood rearing. I didn't establish how much, nor whether it's going on now.

There were a few stranded bees outside hive C. They'd grabbed the bright yellow hive strap and then become too chilled to move. I moved the strap so that it was out of sight. There was no way to save the stranded bees. There were quite a few dead bees outside the front of hive D. It's a bit more worrying because the undertaker bees usually dump the bodies away from the hive. I removed the floors and looked up at the Varroa screens. There were no dead bees on the screens, showing that the undertaker service is still working within the hives.

It's a good sign that all the hives have flying bees, but it's not a guarantee that they'll survive the winter. Spring is a time of expansion. They need stores for brood. If there isn't forage, or they can't get it because of cold then they can starve. Foolishly I forgot to heft.

Hefting

Submitted by will on Sun, 25/12/2016 - 21:54

I tried hefting a couple of days ago in my out-apiary. I haven't felt it was necessary before. Hives C and D seem well supplied. Hive B is rather light, but it was always a smaller colony.

A bee got cross when I hefted hive D. It tried to attack me but was whisked away by the strong wind of Storm Barbara. Windy.

Hive A is unlikely to need any hefting as it's massive. I haven't tried Hive E, but I ought to. It's the most likely to be in need of help.