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EmsE
30-03-2010, 08:23 AM
Morning Everyone,

I've managed to get my first lot of bees through their first winter (probably good luck rather than good management). I'm sure I read somewhere that it is a good idea to treat bees for Varroa in April- is this right? If so what type of treatment would you recommend?
I don't think they have a big problem with the mites but will send a floor scraping sample off to check(when the weather changes).

Thanks

EmsE:D

gavin
30-03-2010, 09:10 AM
Hi Ems

Excellent that your bees have made it through the winter, and nice to see you contributing. I think that treatment in April is really only needed when there is a problem. If your bees are on a mesh floor then it is easy to check the sheet underneath to see how many are dropping over a period. If not, then when you have drone brood you can use a drone fork to inspect a sample of drone pupae and the mites will be easily visible.

If you have a few per day dropping, or a small percentage of drone brood infested, then keep monitoring but you may be able to delay treating until the late summer. One favourite way of knocking them back in early summer is to put a shallow frame at each side of the brood nest as the colony is building up. If you already have little drone brood at the time and the bees are starting to feel prosperous, then they will probably make drone brood underneath the shallow super frames. The mites dive in just before sealing, and you cut it off with a hive tool and remove before they emerge.

Did you treat in the autumn or winter?

best wishes

Gavin

Neils
30-03-2010, 12:35 PM
This looks a good a place as any to join in.

I was wondering the same as I specifically DIDN'T treat with Oxalic Acid over the winter maybe I'm doing my bees a disservice but it seemed a very harsh treatment to me so I decided to do a spring apiguard course instead. I did treat fairly late september into october if memory serves correct with Apiguard as part of the winter prep which knocked down a huge number of mites compared to what I was expecting from the weekly monitored drop.

Being a little conscious of the time now I put an apiguard treatment on over the weekend on mine. I know it's a little cooler here (12-16 degrees during the day) that Vita recommend for Apiguard (15degrees) but as a 2-6 week treatment I wanted to get things moving before I end up trying to do everything at once on a single colony.

I double checked the Vita information regarding problems associated with cutting treatment short and there don't appear to be any so I could possibly stop after a single tray if the mite drop still appears low.

And yes, I'm aware a possible side effect is a reduction or cessation in the queen laying rate, but I didn't notice any effects in the autumn treatment and I'm keeping a close eye on this one.

gavin
30-03-2010, 08:18 PM
Hi Nellie

If your mite drop this week is low I'd blame the weather and try again once it really does warm up in April. The trouble with treatments at this time of year is that they do need time, and you wouldn't want them on while the bees were bringing in honey. I would imagine that the rape might be flowering in your neck of the woods in about three weeks? Not really enough time to do a full Apiguard treatment. Given that your colony has 4 frames of brood at the moment it could be filling the brood box by the time the rape comes into flower, and needing its first super.

If I was you I'd try the shallow frame trick. It will knock back the population if you do it well and probably allow them to get through to a late summer treatment. It also gives you a chance to fork out the drone brood (easiest when the brood is getting more mature) and get a clear idea of the load of mites they are carrying. You might have an option to treat in the June gap instead if your locals say there will be one, or hold off until the late summer after the main flow but before the autumn brood raising and maybe a balsam or ivy flow.

There was a Dutch website that suggested that the recovered drone pupae make a nice stir-fry!

I know that people say oxalic is hard on the bees, but then thymol fumes do clearly upset or annoy them. I don't think that there is a way to kill Varroa without affecting the bees somehow, short of letting them do it themselves (which, of course, very few can do).

best wishes

Gavin

EmsE
30-03-2010, 08:47 PM
I did 1 floor sample on the hive last year which contained several weeks worth of debris (I was just learning) The varroa count came back as Nil?? The last treatment I gave the bees was oxalic acid at the end of November but I didn't get the opportunity to check the mite fall.

So, Next step then is to establish the mite fall, then...
* If low (or dare I hope for, nil), leave them and try the short frame in the brood box
* if more than a couple a day then treat with.....

I do like the idea of encouraging the drone brood. Seems much kinder.

Gavin, I've just noticed your info on eating Drone pupae- ugg

gavin
30-03-2010, 09:00 PM
I do like the idea of encouraging the drone brood. Seems much kinder.


Not if you're a drone its not!

;)

A drawback of removing drone pupae is that unless there are other drones in the area then you may be making it more difficult to get queens mated.

A nil Varroa count is unusual. With that along with a winter oxalic treatment you should not need to treat for a while. They should get through to a late summer treatment in a healthy state, but it is worth keeping an eye on the levels by looking at floor samples (if under a mesh floor - on a solid floor they might clean up before you see them) or by forking out some drone brood occasionally.

best wishes

Gavin

gavin
30-03-2010, 09:10 PM
Jan Tempelman was the guy recommending eating drone pupae. Recipe at the foot of this page:

http://www.beedata.com/apis-uk/newsletters08/apis-uk0708.htm

Whilst Googling I stumbled across this amazing article. Plenty ideas there for bee gourmets!

http://www.fao.org/docrep/w0076E/w0076e19.htm

Jon
30-03-2010, 10:54 PM
As a vegetarian for 30+ years I can't possibly recommend eating drone pupae but I came across this Dutch research.

http://www.apiservices.com/articles/us/varroa_drone_method.htm


Varroa mites are most often found in drone brood. Capturing mites in drone brood is nothing new. In fact, it was the first method used to combat the mites. But since not all mites were captured and many survived in the worker brood, this method was relatively ineffective and other methods were employed.

Varroa mites propagate in brood cells. Research from the University of Wageningen (The Netherlands) has shown that the Varroa mites are 12 times more likely to enter drone cells versus worker cells. Therefore, If a situation is created wherein all of the mites are on the bees (and not in any brood) it is possible to catch a high percentage of the mites with a couple of drone cell brood frames. Capturing mites in broodless hives with drone cell frames is very effective. A broodless period is essential to this method since the mites, all on the bees, will be caught in the drone cells. This principle is used in biotechnical mite control methods.

Neils
31-03-2010, 01:45 AM
Hi Nellie

If your mite drop this week is low I'd blame the weather and try again once it really does warm up in April. The trouble with treatments at this time of year is that they do need time, and you wouldn't want them on while the bees were bringing in honey. I would imagine that the rape might be flowering in your neck of the woods in about three weeks? Not really enough time to do a full Apiguard treatment. Given that your colony has 4 frames of brood at the moment it could be filling the brood box by the time the rape comes into flower, and needing its first super.

If I was you I'd try the shallow frame trick. It will knock back the population if you do it well and probably allow them to get through to a late summer treatment. It also gives you a chance to fork out the drone brood (easiest when the brood is getting more mature) and get a clear idea of the load of mites they are carrying. You might have an option to treat in the June gap instead if your locals say there will be one, or hold off until the late summer after the main flow but before the autumn brood raising and maybe a balsam or ivy flow.

There was a Dutch website that suggested that the recovered drone pupae make a nice stir-fry!

I know that people say oxalic is hard on the bees, but then thymol fumes do clearly upset or annoy them. I don't think that there is a way to kill Varroa without affecting the bees somehow, short of letting them do it themselves (which, of course, very few can do).

best wishes

Gavin

On the plus side, in the middle of Bristol we don't get much OSR ;) the downside, from my point of view, at the moment is that my "drone comb" is currently full of stores so I daren't even knock it off to let them draw it out at the moment. It will have to go at some point as they drew out worker comb rather than drone comb anyway, catching it at a point where it's low on stores and not full of brood is one of this season's challenges I think.

I will admit to a degree of trepidation publicly admitting that I didn't treat with OA and that I slapped Apiguard on so early in the season, but I did my best to make an informed decision. In an ideal world I wouldn't use apiguard either, but as a single colony beekeeper at the moment, that's a big risk to take especially as it looks like both the other colonies in the apiary at best will need to be combined if we're to have more than one colony between us over the next couple of weeks.

I know bees don't like Thymol much and that I'm risking stopping the queen laying at a fairly crucial point but at the moment I don't trust the mite counts that I saw last year (or my maths, one of the two) and I've agonised over whether not treating with OA was the right thing to do. That said, if the forecast doesn't improve I'm quite happy to run up in between showers and take it off again if it doesn't look like much good is being done and fall back to drone culling; something else I don't really want to do if I can help it as my gut feeling (i.e. I've absolutely no evidence to back it up) is that the combination of trying to reduce the number of drones being raised to begin with AND then culling them as part of varroa IPM can't be a good thing.

Nasty little barstewards aren't they? Leave them alone they almost certainly kill your bees and everything else you can do is trying to judge which is the lesser evil you can inflict on them this week. I'm going to stand by my decision though, it's a 4-6 week treatment and by the end of that time I want to be agonising over whether they should be drawing out supers or the 14x12 frames I want to move the artificial swarm onto. I've got 8 drawn super frames, 30 of foundation in varying stages of construction plus all the 14x12s AND I want at least a pot of honey this year ;)

gavin
31-03-2010, 09:29 AM
Hi Nellie

Yup, they're unpleasant critters.

Even if the Apiguard isn't working properly it is probably not doing much harm so there is no need to take it off. Low temperatures may make it ineffective, but if so it is likely that the low evaporation means that the queen can ignore it.

You can remove a first cycle of drone raising then let them complete it next time.

Do you have good queens in the two colonies you want to combine? Starvation risk is probably nearly over and the spring build-up underway. If I had two small colonies with good queens I'd just leave them alone for now. I hesitate to combine queen-less or drone laying queen colonies with good ones as there is a risk you'd lose the good queen.

best wishes

Gavin

Neils
31-03-2010, 11:08 AM
The short answer to the other two is no they don't. They technically both belong to other guy I work with. 1 is colony with a lot of chalkbrood throughout last season, the other is our "entertaining" swarm colony from last year that was still superseding queens into september. That being said, it made it through winter so maybe we should give them some credit. I've not inspected either so I'm only going on word of mouth but I understand both colonies were down to around two to three seams of bees a couple of weeks back.

Considering the relative strength of mine going into winter I'm kind of surprised that it's come through as strong as it has. Despite the chalkbrood the other colony was on brood and half, and needing it, so it's a shame to see it come through so badly.

I guess I should append to the "What I learned in my first year" post "Keep good records", I didn't last year which is perhaps why I was a little hasty to slap Apiguard on. I know I treated last year and I know I was surprised by the mite drop during the treatment compared to what I thought I should see as a result of the weekly drop but that's as much information as I could tell you so I was hoping to start this year with a clean slate knowing that the Varroa Levels should be low (and I'm keeping better records this time around).

EmsE
31-03-2010, 03:40 PM
I guess I should append to the "What I learned in my first year" post "Keep good records", I didn't last year which is perhaps why I was a little hasty to slap Apiguard on. .

I found good record keeping is harder than I thought it would be. I find that I keep getting lost with what I have or haven't noted. Then one of the children (though they won't admit it) wiped my file off the computer. Thankfully my mentor has been keeping notes on my hive too. This year I've promised to try harder with this and to do regular floor scrapings. Off to a good start so far:cool:

GRIZZLY
31-03-2010, 07:14 PM
Keeping records is easy-peasy,all you have to do is keep 2 record cards per colony. One card you keep under the roof in a sealed freezer bag and the other you keep in your equipment box.ALWAYS fill in the one in the hive first EVERY time you visit the hive ,then if you can't remember what you did/saw or lose the card in the equipment box,a quick check under the roof will reveal all.Keep the records simple and don't forget to date each entry.

IanT
05-04-2010, 09:46 PM
Hi there,

Has anyone tried dusting with icing sugar? Not having mesh floors I'm a bit stuck on knowing what the reduction in the drop rate was when I tried it last summer. But I'm told it fair causes the little mites to drop off, also saw in Thorne's catalogue (p50) a a few ways for applying icing sugar ( I just used a fine sieve). It seems a particularly good method to use over the summer as there are not any nasty chemicals to get in the honey. Any advice on the efficacy would be much appreciated - I do use Apistan in the autumn as well.

IanT

gavin
06-04-2010, 08:23 AM
Hi Ian

I have tinkered with it but not as a main method of controlling Varroa.

Icing sugar does knock mites off bees but I wouldn't rely on it being effective enough to hold the mite population in check. Many mites will be inside sealed cells, so you have to keep doing it repeatedly to catch those that have just emerged before they infect new cells. Also if you don't have a mesh floor they might be able to crawl back up onto passing bees.

If you miss half of them then the population may be back at its previous level after a week or so, especially if there is drone brood as they multiply faster in that (14 days sealing to opening, mites can produce four daughters in that time).

Before I had mesh floors I usually kept an eye on mite numbers by looking at drone brood. You can guess what proportion you sampled and multiply up the number to estimate the total in the colony.

Apistan also isn't guaranteed to work well now. The large-scale beekeepers in my area seem to have resistant mites, and I stopped using it years ago. Apistan will probably knock down mites in every hive, but what matters is the numbers you have left. If it only got half of them it isn't much help.

Many beekeepers are using one of the other methods that can kill most of the mites (98-99%) during the gaps between honey production. Oxalic acid in the winter, thymol in the spring or summer, for example.

best wishes

Gavin

Neils
06-04-2010, 03:43 PM
Hi there,

Has anyone tried dusting with icing sugar? Not having mesh floors I'm a bit stuck on knowing what the reduction in the drop rate was when I tried it last summer. But I'm told it fair causes the little mites to drop off, also saw in Thorne's catalogue (p50) a a few ways for applying icing sugar ( I just used a fine sieve). It seems a particularly good method to use over the summer as there are not any nasty chemicals to get in the honey. Any advice on the efficacy would be much appreciated - I do use Apistan in the autumn as well.

IanT

I do use Icing sugar, but very much as a part of the whole, so to speak. Getting a definitive answer on how well, if at all, Icing sugar works as part of Varroa IPM seems very difficult, I've seen articles claiming that it's briliiant and articles claiming it makes no difference whatsoever and everything in between. My own view is that it probably helps but I certainly don't think that as treatment goes it's on a par with Apiguard et al in terms of efficacy.

I take a very technical approach to my application of Icing sugar. I take a British Standard handful and apply forward momentum in the direction of the top of the frames, any that remains on the frame tops I brush onto the bees.

beeanne
09-04-2010, 12:25 PM
I use an old spice jar (the little Sharwood glass ones with a plastic seive-y thing on top) to dust mine. Adding a couple of grains of (uncooked!) rice helps stop it from getting lumpy.
Like Nellie, I've found some articles swear its brilliant, others say it's pointless, others say it's actively a Bad Thing, hassling the bees for no good reason. Personally, I do it at the end of an inspection, so the bees have already had to suffer my hassling them and I don't think it really adds more stress to them.

Neils
12-04-2010, 07:45 PM
Well that was an interesting trip up to the allotment. I ended up being later than I'd anticipated so the wait for a full inspection goes on, while the sun was still shining, it was a little windy and blowing a little chilly for me to want to take everything apart for a leisurely look around.

My apiguard treatment has been, how shall we say? Interesting. I know the temps have been a little low, but after two and a bit weeks I'd have expected a few more than the 3-4 mites I found on the floor this evening. While the overnight temps have been as low as 2-3 degrees over the past couple of weeks it's been pretty dry during the day, the bees have been active and temps have been up around 12-16 degrees for the most part yet the mite drop was negligable.

With the bees now covering 9 frames and the allotment plots around threatening to burst into flower any day I've decided to Super rather than continue the Apiguard.

I'm not going to read too much into it for now and I've left the floor in for another couple of days to see what, if anything changes as I'm hoping to go up again tomorrow and carry out a first full inspection.

EmsE
14-04-2010, 12:40 PM
I think I read somewhere that using the icing sugar technique supposedly encourages the bees to clean themselves more therefore making it harder for the varroa to stay on the bee:confused: If I had one of those things on me I wouldn't need icing sugar to encourage me to get rid of it so I can't say I'm convinced with that theory.

I got my Varroa results back today from a 2 week sample I sent to the SASA which says that no varroa mites were present:D.

I've got the super frame in the brood box, and the bees are doing a great job already in drawing it out.

Neils
14-04-2010, 12:49 PM
I think I read somewhere that using the icing sugar technique supposedly encourages the bees to clean themselves more therefore making it harder for the varroa to stay on the bee:confused: If I had one of those things on me I wouldn't need icing sugar to encourage me to get rid of it so I can't say I'm convinced with that theory.


I think I'm right in saying that it's supposed to have another effect too. in addition to encouraging the bees to groom the Varroa mite is supposed to have sticky feet and the icing sugar supposedly makes it harder for them to get a grip and hang on by covering their feet in dust so the two in combination help by making it easier for the grooming to knock the mites off the bees.

EmsE
14-04-2010, 02:22 PM
....the Varroa mite is supposed to have sticky feet and the icing sugar supposedly makes it harder for them to get a grip and hang on by covering their feet in dust.....
I'm more convinced by that.