Varroa Control - Drone Frame

As part of my varroa control strategy, if you can call it that, I inserted a drone frame into the brood chamber of my main hive, hive two. Drone take ~24 days to mature before emerging from the cell so the varroa are attracted to them. The extra 3 days increases the chances of another of the mother varroa's progeny reaching breeding age.

It wasn't fully capped but I didn't want the drone emerging and unleashing a flood of varroa on the hive. After removal I pulled 20 larvae and counted the mites on them. From this small sample I estimate that 1.5% of the drone brood where maturing while sharing a cell with a varroa mite family.

20 Drones, 3 female varroa

The chickens enjoyed eating the brood. Its not great for the bees because the chickens break the cells down so they have to be redrawn but I know none of the drones or their parasites survived.

The photo below shows a mother varroa mite and her male offspring. The male usually remain in the cell and have a very soft body. I'm guessing they don't like the sun either. This one is making a dash for the shadow on the tip of my thumb, under the larva.

My plan from here, once the new queen has begun laying, is to reinsert the drone frame and give the bees a month or so to repair the damage the chickens have done. By this stage there should be another frame of sacrificial victims so remove. I'll perform the same count and see how the numbers compare. I also need to put a sticky board under the hive and see what the natural mite fall is.

Hive Two - Second Inspection and some plans

Hive two now consists of 2 full depth, one .75 and a queen excluder. Its too big for my small yard now and I now have two young boys running around in the garden so the chances of bees getting squashed by them is increasing. They don't like being stung either...

I still want to try my hand at breeding a quantity of queens but I plan to use the top bar hive for that. The top bar hive still isn't populated. I did have it populated but they died out over winter. More on this in a later post...

There is a community garden just a few blocks away from where I live. They sound keen to have a hive there so I plan to move hive two onto their land. Because it is so close normally I'd have to move the bees twice. Once to a temporary location more than 5km away and then move them to their final location a few weeks later. This is because the bees are extremely good at navigating but forget to check where home is when they leave so if I move the hive a short distance the bees will take off in the morning, recognise the area they are in and so return to the old site.

To overcome this I plan to do the following

1. Breed a new queen in hive two
2. When the queen is almost ready to hatch move the current queen and some workers into the Top Bar Hive. If I do a graft today they should be almost capped next weekend (7.5 days) so next Sunday might be the time to make the move. Taking that into account, I won't do the graft today.
3. At the same time move Hive two aside and place the Top Bar Hive in its place
4. Move Hive two to its new location, about 1km away.

This should mean that any of Hive two's field bees that return to the old location will find their way into the Top Bar Hive, boosting its population. Any new field bees, heading out on their first flight, will orientate themselves based on the new location and return there.

In preparation for this I have located Hive two's queen and isolated her to the bottom box. I've also placed my queen rearing frame into the hive so that the bees can prepare it for a graft.

The hive is brimming with bees, every frame was reasonably well covered in bees, right out to the side walls. I weighed the top box (the .75) as I thought it would be interesting to see how quickly its weight increases. It is currently 16kg. This includes all the bees in the box at the time, 9 frames, a couple of frames of almost capped nectar and the remainder brood.

I've yet to see any significant varroa activity this season. I inserted a drone frame during the last inpection and it is almost all drawn out now. There was some brood in it but its not capped yet. Drone take about 14 days from capping to emerge so I want to remove the frame some time in the next two weeks. I spotted one worker with a mite on its back but otherwise all seems good. I still have put a sticky board in the mesh to see what the mite drop is, I really should get on to that.

Varroa Infestation

I've previously treated one of my hives for varroa with Apistan because I found a couple of varroa in the hive after doing a 24 hour survey. It probably wasn't strictly needed but I did it anyway.

I now have a full infestation that will need treating as soon as I have taken my honey supers off. This photo is the result of opening 3 drone cells. There are at least 6 mites in this photo. I had shivers down my spine as I watched one mite climb onto the back of a bee. The bee could obviously feel it as it desperately scratched at its back, trying to knock the mite off. The mite disappear into the gap between the abdomen and thorax. To make matters worse I had heard that a bee having a mite on its back is comparable to a human having a large rat attached to them and sucking their blood. Makes me feel for the bees as they seem to be completely unable to do anything about it and the mites can move very fast. To get an idea of the scale have a look at the photo on the right. The worker bee to the right of the queen has a mite just under her right wing.

Spotting the mites is quite easy. I found, once I knew what I was looking for, that I could pick a mite on the back of a bee, on a frame will of bees, with no problem at all. I suppose that once you 'have your eye in' for what is normal, the abnormallity of the mite sticks out like a sore thumb.

One of the most common techniques is to open a drone cell and have a look for the mites there. The mites prefer drones as they take a few days longer than the workers to mature. These few extra days give the mites a little longer to breed, resulting in one or two extra mites per brood cell.

Many people use a capping scratcher but I've found just busting up the drone cells with my hive tool to be sufficient. A healthy pupae is quite white so the mites are obvious. This drone pupae has two mites clearly visible on it. You can see that I have just removed a patch of drone cells.

Next month, as funds allow, I plan to buy some drone frames and use the technique described in this study (and this one) to see if I can knock the mite population back to a managable level. I suspect I'll still have to resort to Apistan, or something similar, to ensure the colonies health throughout winter.

The most encouraging part of this study is stated in the abstract.
"These data demonstrate that drone brood removal can
serve as a valuable component in an integrated pest management program for V. destructor and may
reduce the need for other treatments on a colony-by-colony basis."