We are finally getting a little bee friendly weather. The bees have been busy bringing in tree pollen with which to raise brood. Also been seeing a little clear nectar. But the late snow storms in April have really set back the normal hive buildup. While inspecting hives in the last week of April I have noticed two things. In general, bee populations in overwintered hives are significantly lower than last year. Last year the hives were fully occupying both brood chamber boxes by this time. This year, the bees were only in the top box of most overwintered hives. Slightly better, but not by much, than newly installed packages. Dandelions also made a late appearance on April 27th. It appears we are about 3 weeks behind what is normal for central Wisconsin.
As a beekeeper who raises queens I also need to monitor the hives for the presence of drones. So far this year I have not seen any drones although I have seen a few capped drone cells. Currently the bees are putting all available resources into raising worker brood. Based on these observations I doubt conditions at this time will result in May swarming. June swarming is an entirely different kettle of fish. To get swarming requires high bee populations, drones, queen cells and a strong honey flow; none of which are present right now.
This year I am trying to improve my mite control process. As part of this I have installed screened bottom boards on two overwintered hives in order to closely monitor mite populations. About two weeks prior to installing the screened bottom boards I treated the two hives twice with oxalic acid vapor. Two days after installing the screened bottom boards I checked the witness boards and both hives had dropped 2 mites each. After 2 more days I checked again and there were 7 and 3 mites on the bottom boards. I will be using a mite drop threshold of 10 mite in a week as the trigger to do a mite treatment. Curiosity getting the better of me I checked again after 2 more days. This time there were 0 and 4 mites. Both hives are now tied at a 9 mite drop after 6 days or 1 ½ per day. It appears that the 2 oxalic acid vapor treatments did not eliminate the mites in these two hives. I will be following up with more treatments and mite counts in May and also comparing the effectiveness of oxalic vapor versus an oxalic alcohol treatment.
Based on the mite drop noted above it is possible to roughly estimate the mite population in those two hives. Based on the 1 ½ mite drop per day there are approximately 300 mites in each of those two hives. Consulting with Randy Oliver’s varroa mite model it appears that these two hives will definitely be in the danger zone by August. Therefore, I will be treating for mites on all overwintered hives prior to mid-May. I will probably be using a ½ dose of MAQS or FormicPro.
Last week (April 26th) I got my courage up and did my first queen graft for the year. The first night the newly grafted queen cells spent the night in my basement since overnight temperatures were down in the upper 20’s. As of May 1st I had 17 capped queen cells. There still is a 3 week wait for the queens to emerge and mate.
Our replacement packages finally arrived on April 30th. So I spent today installing them.
Tasks to be done in May are:
-Split extremely strong hives
-Check the new package hives after about one week to ensure the queens are released, accepted and laying
-Continue feeding new package hives 1:1 syrup until the bees stop taking it or the frames in both brood chambers are fully drawn with wax
-Consider adding a 2nd brood chamber to the new package hives if the queen has laid eggs in the center 6 frames
-Treat for mites in all overwintered hives about mid-May
-After the mite treatment is a good time to install the first honey super. There is always the chance of a big nectar flow from locust trees. Use or not use a queen excluder according to your preference.