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Will a hive that has a mite count of 70 do better than a hive with only one mite? Will the hive with fewer mites be the only one to survive the winter?

I'll know the answers to these questions next spring.

After turning my hives into gas chambers with formic acid, I did a mite count to determine the current levels of infestation. Droogie 1, always the over-achiever, had one mite on its sticky board after 24 hours. Droogie 2, however, had 70. I think the difference is due to the number of boxes on each hive when I treated them. Droogie 1 only had two medium hive bodies, while Droogie 2 had three medium hive bodies. I think the formic acid may not have been sufficiently concentrated to be effective in Droogie 2 due to the increased volume of the hive.

So I'm encouraged by the numbers in Droogie 1, have learned an important lesson (only treat with two mediums on the hive) and will be able to see how the bees do with the rainy season and cooler temperatures now upon us.

This brings my first amazing season of beekeeping to a close. Wintertime is good for ordering and assembling new beekeeping supplies, and I plan to take advantage of a rainy weekend to make candles with the wax Ellie and I have in our freezer left over from the honey harvest. I'll definitely post some pictures when we've made them.

How 'bout them mites?

It's been quite a while since I've posted anything about my bees, but lately I haven't been seeing much of them. That's because I decided to treat them with formic acid for the mite problem and the treatment requires them to be undisturbed for three weeks. I was very fortunate to get some pads for free from a beekeeper who shares the beeyard. He also let me borrow the extra woodenware that is needed to place the pads on top of the hive. Thanks!

So they've been treated and I removed the formic acid pads last Friday. I'm going to do a mite count this week to see how it worked. When I visited them today, there was lots of activity at the entrance of each hive, more activity than the neighboring hives, which leads me to believe they are doing well.

Results

Powdered sugar is great. For donuts. Not so much for bees.

After a month of diligently dusting the bees every 3-4 days, I was finally able to measure the mite loads on Friday.

The results are not good: 100 per day for Droogie 1, 60 per day for Droogie 2. This huge increase in mites from the numbers that I counted in September is despite having fewer bees in each hive.

Here is a close-up picture of the sticky board that I put under the hive to do the mite count. I've put an arrow by several of the mites; many more are not marked.


This makes me sad. I haven't decided if I'll treat the bees or not- there is a small chance that they will survive the winter if I do nothing. But I'll probably order some formic acid pads and see if I can save them.

Yikes! Mites!

One of the problems with factory farming is that it allows pests to build up and easily transfer from one host to another. Something similar might be happening with my bees. I think that having so many hives in our Stanford bee yard may contribute to a big problem with Varroa mites.

Varroa mites attach to bees as they develop and feed on the larva. This can prevent the bee from developing properly and they also carry viruses that can destroy a hive. Here are some pictures of the mites.

Scott Bauer, USDA Agricultural Research Service, www.forestryimages.org

I did a mite count last week to determine if there are any Varroa mites in the hive, and if so, how many. The way that I do this is to put a sticky sheet of paper under the screen that serves as the floor of the hive. Occasionally, the mites will fall off of the bees and through the screen at the bottom of the hive, thus getting trapped on the sticky paper. At the end of a few days I retrieved the paper and counted the number of mites. Here are the counts:

Droogie 1: 186 mites /4 days = 47 mites/day average

Droogie 2: 35 mites /4 days = 9 mites/day average


Bad news! The levels that a hive can tolerate would be around 2-3 mites falling per day. I doubt that my colonies will be able to survive the winter with this level of infestation. After seeing this shocking number of mites in my hives, I now understand why the neighboring hives don't usually survive the winter. He uses Italian bees, which are much more susceptible to mites than my Russian strain.

So what do I do now? I really, really don't want to use any pesticides in the hive. That said, when I'm surrounded by other hives that aren't well taken care of and are mite-infested, it is almost certain that my hives will succumb to this pest.

I've decided to try an organic approach first, and measure the mite loads after I've finished. If I cannot bring the levels down, I'll try using formic acid, which has been proven to work and supposedly doesn't leave a residue behind.

The organic approach that I will take is to dust the bees with powdered sugar. Once they are covered with sugar, bees then groom each other to remove the powdered sugar and remove mites in the process. It sounds reasonable. However, there aren't any studies that show that it is effective. Based on what I've read, I have decided to dust the bees with powdered sugar 2X per week for three weeks, and will do another mite count at that time.