Both meteorological (March 1st) and astrological (March 20th) spring have come and gone, but we still haven’t got to consistently warm days, spring flowers and budding trees here in central Wisconsin. In fact heavy snow is predicted in the coming week. Urgh!!! The bees are still sticking close to their warm hives; only venturing out for cleansing flights in bright sunshine. However, I did see some bees returning with loaded pollen baskets last week. I hear that some beekeepers will be getting packages as early as April 7th. So we better be planning out our bee work NOW.
The first thing to making a plan is to look back and see how we can improve. March 31st marks the end of beekeeper’s winter. For beekeepers winter survival statistics are calculated over a period from October 1st to March 31st. Using this period gives everyone a common reference point. To my disappointment and despite following the same varroa mite treatment protocol as the previous two years my winter survival took a nosedive. Was the decline due to my beekeeping practices or maybe new diseases that I have recently become aware of; SMS and DWV3?
This past winter I ended up with a mediocre 51% survival and I suspect a few of those survivors may slowly dwindle away as frequently happens. So there is room for improvement. I guess I should be thankful that by splitting I should be able to replace most of my losses.
I keep a detailed spreadsheet about all overwintered hives. I record data about each hive and then try to draw some lessons from the results. Data such as queen type, queen age, hive strength, mite treatments, wrapped or unwrapped, cluster location are all entered in the data base. Here are a few of my observations.
1. Hives with Saskatraz queens had the highest survival rate at 100%. I only had 2 Saskatraz hives so this may not be a significant data point, but this line of bees has been bred over the last 20 years to coexist with varroa.
2. Hives with Purdue Ankle Biter queens had a survival rate of 73%.
3. Hives with Russian queens had a survival rate of 48%.
4. Local mutt queens had a survival rate of 67%.
5. For the second year in a row hives headed by package queens had 0%, yes ZERO percent, survival.
6. 2nd year queens had a slightly higher survival rate over 1st year queens. But this may have solely been the effect of the package queens. When the package queens are removed the 1st and 2nd year hive survival rates of 1st and 2nd year queens are the same within 1%.
7. As an experiment I did not treat two Russian hives with miticides. They had the same survival rate as the Russian hives I had treated.
I went through all my deadouts and to the best of my limited abilities determined the reason for each hive’s demise. I classed one as being robbed out in late fall. Five were classed as starvation. The remainder (75%) I classed as viral/bacterial die outs. Where do I go from here? Let’s look at each in turn.
a. The robbed out hive should have been combined with another hive earlier in the fall. Poor job on my part. I need to get better at detecting and combining weak hives.
b. I have not weighed or even just hefted hives in the fall to determine if they are underweight. I also deliberately chose to only fall feed 1st year hives. I had mistakenly assumed 2nd year or older hives would have sufficient honey stored away. That accounts for 4 of the 5 losses. I will make it a point to check all hives earlier in the fall and feed as necessary. One question I can’t answer was if the underweight hives had viral/bacterial infections that resulted in sick bees and therefore less foraging bees and less stored honey.
c. Viral and bacterial diseases are spread by varroa; so even the newly reported diseases can be curtailed by a good mite control strategy. In previous years I had treated with MAQS in mid-August followed up with top up treatments of oxalic acid in September and October with good success. I never confirmed the effectiveness of these treatments by doing mite checks. Trying to get an arm around the situation based on what I have read I will do the following. In April I will treat all hives with oxalic acid vapor; 3 treatments a week apart. I also will monitor a few hives using screened bottom boards throughout the summer to verify low mite levels. Finally, I will move in my fall MAQS treatment to early August. After pulling the honey supers in mid-August I will run mite checks on all hives to confirm the MAQS treatment was effective and varroa mites are below permissible levels. If not, I will treat again. The September and October oxalic vapor treatments will remain the same.
d. Now to the package queens. Simply put, I plan to replace all package queens on or before mid-June with mite resistant stock, such as, Saskatraz, Ankle Biters, or Mite Maulers.
Remember the 6Ps! Prior Planning Prevents Piss Poor Performance. So, I’ve done my prior planning. Now I just need to execute to plan and not let laziness get in the way.