[Olyviewbees]

Located in Western Washington
A couple guys in our group are reporting puzzling mite drops. We usually see hives in our area being bloodless around this time of year. They are treating with OAV and using sticky boards for mite count drop. They have done 3 rounds spaced about 5 or so days apart, and still 40 to 60 mites being dropped.
I have heard OAV is in the upper 90s effective this time of year.
What are we missing? Not bloodless, bad oxalic acid?

Highly doubt mite bombs with the weather we have had, wet, cold (Washington weather)

Looking for suggestions

 

[BecunaBees]

Burley (between Port Orchard and Gig Harbor). I am susbcribed. I am experiencing the same thing. Am on third treatment. Second dropped 200 mites. I was zero on alcohol washes in October. See what I have tomorrow after the third but three hours in I had 3-5 mites in some hives on bottom boards. 8 hives here.

 

[fatshark]

If you're definitely getting a significant drop when you treat it's likely that the OA is OK. Little to go wrong with it. Are you sure your vaporiser is functioning properly?

My bet would be that there's brood present. If you add a clean tray do you see characteristic stripes of biscuit-coloured cappings?

 

[Mike Gillmore]

What were the temperatures when you treated?

 

[beemandan]

What were the drops like following the initial treatment?

 

[Olyviewbees]

Temps are always over 45 and bees are flying day of treatment

 

[Olyviewbees]

Avg mite drops per treatment 82, 114, 44

 

[Olyviewbees]

Good idea. Will have them check

 

[ffrtsaxk]

The only reasons I have seen OAV treatments with results like that are: 1. not broodless (happens more often than most people think this time of year) 2. vapor did not rise up into the cluster (with low air temperatures the vapor will sometimes stay low and leak out around my screened bottom boards).

 

[Robert Holcombe]

7 strong foraging hives, 1 resurrected hive and a hive from a nuc, along with a great foraging year plus apparent "Varroa Bombs" in the area made it difficult to "clean out" all hives this Fall. What was really apparent from collected Varroa dead-drop data was the differences between the hives. One hive took 8 treatments over 2 months to get the dead-drop count down below 30, another barely broke 100 dead-drop count and looked very resistant, 3231 vs 450 total dead-drop count. Most hives were "cleaned" with 4 Fall treatments but it took 10 treatments for one hive. This year it was easy to identify the invasion point but not easy to reduce Varroa dead drop to single digits for all hives. A lot of work. One more treatment, Jan 6th, to verify 2X - 14 days apart winter treatment plan effects.

They're a lot of variables but I would guess hive size plus Fall winter brood rearing coupled horizontal Varroa migration extended the problem.

When in a Varroa Bomb period with winter brood I try to treat 4-5 days apart to prevent immediate invasion of larva. Wish I could stop them, Varroa, at the entrance. The reward for reducing Fall - Winter Varroa count to single digits is no need to treat again until next Fall, two years in a row.

 

[Olyviewbees]

It's been mild here so far the winter. So I am strongly suspicious that we are not totally bloodless like previous years.
I think the hardest thing is to figure out a way to make neighboring beekeepers take mites seriously.

 

[crofter]

I have seen mention that an individual colonies inclination to rob can make them prone to running high mite counts. If your colonies had quite uniform genetics mite count variation could be different than when a person had colonies with great variation in habits. Could this possibly be a factor in some people being more successful treatment free?

 

[dudelt]

I am just across the water from you and while it was cold for a few days around Christmas, the average temperatures for December have been way above normal. In fact, until Christmas eve, not a single day in the month had average temperatures at or below normal. My guess is that the warmer than usual temperatures have kept the bees brooding. For the first time in 3 years, I have lost hives to mites as well. Others in the Puget Sound area are reporting the same thing you are. Look for the post by Paulmon in this forum titled RIP Little Bees from 12/27/19.

 

[Olyviewbees]

I think my neighbors genetics have alot to,do with things. Even if I had the best resistant bees my neighbors mite bombs would overtake any hive. Just listed to a podcast that mentioned just that. Well managed hive podcast. It's new and so far great.

 

[trishbookworm]

Oh I'm going to get that one soon. I've caught up with the rest of the bee podcasts I subscribe too. My take on neighbor's hives being a source of mites: I plan for it. If they are willing, I will go to their apiary with my OAV wand (for 2-4 hives) and do OAV for them. I will also expect an infusion of mites in the fall from failing hives - theirs or others'. I know there is a guy across the way who has 2 colonies just... there. He doesn't inspect or take honey, let alone open them. Between my 13 hives with screened bottom boards, and my neighbors (who treats) with 4 hives with screened bottom boards, we got at least 12000 mites coming into our colonies. Not all of mine had such high drops (after low alc wash readings in late summer). Drops in October post OAV ranged from 40 to 2000 mites on the bottom board, with everything in between. Some of my girls are robby!!!! So, I just plan for it, and I find if I catch the robbing early, by treating with OAV frequently in the fall, then I will be safe.

 

[mamm7215]

I am just across the water from you and while it was cold for a few days around Christmas, the average temperatures for December have been way above normal. In fact, until Christmas eve, not a single day in the month had average temperatures at or below normal. My guess is that the warmer than usual temperatures have kept the bees brooding. For the first time in 3 years, I have lost hives to mites as well. Others in the Puget Sound area are reporting the same thing you are. Look for the post by Paulmon in this forum titled RIP Little Bees from 12/27/19.

Same here, I’m just north of you in Surrey Canada. Just finished my 11th oav and it looks like I may now be mite free. No drops last 4 days. 1 hive but neighbors have bees. I’m starting to think like others here that warmer temps may have kept brood longer.

 

[Fivej]

Oh I'm going to get that one soon. I've caught up with the rest of the bee podcasts I subscribe too. My take on neighbor's hives being a source of mites: I plan for it. If they are willing, I will go to their apiary with my OAV wand (for 2-4 hives) and do OAV for them. I will also expect an infusion of mites in the fall from failing hives - theirs or others'. I know there is a guy across the way who has 2 colonies just... there. He doesn't inspect or take honey, let alone open them. Between my 13 hives with screened bottom boards, and my neighbors (who treats) with 4 hives with screened bottom boards, we got at least 12000 mites coming into our colonies. Not all of mine had such high drops (after low alc wash readings in late summer). Drops in October post OAV ranged from 40 to 2000 mites on the bottom board, with everything in between. Some of my girls are robby!!!! So, I just plan for it, and I find if I catch the robbing early, by treating with OAV frequently in the fall, then I will be safe.

You might be better off buying neighbors robber screens. J

 

[BecunaBees]

Ok some data. I treated my hives on the following dates. Of note I did not count bottom boards after first (12/15) treatment because I forgot to clean before hand and didn’t notice till the next day. I will put the date and mite drops counted off of bottom board.

12/15/19 No data, just treatment.
12/22/19 A-200, B-50, C-10, D-10, E-30, F-30
12/28/19 A-152, B-51, C-10, D-12, E-11, F-30
1/1/20 A-21, B-62, C-6, D-2, E-14, F-35

I use a Kelly Wand with MannLake Oxalic Acid, just purchased prior to these treatments. Fall alcohol washes were 0 at the end of Apivar treatment early October. No treatments after Apivar until the 12/15 treatment. Apivar went in the end of August after honey supers were taken off. I used Apistan in the May during package/nuc installs. No treatment in June or July with honey in the supers.

Should I be done or keep going? Effective or not? My Gut tells me retreat A,B,C and the two that don’t have screened bottom boards. But we are forecasted for 8 strait days of rain. I am in Gig Harbor, WA across from Seattle.

 

[FriendsWithGardens]

Burley (between Port Orchard and Gig Harbor). I am susbcribed. I am experiencing the same thing. Am on third treatment. Second dropped 200 mites. I was zero on alcohol washes in October. See what I have tomorrow after the third but three hours in I had 3-5 mites in some hives on bottom boards. 8 hives here.

Greetings from a fellow beek in Port Orchard, not far from you. My bees were VERY active on that nice day we had Jan 1. I need to start my OAV treament ... did it last September but probably time again. Anyway, just saw your post and thought I'd say hi.