Ask Marla if that is true next time you see her, Or Frank Eishen, or Dewey Caron... These people actually know from first-hand experience and are not making up a new beekeeping religion.
I haven't had the opportunity to talk to Marla Spivak or Frank Eishen before. In March 2010, I did get to hear Dewey caron speak about Africanized Honey Bees. After his presentation, I talked to him and asked him how much of the AHB resistance to varroa was due to the smaller cells and shorter brood development time. He was very dismissive that smaller cells or a shorter development time had anything to do with varroa resistance. He claimed that AHB raised drone brood early in the season, whereas European bees raise drones later in the season, and that was the determining factor in varroa resistance. From his body language and the way he worded things, he gave the impression that it was not politically correct for him to allow the possibility that cell size or development time could affect varroa reproduction.
Sadly, I found myself disappointed and questioning his integrity. I've seen too many people who are afraid to be honest and say something politically incorrect for fear of upsetting the gravy train.
Smaller cells get less feed for the larva due to smaller base area, so the resulting bees may be starved a bit, just like queens which are not well-provisioned.
Are you using closer frame spacing in some hives or experiencing bowed frames? I often wonder with all this emphasis on cell diameter how many people look at cell depth.
Interesting point. I trim my brood frames to 1 1/4 inches wide. The cluster can cover more brood per a given volume this way, and it only takes one layer of bees to fill the gap between frames, rather than two.
It may be a very real possibility that brood do not get fed as good since there is a higher brood population density, added with a reduced population of nurse bees doing feeding.
I have seen smaller bees before in feral hives, and assumed it was due to inadequate pollen stores. Even in my hives when I do see small baby bees, usually it is only a handful of tiny ones, with most being normal sized. Normally I don't see all the bees in a hive being tiny.
In feral hives I have examined, the comb spacing was usually about 1 1/4 inches. It makes me wonder that when feral bees are faced with the decision of keeping more brood covered by tighter comb spacing, versus possibly not being able to adequately feed brood - maybe the tighter comb spacing has a higher net benefit even with some smaller bees due to insufficient feeding.
It's definitely something to think about.
I try to keep tabs on Bee-L. Recently, a link was posted about a South African beekeeper who has experience with AHB. I glanced at the link and found some really interesting info that raises several questions.
The pedigreed bees (left) get only a small strip of foundation at the top of the frame, and build the comb themselves to the prefered cell size. During the selection process the bees have been upgraded in size, and now build 5,2 mm cells, like european bees. The wild bees build cells around 4.8-4.9mm.
Wild bees (right) build smaller cells.
(bottom of the page)
I 'think' pedigreed bees are bees he has bred.
How are scutellata bees upgraded to draw larger cells?
Why do some scutellata draw small cells, and why do some draw larger cells?
If you can get bees to upgrade to larger cell size, is that the opposite of the regression to smaller cells that people do to European bees?
These are foundationless frames in the pictures. The bees should be drawing cell sizes that are 'natural' to them. If we can quickly change the bees mental imprinting of the proper cell size...what really is the proper cell size?
Starting to go off topic...there is also a page on a varroa study.
They examined cell size, and the number of mites, and what caste and gender of mites were in the cells.
I do not know how the study was conducted exactly, or how long the study took place.
From what I understand, the mite climbs in the cell, has male and female babies, and the daughter and son mites mate before emergence from the cell. From the chart in the study, it would appear to be a significant difference in mite reproduction, even though they ended up with total numbers of mites in all samples.
Distrubution of offspring 640 cells/sq.dm 770 cells/sq.dm 900 cells/sq.dm Total
Both female and male ......73 89 85 247
Only female ..................27 11 32 70
Only male ....................10 17 17 44
Only protonymph ............22 23 8 53
No offspring .................18 10 8 36
Total ........................ 150 150 150 450
Cells with only females - unsuccessful reproduction.
Cells with only males - unsuccessful reproduction.
Cells with immature mites - unsuccessful reproduction
Cells with no offspring - unsuccessful reproduction.
Only cells with male and females were able to mate. Small cell with 73 was the lowest. That is 82%-86% of the successful reproduction of mites in other cell sizes. (Is 14%-18% less mites sufficient to affect bee colony survival?)
B. Farmer Honey