Small Cell Studies

[WLC]

This one? (Berry)

http://www.ent.uga.edu/bees/documents/m08138.pdf

Or, this one? (Ellis)

http://www.springerlink.com/content/lk80j0017v01w026/

Which one is refined?

[sqkcrk]

The whiter one, of course.

[deknow]

...id like to discuss the seeley paper....its the most recent, tom has an excellent reputation for doing good work. Wlc, thanks for the link..I didnt know it was freely available.
Deknow

[K Wieland]

Very interesting indeed, and I would like to discuss it as well.

1.I didn't understand the part about cutting out the drone cells. It was my understanding that the mites prefer the drones (is this true?) and so the drones are sacrificial.
2. As he noted, the small cell seemed to do poorly. Can this alone explain the difference? Hives under stress are naturally more susceptible to mites, right?
2. A followup study would be interesting to see a test of foundationless vs standard frame, with no drone removal.

[hpm08161947]

I would have thought with no drone larvae available, the mites would have been placed at a disadvantage. Seemingly not. Perhaps his control was LC with no drone cells... guess I need to reread.

[Barry]

Haven't finished reading it, but so far I have a couple of things that give rise.

One on wax comb, the other on plastic.
Study done for such a short period.
The whole measuring bees part I don't get. How long after bees emerged were they measured? Why measure bees? A more accurate measurement of bee to cell ratio would be to measure the bee before it emerges.

[Michael Bush]

Dee proposed long ago that one, if not the main effect, of large cell is the pseudo drone effect. Which is that the Varroa mistake the worker cells for drone cells and therefore infest both drones and workers.

I have stated here on beesource before ( http://www.beesource.com/forums/show...705#post486705 ) that perhaps the cause of higher counts during the spring with small cell in the experiments that have been done, is because there are a lot of drones reared in the spring and the mites on small cell are more efficient at reproducing during that period because of the abundance of drone cells. As the drone cells fall off more later, those get infested even more and probably result in drone mortality at that point, but that may actually mean the Varroa are less successful because they are killing their host, and since they aren't infecting the workers (which they are not mistaking for drones) they are not less successful later in the year so that the Varroa population curve may spike in early spring and drop off by fall. I do not cull drone comb at all, and I have a LOT of drone comb because I do foundationless and never throw out drone combs and yet in the fall I have trouble finding Varroa. I think it was a huge mistake for Seeley to remove all the drone comb and drone cells. It removes one of the primary and likely theories on how small cell works. But counting mites also leads to erroneous conclusions unless you track the population over a couple of years minimum. But I think counting mites is a mistake. Counting survivors when not treating would be a more useful test.

[Solomon Parker]

... perhaps the cause of higher counts during the spring with small cell in the experiments that have been done, is because there are a lot of drones reared in the spring and the mites on small cell are more efficient at reproducing during that period because of the abundance of drone cells.

As I mentioned before, I see this in my hives. I have crawlers in the spring, but later in the year, they disappear.

[Oldtimer]

Actually that's an interesting theory Michael. Should be easy enough to test, just via some brood sampling.

Howzabout doing it, and reporting back?

[Michael Bush]

>Howzabout doing it, and reporting back?

I'm still out of the country and will be doing major catch-up when I return, so I'm sure I won't have time. But the theory is consistent with the counts that Seeley did with no drone brood (no difference in SC and the mites had no choices) and the counts that Berry got when she did not remove drone brood (more mites in SC hives but that was in only two months in the spring).

[Oldtimer]

Hmmm.... Well I'll try it with mine then, although at this point I only have 2 sc hives, and last time I checked the brood could not find a varroa. But during the season I'll do running brood samples, and if there's anything interesting I'll start a thread on it. I've allowed each hive to build two drone combs, so it's doable.

The only potential weakness in the theory is that it would rely on drones dying in the cells. Otherwise mite numbers would just continue to increase ad infinitum until the hive was overun.

But anyhow the idea is definately worth testing & I'd encourage anyone else who can, to try some tests also and report back, to provide some more data.

[Michael Bush]

I pretty much have to check for mites in June if I want to see any... but if you start with very low numbers and the spike in June and fall off then you have few at the beginning again. I have them inspected every year and only if I have them inspected late does the inspector find any. Which is consistent with my experience as well.

Inspection certificates since 2004:
http://www.bushfarms.com/beescerts.htm

[Oldtimer]

I'm on the other side of the world from you. Different seasons.

Do you have brood through the winter?

[Michael Bush]

>Do you have brood through the winter?

Some of the time. They tend to raise a little patch and then they take a break and then raise another little patch up until pollen starts coming in.

[beemandan]

The whole measuring head and thorax thing was to address the contention that in the smaller cells the pupae size restricted movement of the male mite, who was therefore unable to feed. The study suggests that the size difference would not have created sufficient restriction.

I do think the size may be important. Bee size is genetic. I have any number of traditional cell hives that have bees of widely varying size. Some quite small and many of their sisters large. Yet I’ve often heard small cell beekeepers talk about their noticeably smaller bees. I regressed a number of hives some years ago and I was unable to see any difference in bee size . Based on Seeley’s head and thorax measurements (they evidently didn’t measure abdominal size), the size difference on sc was around 2 – 3%. To my way of thinking, assuming that the same percentage applies to the abdomen, this would not be a visible difference….certainly not enough for a beekeeper to talk about his little bees.

Dennis Murrel (sp?), Kirk Webster and even Dee Lusby have spoken of a major collapse before becoming successful with sc. So, is it possible that during the conversion to small cell, following the collapse, the only bees that will be successful are the genetically smaller bees and that those bees, as a result of their reduced size have a shorter pupation period? And were this the case, would those same genetically smaller bees fare just as well on traditional cell? It is simply that the sc beekeepers forced out the larger bees.

Just one of my pet theories.

[Michael Palmer]

...Kirk Webster...have spoken of a major collapse before becoming successful with sc.

Kirk Webster has a major crash about every other year, and rebuilds his apiary from what is left of his production hives and nucleus colonies.

[beemandan]

Kirk Webster has a major crash about every other year

Whooops!
Ok...it should read....Dennis Murrel (sp?) and even Dee Lusby......

[Barry]

The whole measuring head and thorax thing was to address the contention that in the smaller cells the pupae size restricted movement of the male mite, who was therefore unable to feed. The study suggests that the size difference would not have created sufficient restriction.

I understand the reason for measuring. Why did they measure the bees at some time (this time frame is not given) after they emerged? Why would you not measure the bee while still in the cell before other factors come into play? My experience is that I will see significantly smaller bees in the spring and fall, but during the summer flow months, all bees look the same size.

[beemandan]

Why would you not measure the bee while still in the cell before other factors come into play?

I can't imagine that it would make a dramatic difference. It would complicate the study significantly though. They would have to go into the hives many more times to determined and mark new eggs, then return and find those specific aged pupae....and what age would they choose? Or would they have to test multiple ages.

My experience is that I will see significantly smaller bees in the spring and fall, but during the summer flow months, all bees look the same size.

Do you believe that you can visually identify a 2-3% difference as 'significantly smaller bees'.

I know I won't be missed but must go....and likely won't be back before next week....

[Kieck]

Sclerotized parts of insect exoskeleton don't change size. The width of the head remains the same throughout adulthood for insects. Same is true for hard parts of the thorax and abdomen. The width of the first abdominal tergite is the same from the first day after exclusion to the last. I think the argument about measurements is a digression from this discussion.