My first mention of "mite leveling" (minus that precise terminology) was here and written back in 2005 or 2006. Well before Jennifer's study. I for one think Jennifer Berry is a very smart and I happen to like her a lot. Don't know where you get this stuff. That doesn't mean I agree with her results. I recently added a quote to back up the concept, but the rest has been there for five years or so.
"...some people have observed a sudden increase to thousands and thousands of mites in a short time. Part of this is, of course, all the brood emerging with more mites. But I believe the issue is also that the FGMO (and many other systems as well) manage to create a stable population of mites within the hive. In other words the mites emerging is balanced out by the mites dying. This is the object of many methods. SMR queens are queens that reduce the mites' ability to reproduce. But even if you get to a stable reproduction of mites, this does not preclude thousands of hitchhikers coming in. Using powdered sugar, small cell, FGMO or whatever that gives an edge to the bees by dislodging a proportion of the mites, or preventing the reproduction of mites and seems to work under some conditions. I believe these conditions are where there are not a significant number of mites coming into the hive from other sources...
"Conditions that cause the mites to skyrocket seem to be in the fall when the hives rob out other hives crashing from mites and bring home a lot of hitchhikers."
http://www.bushfarms.com/beespests.htm#varroa
To imply this is a recent "excuse" is simply not true. I've been saying this all along as have others.
Sorry, MB.
Robbing to show mite transfer is very different than the mite leveling excuse used after Berry's study came out. It's not about suggesting because mite were seen to drift in a yard, or could peak with a robbing condition. I think everyone in the bee industry has understood that for years.
We are talking about hives in the same yard, void of robbing, under controlled studies, all being relatively the same mite counts, due to the suggestion that mite transfer at a rate that one could not distinguish between a smallcell have and another standard hive.
Again, after THOUSANDS of mite counts, drastic differences CAN be seen in individual yards between different hives. Mite do transfer, but nowhere near the rate that could blow away the data and make smallcell and large cell hives all the same mite counts. If that were the case, you would see standard mite counts being the same in all yards. Beekeepers for years have tried to suggest a "threshhold" to determine which hives one should treat. That way, beekeepers could treat those needing help, and not treat the others. If mites "leveled out", it would be suggested that all hives should be treated or not treated based on one hive's mite count. And we know that not to be the case. Hive's individual abilities to handle and deal with mites are drastically different and huge differences in mite counts can be seen within the same yard. And that is why it was shocking to most, even the smallcell crowd, by the fact that the mite counts were not seen as different in the studies.
Heck, we even seen and collected data on mite count differences between hives in shade vs sun in the same yard. Certainly we should be able to see differences between mite counts when one was supposed to inhibit mites (smallcell) and one was supposed to be a mite multiplier (large cell).
For the record MB, Can you post when was the first time you actually used the definition of "mite leveling". Not the idea, that mites drift or infect other nearby hives by robbing, etc., but the actual use of the idea of "mite leveling", which is what was used to discredit Berry's study. Thanks. I checked beesource and found no use of the term by you till after I started using it to describe the "excuse" given to rationalize the smallcell failure in Berry's study.