> Resistant stock surrounded by commercial > nonresistant stock is often overwhelmed by the immigration of varroa from > the nonresistant stock. I wonder how often this is the case and how serious it is compared to the dilution of the resistant stocks from surrounding susceptible stocks and degeneration of the resistant qualities from queen replacement. Replacement goes on non-stop from both natural supersedure in the hives (occurring at rates of around 30% from what I have heard reported) and from queen production by the beekeepers themselves, using cells -- both purchased and homegrown. Obtaining, proving and maintaining resistant stock in a sizable operation is not a trivial undertaking. Maintaining resistant qualities through generations requires expertise and dedication as the procedures are time-consuming and require education and discipline or purchase of stock from a trusted breeder who does all the necessary verification. Even then, bees which have been found to be sufficiently resistant to be productive without treatments in one region may turn out to be unsatisfactory in that regard under different conditions. I recall that Danka and his group were following some migratory bees around the US a few years back and in fact I saw them at Merrimac Apiaries several summers ago and saw some of the stock being observed. Some of them were surviving untreated fairly well as I recall. I wonder how that all worked out. I've missed the US meetings in recent times and if there were reports, I have not seen them. I'd be interested in the latest news on that front. *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html