Re: May 24 Science Friday broadcast on bees
what many of the varroa resistant populations have in common is that those populations are somewhat isolated, aren't experiencing very high hive densities, and aren't getting moved and mixed and exposed to outside influences like the bees do here in the u.s.
these populations are much like the thriving ferals we have (had?) around here in that they achieve and demonstrate (in relatively short time) host/parasite equilibrium, including equilibrium with the bacteria and viruses.
as has been pointed out, bees like this often fail to thrive when removed from their locale and moved to other locales where they become exposed to different populations of other bees and different populations pests and pathogens.
i am dealing with the opposite scenario here. i.e. bees not having resistance and laden with novel pathogens are being introduced en masse into our local resistant population, mostly by entry level beekeepers purchasing packages to start their apiaries with.
i've been tracking my treatment free survival/loss very closely for a number of years and it has been as good or better than what folks utilizing conventional methods were getting. i've reported an uptick in losses these past two winters and i am currently in the middle of an efb epidemic. i thought it might be the pendulum swinging but all of this coincides with a large number deadouts that occured near my bees over these past three winters that i didn't even know about until recently.
i don't think there is much likelihood that dynamics in play all the way from the large commercials to the beginning hobbyists are going to change, but in my opinion it is these dynamics that are contributing to the stalemate we have in the u.s. with varroa.
that there are many examples of populations that have achieved host/parasite equilibrium is encouraging and teaches us that if the circumstances allow it can and probably will happen. we just don't have those circumstances here and now. frankly, it may be impossible to achieve them.
journaling the growth of a (mite) treatment free apiary started in 2010. 20+/- hives