Something seems to be changing for the worse regarding varroa mites in  
the US.  More than two treatments needed per year?  Untreated colonies  
rapidly getting to treatment thresholds?  Neighbors producing "mite  
bombs" that obliterate the effects of treatments?  Calls for  
coordinated timing of regional treatments?  "Treatment free"  
approaches not advisable?  Viruses running amuck?

In the early days of varroa mites, once beekeepers got over the  
initial learning curve, it was possible to have healthy colonies year  
round.  Many who tried "IPM" approaches (reduced number of treatments,  
cultural controls, treatments after reaching thresholds, etc.) seemed  
to be successful.  Feral bees appeared to be recovering in some areas.

What has changed from the 80s and 90s to now?  The miticide arsenal is  
failing.  Formerly isolated drone congregation areas are being flooded  
with highly susceptible drones by the growing number of hobbyists and  
sideliners.  Colonies are being kept broody (and producing drone  
brood) year round for pollination in California.

Not treating colonies appears to have produced "sustainable"  
situations a good number of times and in various places (e.g. Brazil,  
Puerto Rico, Gottland).  It also has led to complete or almost  
complete elimination of all colonies in a small number of cases (Santa  
Cruz Island, Bermuda).  The US is not an island, but there may be  
lessons to pick up in a number of places.

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