A lot of discussion is going on which role neonicotinoides and gmo play for die offs and ccd of bee colonies. A poison is never beneficial, neither for bees nor for man (well, many are used as plant protection). And residual substances are more difficult to discover and many times not much less dangerous.
To be able to find the true truth we want the whole picture. Sometimes new facts don’t seem to fit into the picture you have endorsed.
I got this mail from Larry Garret in Indiana in the Corn, Soybeans and Wheat belt, where neonicotinoids and gmo are used overflowing. There he took care of a feral colony that local people told him had been there in the abandoned house for 7-8 years. Now the farmer didn’t want to drive around the house with the tractor anymore, so he asked Larry to rescue the bees.
The wax filled 146 liter of the 255 liter big cavity in the wall. He harvested 20 kg of honey and many buckets of wax. The longest comb was 244 cm. Cell size was between smaller than 5.1 mm to 5.3 mm. Drone cell size was between 6.5 and 6.6 mm. The entrance was close to the bottom.
This colony was thriving in spite of a lot of plant protection poisons. Remember the conclusion that die offs are due to a complex of causes. Evidently when some are missing the bees can stand the others better.
These bees didn’t get a massive reinvasion of pests and parasites from neihgboring colonies. They didn’t have to stand miticides or an unnormal big cell size. They lived on their own food and weren’t fed HFCS.
Were they Varroa resistant? We don’t know. But we learn somewhat about favorable circumstances from which such bees can benefit.