> The national winter loss, including non-viable bee colonies was 32.6% with provincial losses ranging from 18.4% to 45.7%. The overall national colony loss reported in 2018 is the highest reported loss since 2009. Through the hard work of beekeepers replacing loses and making increases, Statistics Canada reports show that the total colony count has increased by 34.1% during the period between 2007 and 2017.

> Respondents reported some variation in identifying and ranking the top four possible causes of colony losses across the country. The most frequently cited causes in order from high to low were: weather, poor queens, weak colonies in the fall and starvation.

-- Canadian Association of Professional Apiculturists Statement on Honey Bee Wintering Losses in Canada (2018)

* Clearly, in the minds of beekeepers, poor queens is a leading cause of colony mortality. Obviously weather cannot be controlled, leaving queen quality as a variable that could be affected. This is a recurring theme in beekeeping with blame directed at various factors. Recent work in Australia points to a large difference in quality between queens raised in spring and fall:

>Queens with an effective mating frequency (ke) greater than 7 are considered adequately mated, whereas queens that fall below this threshold head colonies that have increased likelihood of failure and may be less productive for beekeepers.

> We found that 33.8% of Autumn-produced queens did not meet the threshold, whereas 93.8% of Spring queens were adequately mated. The number of colonies contributing drones to the mating pool was similarly high in both seasons, suggesting that while many colonies have drones, their numbers may be decreased in Autumn and management strategies may be required to boost drone numbers at this time. 

-- Genetic diversity in the progeny of commercial Australian queen honey bees (Apis mellifera) produced in autumn and early spring

PLB

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