The team that worked on the genetic analysis also did similar work with Canadian bees:

Quoted material follows, for review purposes only. 

Distributions of honey bee lineages across Canada: local adaptation or management practices?

We predicted that Northern Canada could favour genotypes derived from honey bee subspecies accustomed to similar environments, such as the M group subspecies. To test this hypothesis, we investigated associations between ancestry (C, M, or A) and geographic location. 

Following corrections for False Discovery Rate (Benjamini and Hochberg 1995), we found a significant negative correlation between M ancestry and latitude (P = 0.008; r = -0.48) and a positive relationship between C ancestry and latitude (P = 0.0046; r = 0.51) indicating that colonies in Northern Canada tended to have higher proportions of C lineage.

We have demonstrated here that contemporary Canadian honey bees are largely derived of C lineage subspecies, similar to populations in the United States. This pattern is likely a result of both North American and Australian beekeepers long favouring C lineage bees for their docility and higher honey production (Langstroth and Dadant 1889). 

Beekeepers have regularly imported and admixed local populations with A. m. ligustica (a practice once called "Italianizing") to introduce these favourable phenotypes. The large C lineage component of Canadian honey bees is likely a result of past importation preferences and the use of "Italianized" colonies that continues today. 

Previous studies have discovered differences in ancestry between feral and commercial populations, with feral bees having higher levels of M ancestry. This pattern is thought to be the result of beekeepers either favouring the use of C lineage bees or selection in feral populations favouring M ancestry. 

We did not include feral populations in our Canada survey. However, we did find that a colony’s location was correlated with its ancestry. North-western Canada had more C ancestry (less M) than South-eastern Canada. This is _counter to expectation_ as northern colonies were expected to be comprised of more northern-derived (i.e. M lineage) ancestry (Oldroyd et al. 1995). 

We attribute this pattern _not to selective differences between parts of the country_, but rather to beekeepers in North-western Canada self-reporting that they import more queens (colonies) from international sources that have higher C ancestry than colonies reported to be purchased within Canada.

Harpur, & al. (2015). Assessing patterns of admixture and ancestry in Canadian honey bees. Insectes Sociaux, 62(4), 479-489.

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