Randy >The take home message is that since we've imported perhaps every known
strain of honey bee to the U.S., that all options for hybridization have
already been offered to the hard winnowing by natural selection. 


I'm not sure what you mean Randy but below is research from Coby et al. that suggests that the U.S. never imported all the subspecies to achieve full allelic diversity. The paper also argues that other bottlenecks continued to restrict diversity.  Those included are the initial loss of feral colonies to varroa and the practice of queen breeders using restrictive queen lines. 


>In considering genetic diversity, it is instructive to realize that the honey bee populations originally introduced into North America were filtered through two structural genetic “bottlenecks” (Figure 1). First, the initial “sampling” of each subspecies chosen for importation consisted of a few tens to hundreds of queens, representing only a small fraction of the genetic diversity within each subspecies. Secondly, only nine of the more than two dozen named Old World subspecies found within the species Apis mellifera were ever introduced into the Americas. Thus, overall “sampling” of the within-species diversity was only partial, with 2/3 of the named subspecies never having been introduced into the Americas. Subsequent to the initial importations, additional losses of genetic diversity could have been expected due to “genetic drift.” Genetic drift can be thought of as changes in gene frequencies across generations due to chance or as the effect of inbreeding in small populations, both of which can lead to loss of allelic diversity.

>Queen-rearing operations range in size and production, mostly between 5,000 to 150,000 queens produced annually. Often, only a few queen mothers are used for propagation and with little control of mating areas. Concentrated in northern California and the southwest, completely isolated mating is not an option and producers depend upon each other to supply adequate drone sources for mating yards.

What are the implications for our breeding efforts if in fact there's a lack of genetic diversity in our domestic stock?  


Status of Breeding Practices and Genetic Diversity in Domestic U.S. Honey Bees

Susan W. Cobey1,2, Walter S. Sheppard2 and David R. Tarpy



Bill Hesbach
Northeast US 

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