This research using pin puncture tests on squares of 100 purple-eyed pupae conducted over three years during all seasons evaluated hygienic behavior, among other traits, in what they refer to as bees subjected to "strong breeding efforts".  The bees included different gene lines from many geographic locations. 


>  The GLM analysis showed that hygienic behaviour was not significantly affected by year or origin. The trait was instead highly significantly
(p < 0.01) affected by season, location and genotype (Table 2). The highest expression of the trait was estimated in July and August, while
the lowest was estimated in May and autumn (Table 7). 

Comment: The above results follow what has been reported in most of the research referenced below, that hygienic behavior increases as conditions change, especially around the honey flow. I'm getting that it's not a matter of whether a behavior changes, rather it's the colony level expression that varies as needed (Robinson,1992). In the case of increased honey flow, hygienic behavior is reported to increase accordingly.   

>Seasonal differences in expression of hygienic behaviour have been frequently reported (Panasiuk et al., 2009; Güler and Toy, 2013), but
there are also contradictory reports (Bigio et al., 2013). It is likely that season and location interact to yield unique combinations of floral
availability and nectar flow, which are known to influence the expression of hygienic behaviour (Momot and Rothenbuhler, 1971; Robinson, 1992;
Spivak and Gilliam, 1998a,b; Johnson, 2003). Furthermore, according to several authors, hygienic behaviour is mainly exhibited by workers
that are younger than three weeks (Thompson, 1964; Arathi et al., 2000; Panasiuk et al., 2010), and different balance of young and old bees in
the colony may affect expression the trait at the colony level. This may, for example, explain the lower cleaning rate we observed in autumn. 

>Swarming, defensive and hygienic behaviour in honey bee colonies of different genetic origin in a pan-European experiment
Aleksandar Uzunov et al. 

https://www.tandfonline.com/doi/pdf/10.3896/IBRA.1.53.2.06



Bill Hesbach
Cheshire CT. 

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