Signature of Environmental and Parasite Stresses on the Wings of Apis mellifera

The decline of pollinators, particularly Apis mellifera, seriously threatens global ecosystems and agricultural productivity. This study investigated the effects of environmental stress (low vegetation cover, high internal hive temperatures, high internal hive humidity, and high parasitism rate by the mite Varroa destructor) on the fluctuating asymmetry (FA) of honey bee wings in seven apiaries in Dom Joaquim, a reference city for wild honey production in the state of Minas Gerais, Brazil. We evaluated the FA of 18 wing venations of 30 bees from five beehive boxes in seven apiaries, totaling 1050 bees. Our results showed that fluctuating asymmetry (FA) in wing venation traits M4 (P = 0.013), M12 (P = 0.014), M13 (P = 0.020), M14 (P = 0.014), and M18 (P < 0.001) differed significantly among apiaries, likely reflecting variation in local environmental stressors. These differences suggest that site-specific conditions may differentially impact colony stress levels, influencing developmental stability in honey bees. We also noted that the apiaries with lower native forest cover (<50%) and lower floral diversity showed higher FA in the M17 venation. Furthermore, internal hive conditions, such as elevated temperature and mite infestation, were associated with increased FA in venation traits M2 and M18. In contrast, higher humidity levels were linked to increased FA in traits M4 and M17. In general, the results highlight that the FAs of the M2, M17, and M18 wing venations are associated with multiple stress factors, suggesting that the FAs of these venations are the most recommended for use. This research also emphasizes the importance of preserving native vegetation and managing hive conditions to maintain the health and stability of honey bee populations. These results also demonstrate the potential of FA as a bioindicator of environmental stress in A. mellifera, which may help improve beekeeping management practices.