Over the last quarter century, increasing honey bee colony losses motivated standardized large-scale surveys of managed honey bees (Apis mellifera), particularly in Europe and the United States. Here we present the first large-scale standardized survey of colony losses of managed honey bees and stingless bees across Latin America. Overall, 1736 beekeepers and 165 meliponiculturists participated in the 2-year survey (2016–2017 and 2017–2018). On average, 30.4% of honey bee colonies and 39.6% of stingless bee colonies were lost per year across the region. Summer losses were higher than winter losses in stingless bees (30.9% and 22.2%, respectively) but not in honey bees (18.8% and 20.6%, respectively). Colony loss increased with operation size during the summer in both honey bees and stingless bees and decreased with operation size during the winter in stingless bees. Furthermore, losses differed significantly between countries and across years for both beekeepers and meliponiculturists. Overall, winter losses of honey bee colonies in Latin America (20.6%) position this region between Europe (12.5%) and the United States (40.4%). These results highlight the magnitude of bee colony losses occurring in the region and suggest difficulties in maintaining overall colony health and economic survival for beekeepers and meliponiculturists.

DeepWings© is a software that uses machine learning to automatically classify honey bee subspecies by wing geometric morphometrics. Here, we tested the five subspecies classifier (A. m. carnica, Apis mellifera caucasia, A. m. iberiensis, Apis mellifera ligustica, and A. m. mellifera) of DeepWings© on 14,816 wing images with variable quality and acquired by different beekeepers and researchers. These images represented 2601 colonies from the native ranges of the M-lineage A. m. iberiensis and A. m. mellifera, and the C-lineage A. m. carnica. In the A. m. iberiensis range, 92.6% of the colonies matched this subspecies, with a high median probability (0.919). In the Azores, where the Iberian subspecies was historically introduced, a lower proportion (85.7%) and probability (0.842) were observed. In the A. m mellifera range, only 41.1 % of the colonies matched this subspecies, which is compatible with a history of C-derived introgression. Yet, these colonies were classified with the highest probability (0.994) of the three subspecies. In the A. m. carnica range, 88.3% of the colonies matched this subspecies, with a probability of 0.984. The association between wing and molecular markers, assessed for 1214 colonies from the M-lineage range, was highly significant but not strong (r = 0.31, p < 0.0001). The agreement between the markers was influenced by C-derived introgression, with the best results obtained for colonies with high genetic integrity. This study indicates the good performance of DeepWings© on a realistic wing image dataset.

Cuba is a tropical island where beekeeping is an important economic activity. Cuban honey bees have a European origin, being hybrids of Apis mellifera mellifera and A. m. ligustica. Although Varroa destructor and Nosema are widely distributed in the country, there is no information regarding Nosema species identity and the presence of honey bee viruses. In this study, we report for the first time the presence of Nosema ceranae, Acute bee paralysis virus (ABPV), Deformed wing virus (DWV) and Sacbrood bee virus (SBV) in Cuba. Their detection in different provinces and the simultaneous infection of colonies by several viruses indicate that they are widely spread in Cuba. On the other side, N. apis and Black queen cell virus (BQCV) were not detected.

Historical antecedents of bee introductions, as well as behavioral aspects of the bees, have allowed assuming that Cuban bees are of European origin, and have remained on that way for approximately 60 years of isolation, even though Latin America and the Caribbean region is practically Africanized. In this work, three bees were collected per apiary from 11 localities distributed throughout Cuba and their mitochondrial (by cytochrome b) and nuclear (STRs A8, A28, A43, A88, and A113) variation was characterized. Except for locus A28 (p < 0.001), none significantly deviates from the Hardy–Weinberg equilibrium, and as a whole showed the absence of population structure on the island (Fst = 0.045) and low consanguinity (Fis = −0.135). The Cuban population was compared with reference samples of European, Africanized and Brazilian bees and in all cases showed a moderate differentiation with respect to these populations (Fst paired of 0.156, 0.124 and 0.128 with Europe, Brazil and Africa, respectively). Although this differentiation, the population of Cuban bees shows a clear genetic affinity with the European population. Similarly, most of the samples have mitochondrial haplotypes of European origin (80%), while the rest corresponded to African haplotypes. In short, Cuban bees would have a European origin and would have differentiated in isolation, with a low entry of bees of African lineages.

Varroa destructor has been present in Cuba since 1996, but without the use of acaricidal infestation rates remain at very low levels. The presence of Korean haplotype mites was described in 2007, but there is no information regarding the introgression of the less virulent Japanese haplotype that could account for a low pathogenicity of the mite. In this research, we carried out molecular characterization of Cuban Varroa mites through mitochondrial DNA and hypervariable nuclear loci. We applied an alternative RFLP technique and found that all the analyzed samples corresponded to Korean haplotypes. We analyzed the three STRs loci VD112, VD114 and VD016, previously described as highly variable and found new alleles in all of them, with an absolute allele size very different to those reported worldwide. We also detected genic and genotypic differentiation between samples from two nearby locations (P=0.08). We also tested a new RFLP method for mite haplotype discrimination with an intra-reaction positive control of digestion.