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Abstract 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. 

Different microclimates can have significant impact on the physiology of succulents that inhabit arid environments such as the Mojave Desert (California). We investigated variation in leaf physiology, morphology and anatomy of two dominant Mojave Desert monocots, Yucca brevifolia (Joshua tree) and Hesperoyucca whipplei , growing along a soil water availability gradient. Stomatal conductance ( g s ) and leaf thickness were recorded in the field at three different sites (north-western slope, south-eastern slope, and alluvial fan) in March of 2019. We sampled leaves from three individuals per site per species and measured in the lab relative water content at the time of g s measurements, saturated water content, cuticular conductance, leaf morphological traits (leaf area and length, leaf mass per area, % loss of thickness in the field and in dried leaves), and leaf venation. We found species varied in their g s : while Y. brevifolia showed significantly higher g s in the alluvial fan than in the slopes, H. whipplei was highest in the south-eastern slope. The differences in g s did not relate to differences in leaf water content, but rather to variation in number of veins per mm 2 in H. whipplei and leaf width in Y. brevifolia . Our results indicate that H. whipplei displays a higher water conservation strategy than Y. brevifolia . We discuss these differences and trends with water availability in relation to species’ plasticity in morphology and anatomy and the ecological consequences of differences in 3-dimensional venation architecture in these two species.