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1. The painted lady Vanessa cardui is a long‐range migratory butterfly that performs an annual multi‐generational round‐trip between Europe and Africa. Each autumn it returns to northwest (NW) Africa, presumably to track changes in resources that follow a predictable climate‐related spatio‐temporal pattern. 2. Data on the abundance of adult and immature stages in the Maghreb in 2014–2016 are used to test several hypotheses regarding the autumn migration of this species. 3. A strong seasonal migratory strategy was confirmed by the all but total absence of the species in NW Africa at the end of summer and the arrival of huge numbers migrants in October and November. Migration was timed to coincide with an increase in host plant availability but not with any increase in nectar sources. 4. Flower abundance was the main predictor of adult abundance in autumn, with Ditrichia viscosa, Verbesina encelioides, and Medicago sativa being key resources that attracted enormous numbers of butterflies to oases, ruderal habitats, and oueds. The distribution of immature stages was strongly predicted by host plant abundance (with traditional agriculture representing the most important breeding habitat) and latitude (most breeding occurred in the south of the region). Also, both adults and immature stages were more common inland than in coastal areas. 5. Changes in age structure of the adult population were also noted. The number of fresh adults slowly increased, indicating that butterflies did not return in a single wave and that the first offspring of the first returners were already emerging when some butterflies were still arriving.

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1. Conserving functionally diverse bird communities in European farmland is becoming critical, with no exception for regions of wine production. Management intensification combined with the loss of semi-natural habitats in wine-growing landscapes has led to a long-term decline not only in birds of conservation concern but also in once common insectivores and seed eaters. These declines are expected not only to threaten key ecological services provided by vineyard birds, such as pest or weed control, but also their cultural significance.2. We analysed how organic management and landscape heterogeneity affected taxonomic and functional diversity of 334 bird communities from 12 regions of the three main wine-producing European countries (France, Italy and Spain). We further modelled the responses of community-level metrics measuring mean habitat specialization and bird song attractiveness to humans, as well as cumulative abundances of functional insectivores, seed and grape eaters to account for individual avian functions.3. We found that organic viticulture enhanced bird functional diversity and individual functions, but that its positive effect partially depended on grass cover management in the inter-rows and landscape heterogeneity. Woodland cover and landscape compositional heterogeneity increased both taxonomic and functional diversity of bird communities, as well as functional insectivory. Landscape

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