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Land use and cover change have a high influence on bee species, where honey bees (Apis mellifera) could be affected in terms of resources, dispersal, and habitat. However, the influence of landscape context on honey productivity has been scarcely explored in comparison with population parameters, which is an essential topic for the economic development of rural communities based on apiculture. Here, we tested the hypothesis if honey production decreases with the increase of exotic forest plantations in the landscape as the cover of native forest decreases, vegetation and soils become increasingly degraded. We compiled data on honey productivity for two years (2018 and 2019) of small-scale honey production in 17 landscapes of 1 km radii (Curanilahue state in south-central Chile). Then, the landscapes were characterized by using remote sensing techniques, including biophysical and compositional landscape variables. Finally, Generalized Linear Mixed Models were implemented to explore the relationship between landscape variables and honey productivity. We identified a positive relationship between honey productivity with built cover and grassland cover. On the other hand, a negative relationship was found between honey production and net primary production, exotic forest plantations, and tree senescence index. Our results provide new insights into the landscape-scale drivers of hive productivity in rural landscapes of south-central Chile. [ABSTRACT FROM AUTHOR]

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Aim: Primary cavity nesters (e.g. woodpeckers) act as ecosystem engineers by providing tree cavities to several vertebrates that use them as nests or refuges. Although diverse assemblages of primary excavators are assumed to increase the number of tree cavities, environmental factors can limit populations of primary excavators, thus weakening their ecological function. We aim to test the biogeographical‐scale relationships between primary excavators and cavity users by distinguishing the contribution of environmental variables. Location: Southern South America. Materials and Methods: We used species distribution models, which combine bioclimatic and remote sensing derived variables, to map the richness of vertebrates composing the cavity‐network of temperate and Mediterranean forests of South America. Based on a resampling procedure for ensuring spatial independence, we fitted structural equation models to estimate relationships between forest characteristics and cavity user vertebrates. Results: Richness of secondary cavity users (mammals, obligated, habitat generalists and forest specialists) were positively and strongly influenced by the richness of primary excavators. Environmental variables affected differently the richness of primary and secondary cavity users. The richness of primary cavity users responded to tree richness and height while that of habitat specialist secondary users was positively affected by primary productivity and negatively by sclerophyll forests. Main Conclusions: Our results confirm the role of primary excavators as ecosystem engineers but highlight the importance of considering large spatial scales when analysing cavity‐nesting networks. Biogeographical patterns of tree diversity and forest structure can be important drivers of cavity nesting networks that remain hidden when studies are conducted over fine spatial scales. [ABSTRACT FROM AUTHOR]

Links between ecosystem collapse and biological invasions have been scarcely documented with empirical field measurements. In Chile the recent collapse of Aculeo lake, which was the largest natural freshwater body of the Central zone of Chile, produced a serious socio-environmental crisis in the local population. Here, we aim to report the concerning densities of the highly invasive Bagrada hilaris in this recently collapsed ecosystem. Densities of B. hilaris in plots combined with mapping of the area covered by infested plants allowed us to estimate the size of the B. hilaris population. Densities of B. hilaris in the dried lake reached 628.88 ± 95.28 ind/m2 and the infested area amounted to 310 ha, representing 26% of the total lake area. The population of B. hilaris in the dried Aculeo Lake reached 1948.9 ± 295.3 million individuals. Here we highlight the need for control actions to avoid a potential invasion over important nearby crops and protected areas, and the link between freshwater ecosystem collapse with the rapid colonization of invasive species. [ABSTRACT FROM AUTHOR]