The influence of population-control methods and seasonality on the activity pattern of wild boars (Sus scrofa) on high-altitude forests

The wild boar (Sus scrofa) is a problematic invasive species which has colonized the threatened Brazilian Atlantic Forest. Our objective was to evaluate if population control and seasonality affect the circadian rhythm of wild boar activity. Wild boar activity was monitored by camera-traps for 1 year without population-control methods and 1 year with population control methods implemented in the area. Before population control was implemented, wild boar activity was uniform across 24 h, with animals being active at any given time (cathemeral). After the population control, wild boars concentrated their activities on the daylight period. Also, wild boars were more active during the wet season, possibly influenced by the presence of seeds of Araucaria angustifolia trees. Based on these results, control measures should be conducted during the wet season and different management strategies, such as the use of rifes with telescopic sights and silencers, should be tested

Biodiversity and elevation gradients: Insights on sampling biases across worldwide mountains

Identifying macroecological patterns and biases in species distribution is a challenging but essential task in biodiversity-oriented studies. Despite extensive attempts to find consistent species richness elevation (SRE) patterns, the topic remains controversial owing to widespread conflicting, idiosyncratic and non-generalizable underlying mechanisms. We used a meta-analytical review to answer why patterns of species-richness in elevation gradients remain elusive, a long-standing, central but contentious macroecological and biogeographical question. Location: Global elevation gradients. Taxon: Major terrestrial taxa (invertebrates, vertebrates and plants). Methods: We tested the effect of elevation on species richness using multilevel mixed-effects meta-analytical models. Data from 127 studies spawning almost one century of research were integrated to test the effect of elevation across distinct (1) SRE models, (2) quality of primary data (e.g. mountain sampling coverage), (3) biogeographic realms, (4) studied taxa and (5) organism mobility. Results: The linear negative pattern showed the strongest model fit followed by the hump-shaped and the linear positive models. Studies with higher sampling sizes showed a consistent decrease in the strength of SRE patterns. Further, the larger the mountain coverage and sampled range, the stronger the detection of some SRE patterns. Overall, the elevational effect on species richness was consistent across biogeographical realms, taxonomic groups and organism mobility. Main Conclusions: This study indicates a bias in the detection of SRE patterns, driven mostly by mountain comprehensiveness, namely the number of sampling units, sampled range and mountain sampling coverage. These results call attention to the evidence that undersampled elevation gradients may bias our understanding on the complex relationships between elevation and biodiversity, thus impairing a broad understanding on the ecology, evolution, biogeography and conservation of mountain biota.Fil: Costa, Fernanda Vieira da. Universidade Federal de Minas Gerais; BrasilFil: Barbosa Viana Júnior, Arleu. Universidade Estadual da Paraiba; BrasilFil: Aguilar, Ramiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional Autónoma de México; MéxicoFil: Silveira, Fernando A. O.. Universidade Federal de Minas Gerais; BrasilFil: Cornelissen, Tatiana G.. Universidade Federal de Minas Gerais; Brasi