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In Chile, many aspects of the ecology of bats and their distribution are unknown, despite their ecological and economic importance. This situation does not allow a correct implementation of conservation efforts even when they are legally recognized as beneficial animals for agriculture. Here, we studied the bats' activity and community in two agricultural landscape types (homogeneous vs. heterogeneous) in a hotspot of biodiversity in the centre‐south of Chile. We monitored four transects of 10 km per landscape type with 10 listening points separated by 1 km. These transects were repeated 5 times, once per month. We evaluated the bats activity according to the forest cover type (native, mixed and plantations) and the isolated trees density. Our results showed that the heterogeneous landscape was dominated by T. brasiliensis while the homogeneous landscape was by Lasiurus spp. However, only the species T. brasiliensis was affected by the landscape type. In the heterogeneous landscape, only the forest cover variables had significance in the activity of the bat species, where Lasiurus spp. and M. chiloensis had a positive response for native and mixed forest, as well as Lasiurus spp. had a negative response for plantations. The density of isolated trees had a negative effect on the activity of T. brasiliensis and Lasiurus spp. in the homogeneous landscape type. Our results showed the importance of considering the forest elements in agroforestry landscape to conserve bat communities.

ResumenA pesar de su importancia ecológica y económica, en Chile se desconocen muchos aspectos de la ecología de los murciélagos y de su distribución. Esta situación no permite una correcta implementación de los esfuerzos de conservación aún cuando son legalmente reconocidos por sus beneficios para la agricultura. En este trabajo estudiamos la actividad y la comunidad de murciélagos en dos tipos de paisaje agrícola (homogéneo vs. heterogéneo) en un hotspot de biodiversidad en el centro‐sur de Chile. Para ello, monitoreamos cuatro transectos de 10 km en cada tipo de paisaje, con 10 puntos de escucha separados por 1 km. Estos transectos se repitieron 5 veces, una vez al mes. Evaluamos la actividad de los murciélagos según el tipo de cobertura forestal (nativa, mixta y plantaciones) y la densidad de árboles aislados. Nuestros resultados mostraron que el paisaje heterogéneo fue dominado por Tadarida brasiliensis mientras que el paisaje homogéneo fue dominado por Lasiurus spp. Sin embargo, sólo la especie T. brasiliensis fue afectada por el tipo de paisaje. En el paisaje heterogéneo, sólo las variables de cobertura forestal tuvieron un impacto significativo en la actividad de las especies de murciélagos, donde Lasiurus spp. y Myotis chiloensis tuvieron una respuesta positiva para bosque nativo y mixto, así como Lasiurus spp. tuvo una respuesta negativa para plantaciones. La densidad de árboles aislados tuvo un efecto negativo sobre la actividad de T. brasiliensis y Lasiurus spp. en el tipo de paisaje homogéneo. Nuestros resultados muestran la importancia de considerar los elementos forestales en el paisaje agroforestal para conservar las comunidades de murciélagos.

Aim Applying wide and effective sampling of animal communities is rarely possible due to the associated costs and the use of techniques that are not always efficient. Thus, many areas have a faunistic hidden diversity we denote Animal Dark Diversity (ADD), defined as the diversity that is present but not yet detected plus the diversity defined by Pärtel et al. (2011) that is not (yet) present despite the area’s favourable habitat conditions. We evaluated different species distribution model types (SDM techniques) on the basis of three requirements for ADD estimate reliability: 1) estimated spatial patterns of ADD do not differ significantly from other SDM techniques; 2) good predictive performances; and 3) low overfitting. Location Iberian Peninsula. Taxon Chiroptera and Noctuoidea (Lepidoptera) Methods We used distribution data for 25 species of bats and 352 species of moths. We evaluated eleven SDM techniques using biomod2 package implemented in the R software environment. We fitted the various SDM techniques to the data for each species and compared the resulting ADD estimates for the two animal groups under three threshold types. Results The results demonstrated that estimated ADD spatial patterns vary significantly between SDM techniques and depend on the threshold type. They also showed that SDM techniques with overfitting tend to generate smaller ADD sizes, thus reducing the possible species presence estimates. Among the SDMs studied, the ensemble models delivered ADD geographic patterns more like the other techniques while also presenting a high predictive performance for both faunal groups. However, the Ensemble Model Committee Average (ECA) performed much better on the sensitivity metric than all other techniques under any of the thresholds tested. In addition, ECA stood out clearly from the other ensemble model techniques in displaying low-medium overfitting. Main conclusions SDM techniques should no differ among each other in their ADD estimations, have good predictive performances and exhibit low overfitting. Furthermore, to reduce estimate uncertainty it is suggested that the threshold type be one that transforms high values of presences probabilities into binary information and furthermore that the SDM technique have a sensitivity bias, as otherwise the estimates will perform better for species absence in cases where it is not in fact known whether a species is truly absent.