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- Accounting for detection unveils the intricacy of wild boar and rabbit co-occurrence patterns in a Mediterranean landscapePublication . Barros, Ana Luísa; Curveira-Santos, Gonçalo; Marques, Tiago André; Santos-Reis, MargaridaThe patterns of species co-occurrence have long served as a primary approach to explore concepts of interspecific interaction. However, the interpretation of such patterns is difficult as they can result from several complex ecological processes, in a scale-dependent manner. Here, we aim to investigate the co-occurrence pattern between European rabbit and wild boar in an estate in Central Portugal, using two-species occupancy modelling. With this framework, we tested species interaction for occupancy and detection, but also the interdependencies between both parameters. According to our results, the wild boar and European rabbit occurred independently in the study area. However, model averaging of the detection parameters revealed a potential positive effect of wild boar's presence on rabbit's detection probability. Upon further analysis of the parameter interdependencies, our results suggested that failing to account for a positive effect on rabbit's detection could lead to potentially biased interpretations of the co-occurrence pattern. Our study, in spite of preliminary, highlights the need to understand these different pathways of species interaction to avoid erroneous inferences.
- Modelling the distribution of Mustela nivalis and M. putorius in the Azores archipelago based on native and introduced rangesPublication . Lamelas-López, Lucas; Pardavila, Xosé; Borges, P.A.V.; Santos-Reis, Margarida; Rosário, Isabel Amorim Do; Santos, Maria J.The aims of this study were to predict the potential distribution of two introduced Mustelidae, Mustela nivalis and M. putorius in the Azores archipelago (Portugal), and evaluate the relative contribution of environmental factors from native and introduced ranges to predict species distribution ranges in oceanic islands. We developed two sets of Species Distribution Models using MaxEnt and distribution data from the native and introduced ranges of the species to project their potential distribution in the archipelago. We found differences in the predicted distributions for the models based on introduced and on native occurrences for both species, with different most important variables being selected. Climatic variables were most important for the introduced range models, while other groups of variables (i.e., human-disturbance) were included in the native-based models. Most of the islands of the Azorean archipelago were predicted to have suitable habitat for both species, even when not yet occupied. Our results showed that predicting the invaded range based on introduced range environmental conditions predicted a narrower range. These results highlight the difficulty to transfer models from native to introduced ranges across taxonomically related species, making it difficult to predict future invasions and range expansion.
- Drivers of wood mouse body condition in Mediterranean agroforestry landscapesPublication . Fragoso, Ricardo; Santos-Reis, M.; Rosalino, L. M.Agriculture and pastureland for cattle grazing are common land uses in Mediterranean landscapes. These activities significantly alter the habitat conditions, affecting the body conditions of wild communities, especially those with low vagility, such as small mammals. We aimed to evaluate how cattle grazing and the habitat composition affected the body condition of the wood mouse Apodemus sylvaticus in a southern Mediterranean agroforestry system using the Scale Mass Index (SMI) as an indicator of individuals condition. To assess variation in body condition, wood mice were live-trapped in a gradient of grazed sites with different stocking intensities, as well in sites excluded to grazing at different time periods (1998, 2004, and 2008). Wood mice body conditions were influenced by both microhabitat and macrohabitat drivers, with sex-biased patterns, while for the females, only the shrub species had an influence (a microhabitat variable); for the males, both the shrub species and the undercover density (and specifically their interaction) were the important drivers (microhabitat and macrohabitat variables). Unexpectedly, the physical condition variation detected between periods was not directly proportional to the exclusion period, but rather, a certain degree of similarity was found between the different sites (sites excluded since 2004 paired with grazed sites). These results suggest that the presence of food and shelter are determinants to the wood mouse’s physical condition: for females, securing food sources enhance the body condition, while for males, the degree of cover, and consequently refuge against predators, seems to be determinant. These results reinforce the need for sustainable landscape management to assure the maintenance of habitat heterogeneity.
- Valuing and mapping cork and carbon across land use scenarios in a Portuguese montado landscapePublication . von Essen, Marius; Rosário, Inês T.; Santos-Reis, Margarida; Nicholas, Kimberly A.The ecosystem services approach can inform decision-making by accounting for both short- and long-term benefits from different land use options. Here we used the InVEST toolkit to quantify and map key ecosystem services at the largest publicly-owned agro-silvo-pastoral farmstead in Portugal-a site representative for the montado landscape. We analyzed how Provisioning (cork production) and Regulating & Maintenance (carbon storage and sequestration) services would be affected under three land use change scenarios, which were developed in collaboration with the forest manager of the study area: Cattle Intensification, Forest Improvement, and Residential Development. Results show that increasing cattle or residential development would deliver substantially lower levels of services. We find that extensive management, improvements to forest quality, and promotion of traditional livestock grazing would provide the highest levels of assessed ecosystem services, resulting in 13.5% more carbon storage (worth between $0.34-$7.79 million USD depending on carbon price) and 62.7% more cork production (total value of USD $3.5 million) than the current land use. However, a shift in economic incentives to make sustainable cork harvesting and traditional low-density grazing of smaller ruminants like sheep and goats profitable are likely needed to reward traditional land stewardship and help support this iconic Mediterranean landscape in the future.