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Background: The inclusion of information on the phenology of any given species can significantly improve the resulting of potential distribution models. Scientific literature does not provide up-to-date information on the abiotic and biotic factors that determine the distribution of Croton guatemalensis, a species native to communities in south Mexico. For the first time, the potential distribution of C. guatemalensis was determined using a model which includes reproductive biology data. Questions: Which bioclimatic and climatic variables most contribute to the distribution of C. guatemalensis? Does reproductive biology data contribute significantly to the prediction of the species distribution? Studied species/Mathematical model: Croton guatemalensis/ Maximum Entropy Modeling Study area and dates: Chiapas, Mexico, January - December 2020. Methods: The MaxEnt 4.4.4 algorithm was used, incorporating 16 variables, including bioclimatic, climatic and elevation. In addition, a habitat suitability layer was built. Results: The model presented a precision of AUC = 0.964 ± 0.004. Eight variables contributed to explain 86.5 % of the potential distribution of the species. According to their contribution to the model, the most important were the seasonality of precipitation, habitat suitability, elevation and April solar radiation. The species was found in the physiographic regions Central America South Mountain Range Subprovince, Central Depression of Chiapas Discontinuity, and Altos de Chiapas Subprovince. Conclusions: The inclusion reproductive biology data of C. guatemalensis contributed to improve the model. This information allows the development of more effective management and conservation plans by identifying the precise regions in which the species is found.

Oaxaca hosts one of the greatest biodiversity in México, occupying first place in avian diversity compared to other regions of the country. However, the area is undergoing serious problems such as high deforestation rates, soil erosion and over exploitation and extinction of species. These factors have all contributed to the current loss of biodiversity. Also, biological inventories are still incomplete. One of the least explored sites is the semiarid zone of Tehuantepec isthmus, around the locality of Santa Maria del Mar, Oaxaca, México. The area includes floodable grasslands, mangrove areas and dry forest, providing a range of potential habitats for different species. Our objective was to evaluate the effect of temporal lakes on spatial and temporal composition of the avifauna in Santa Maria del Mar, in order to generate information regarding this group within the region and the state, and to understand the importance of flood areas for resident and transitory birds. We conducted 12 avifauna surveys between July 2006 and June 2008, and established two transects of 2km length in each of four habitat types (beach, grassland, dry forest, and mangrove). We found a total of 75 species, corresponding to 16 orders and 30 families. Within an area of 26km², we significantly found 10.1% of the total number of bird species recorded for the entire state, and 6.6% of the total reported in Mexico. The families most represented were: Ardeidae, Laridae and Scolopacidae. Over the entire study period, dry forest was the most diverse habitat; followed by mangrove, grassland and the beach. Of all the species recorded, 38.6% were found at the edge or in the temporal lakes. We found a significant difference in species composition between seasons in the grassland, but no difference in the other habitats. Our results showed a significant effect of temporary lakes on avian diversity during the wet season; it also demonstrated the importance of grassland conservation given its relevance for presence of waterbirds. We suggested a continued and more intense monitoring; and proposed the designation of the area as an important Conservation Bird Area (AiCA).

Es de gran importancia conocer y evaluar las enfermedades zoonóticas emergentes que existen en el sureste de México, ya que representan una amenaza significativa para la salud pública. Los cambios antropogénicos, por ejemplo, la deforestación, el establecimiento de monocultivos, el aumento de la urbanización y la densidad poblacional humana son responsables de la mayoría de las enfermedades infecciosas emergentes zoonóticas. Pronósticos de eventos emergentes indican que en los países con ambientes tropicales (como México) existe una mayor diversidad de zoonosis transmitidas por animales silvestres, por lo que debemos contener y dar rápida respuesta ante posibles brotes de dengue hemorrágico y otras fiebres hemorrágicas virales (FHV). Es importante contar con datos actualizados de las posibles áreas de distribución y ecosistemas de las especies de mamíferos (en particular roedores y murciélagos) que potencialmente pueden ser reservorios o vectores de varias de las FHV, crear modelos con información base para contener brotes de FHV, así como determinar los cambios en los ambientes y la distribución de especies afectadas por actividades humanas.