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En la Argentina, la Ecorregion Pampeana presenta bajo nivel de proteccion debido a su alto valor economico y al dominio privado. El reemplazo de sus ambientes naturales por usos productivos causo la retraccion numerica de especies como el carpincho (Hydrochoerus hydrochaeris), que habita sus humedales. Los aspectos biologicos y ecologicos de esta especie permanecen poco estudiados en la provincia de Buenos Aires. En consecuencia, los objetivos de este estudio fueron estimar las abundancias real y relativa, la densidad y el tamano poblacional, y determinar la estructura de la poblacion, el patron de actividad de los individuos en las dos lagunas presentes en el area natural protegida “El Morejon”, partido de Campana, Buenos Aires. Para ello, a lo largo del ano 2014 se realizaron relevamientos de transectas de rastros y trampas camara en las cuatro estaciones. A pesar de estar inmersa en un area urbanizada e industrializada, se obtuvo un tamano poblacional mayor al esperado. Se estimo la presencia de un promedio de 15 individuos en la Laguna 1 y 154 en la 2, en areas de uso estimadas de 3 y 10 ha, respectivamente. Durante el invierno se registro el mayor numero de individuos, y en otono, primavera y verano, los menores. Es posible que esto se asocie a la movilidad de los individuos en busca de alimento. Estos resultados son relevantes para una planificacion correcta de medidas de manejo, y confirman la importancia de que existan reservas privadas que conserven el ecosistema natural de la region.

Context: Modifications in natural landcover generally result in a loss of habitat availability for wildlife and it’s persistence will depend largely on their spatial configuration and functional connections. Argenteohyla siemersi is a threatened and endemic amphibian whose habitat is composed of forest patches near rivers and water bodies edges. Objectives: This study aimed to analyse the accessible habitat for this species and identify key elements to maintain its ecological network in two different types of land uses: an anthropized area with extensive cattle raising and a protected area. Methods: The structural and functional characteristics of both landscapes were analyzed. The connectivity at landscape level and the contribution of each habitat patch were evaluated through simulation models with different dispersion distances in the context of the graph theory. Results: In both landscapes, nine types of landcover were identified with different compositions. Remarkable differences were found in habitat connectivity for this amphibian species between both landscapes. As the percentage of dispersion distance increases, reachable habitat increases as well, although with higher percentages in the protected area. Two corridors were identified in the protected landscape and one in the rangeland one; patches and key links constituted all of them. Conclusions: The present work provides spatially explicit results with a quantitative basis. It could be useful as a tool for the development of management plans aimed at guaranteeing the functionality of the ecological network for this endangered species and, therefore, contribute to its long-term conservation. Fil: Schivo, Facundo Mauro. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; Argentina Fil: Mateo Sánchez, María Cruz. Universidad Politécnica de Madrid; España Fil: Bauni, Valeria. Fundación de Historia Natural Félix de Azara; Argentina. Universidad Maimónides; Argentina Fil: Quintana, Ruben Dario. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; Argentina

El Monumento Natural Isla Palacio es un area natural protegida de 160 hectareas en la provincia de Misiones que fue establecida luego de la creacion del embalse producto de la represa construida sobre el Arroyo Urugua-i. Fue muy estudiada a mitad del siglo XX por distintos naturalistas y cientificos. Tras varias decadas de transformacion de su entorno se presenta un inventario de su flora y fauna luego de 21 anos de relevamientos periodicos. Fueron registrados nueve anfibios, 16 reptiles, 141 aves, 37 mamiferos y 104 especies de flora. A pesar de su escasa superficie, el area alberga especies de valor especial para la conservacion y sobre todo, conserva una referencia historica, folclorica y cultural.

Amphibians are a valuable indicator group to study potential impacts of climate change (CC) because reproduction is closely linked to the availability of freshwater. Climate projections for the humid subtropical region of South America predict an increase in temperature towards the southwest and an increasing of precipitation during the rainy season and decreasing during the dry season. In this context, we aimed to predict the changes in the distribution range of amphibian species and the variation in their richness. In addition, we attempted to determine the most vulnerable species in terms of the extent of habitat loss and the overlap of optimal species distributions by contrasting present and future species range. We modelled the current and future distribution of 55 amphibian species using an inductive approach to model the ecological niche with three different algorithms. We used WorldClim data for current climate and IPPC5 climate projections from Global Climate Model for two greenhouse gas concentrations at 2050. Depending on the CC scenario, between 48 and 57% of the species showed a decrease in their optimal distribution, and 9–10% of them are likely to be affected by further population fragmentation. We identified three types of patterns of change in the geographical distribution of the optimal areas: (I) reduction, (II) displacement, and (III) increase in their distribution range. Future new areas with favourable conditions may not be reached due to the low dispersion tendency of amphibians. For this reason, it is important to identify those current favourable areas that are maintained in the different future scenarios. In this sense, this study allows to highlight priority areas for the conservation of the studied species and to identify those being highly vulnerable to the predicted scenarios. Our results contribute to the knowledge of how different future climates scenarios could affect the conservation of the studied amphibian species and provide key information for the development of strategies and public policies for management and biodiversity conservation.

Bauni, V., Anfuso, J., Schivo, F. 2017. Wildlife roadkill mortality in the Upper Parana Atlantic forest, Argentina. Ecosistemas 26(3): 54-66. Doi.: 10.7818/ECOS.2017.26-3.08 The expansion of transport networks is one of the greatest threats to biodiversity, leading, among other things, to increasing risk of wildlife mortality from accidents. The objective of the present study is to evaluate the roadkills that occurred between 2012 and 2016 in a 34 km segment along the National Route No. 12 in the Upper Parana Atlantic forest (Argentina). This segment crosses several natural reserves and supports massive touristic flow. The number of road accidents was compared between seasons of the year, type of vegetation and presence of protected areas, using mixed generalized linear models. We mapped the distribution of accidents to identify critical sites. During the 47 months surveyed, we observed 1784 roadkills: 67.5% mammals, 25.2% birds and 7.3% reptiles. The species with the greatest number of recorded accidents was the white-eared opossum (Didelphis albiventris), followed by the black-and-white tegu (Tupinambis merianae) and the tropical screech owl (Megascops choliba). Only the reptiles showed significant differences in roadkills between seasons. 72.6% of the accidents occurred in areas with presence of native forest. 70.7% of accidents occurred within protected areas. We identified 13 critical kilometers where the application of measures such as the placement of speed reducers and the adequacy of drainage structures of streams as underpasses are proposed. Once the proposed measures have been implemented, their long-term effectiveness should be evaluated.

The Yacyretá dam is one of the most important hydroelectric projects in La Plata Basin. As a consequence of the filling of the reservoir to its final height of 83m, approximately 1,076km2 of terrestrial and riparian ecosystems were flooded in Argentina and Paraguay. In order to evaluate the ecosystem loss due to this impounding, we generated two maps of land use/land cover from Landsat satellite images: 1987 (prior to the dam) and 2011 (after the final height was reached). We applied a post classification method and tested the gain, loss, and net change of natural and anthropic ecosystems in the study area with a cross tabulation matrix. Water bodies were the land cover type that showed the greatest degree of change, increasing 14.8% between periods. This was in detriment of, primarily, wetlands by 7.5%, grasslands by 4.0%, and native forests by 2.8%. However, sandbanks presented the highest probability of transition to another land class and, thus, correspond to the most vulnerable land cover in the study area. Also, we detected a differential ecosystem loss, both in type and magnitude, up and downstream of the dam. Our work is the first one to address ecosystem loss in the Yacyretá area and our results should help to improve management policies, such as the design of the current network of compensatory reserves. Fil: Bauni, Valeria. Fundación de Historia Natural Félix de Azara; Argentina Fil: Schivo, Facundo Mauro. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Capmourteres, Virginia. Fundación de Historia Natural Félix de Azara; Argentina Fil: Homberg, Marina. Fundación de Historia Natural Félix de Azara; Argentina

The Southern Cone Mesopotamian savanna (MS), located in northeastern Argentina, is one of the least protected ecoregions (0.11%) of the country. Five of the seven historically present species of xenarthrans in this region are of conservation concern at the national level. This work reviews, updates and analyzes the current distribution and conservation status of the xenarthrans using a georeferenced database including records from four complementary methods: field surveys, interviews with local stakeholders, participatory monitoring, and bibliography review. Results were then compared with existing distribution maps. In total, 304 occurrence records were documented in 127 localities. Considering their relative presence (number of localities where the species is present divided by the total number of localities), the species with most records were Dasypus novemcinctus (71.7%) and Dasypus hybridus (63%); Euphractus sexcinctus and Tamandua tetradactyla were detected in a lower proportion (48.8 and 3...