Conservation Status of the Argentine Boa Constrictor (Boa constrictor occidentalis) 20 Years After Being Listed in CITES Appendix I

Twenty years after the species was listed in CITES Appendix I, we carried out a comprehensive review of the conservation status of the Argentine Boa Constrictor (Boa constrictor occidentalis) in Argentina. We compiled background information on trade, biology, and distribution. We evaluated the historical range on the basis of museum and literature records, and later adjusted it to  incorporate environmental variables. We carried out 573 interviews with local residents regarding the historical presence of the species and the ways in which it was used. Using a rapid assessment of woody vegetation cover, we estimated the degree of habitat loss in Argentina. We conclude that CITES has been very effective in stopping the international trade and almost completely eliminating hunting pressure on this snake throughout Argentina. However, suitable boa habitat has been reduced by one third to approximately 30 million ha from a historical extent of occurrence of about 42 million ha in the Dry Chaco ecoregion. Loss of suitable habitat is mainly  due to recent expansion in agricultural and livestock production. This subspecies is still common  throughout its range; however, recent trends in habitat loss led us to conclude that the Argentine Boa Constrictor meets at least one of the CITES criteria for retention in Appendix I, at least until the recently enacted forest protection law proves its effectiveness in protecting the remaining Chaco forests of Argentina

El potencial invasor de la vegetación espontánea en los agroecosistemas

¿Todas las plantas que crecen asociadas a los cultivos son perjudiciales? En función de quien reciba la pregunta, la respuesta puede ser “depende”. En los agroecosistemas existen dos grandes grupos de diversidad biológica: la biodiversidad planificada, que refiere a los cultivos y animales incluidos en el agroecosistema por el productor; y la biodiversidad asociada, que incluye la flora y fauna (incluso la del suelo) que colonizan al agroecosistema desde los ambientes circundantes, o desde el banco de semillas, tratándose de plantas...Fil: Herrera, Lorena Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Estavillo, Candelaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Echevarria, Maria Lis. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Diez de Ulzurrum, Patricia. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentin

Perda de habitat, leis ambientais e conhecimento científico: proposta de critérios para a avaliação dos pedidos de supressão de vegetação

Que problema ambiental é foco deste trabalho? A ausência de um protocolo pragmático e com base ecológica para a avaliação de viabilidade ambiental em processos de autorização de supressão de vegetação nativa (ASV).Qual foi a estratégia do trabalho para contribuir com sua solução? Integrar conhecimento acadêmico e aplicado a partir do diálogo entre técnicos ambientais e ecólogos visando desenvolver um protocolo com essas caraterísticas.Qual é a principal conclusão do trabalho? O uso de uma árvore de decisões que integra três escalas espaciais e explicita critérios de precaução tem potencial para qualificar os pareceres técnicos sobre ASV

Specific differences in habitat requirement drive responses to habitat loss and disturbance in Atlantic Forest small mammals

As deforestation proceeds, habitat is lost in the landscape and the human-created matrix augments. Species that differ in their habitat requirements and tolerance to disturbance should not be equally affected by habitat loss and degradation. Forest dependent species should be more affected by these effects than generalist species that can use more than one habitat type. On the other side, non-native species should benefit from environmental degradation. In this work, we compared the responses of three assemblages of small mammals (forest specialist, generalists and open area dwelling species) along a gradient of forest cover in five landscapes of the Atlantic Forest. We followed the responses of the assemblages in native forests and in non-forested matrices, observing diverse responses in adjacent environments within a forest-matrix system. As was expected, the specialists were the most affected by the loss of native habitat; they decayed considerably in richness and abundance below 35% of habitat in the landscape. Generalist species were not affected by the quantity of habitat in the forest but, conversely, they were positively affected by moderate levels of disturbance in the matrix. Open area species did not colonize the forest irrespective of coverage and they were the dominant assemblage in the disturbed, matrix environment.Cnpq, Capes, FapesbSalvado

Trabajadores rurales y riesgo zoonótico: Entendiendo la ecología de los animales silvestres que transmiten enfermedades

La Eco-epidemiología estudia la relación entre humanos, vida silvestre y transmisión de enfermedades. Esta relación puede ser compleja y dependiente de contexto, lo que lleva a preguntarnos si existen generalidades en la influencia de los factores biológicos sobre la salud humana. En este trabajo, investigamos las especies de mamíferos transmisoras de enfermedades zoonóticas en el sudeste bonaerense. Analizamos el supuesto de que las especies que crecen y se reproducen más rápido son los reservorios zoonóticos más probables. El conocimiento ecológico de las especies, junto con datos de salud pública, pueden proveer información importante para la vigilancia epidemiológica y el manejo del riesgo zoonótico.Fil: Estavillo, Candelaria. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Weyland, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Herrera, Lorena Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentin

Zoonotic Disease Risk and Life-History Traits: Are Reservoirs Fast Life Species?

The relationship between humans, wildlife and disease transmission can be complex and context-dependent, and disease dynamics may be determined by idiosyncratic species. Therefore, an outstanding question is how general is the finding that species with faster life histories are more probable hosts of zoonoses. Ecological knowledge on species, jointly with public health data, can provide relevant information on species that should be targeted for epidemiological surveillance or management. We investigated whether mammal species traits can be good indicators of zoonotic reservoir status in an intensified agricultural region of Argentina. We find support for a relationship between reservoir status and the pace of life syndrome, confirming that fast life histories can be a factor of zoonotic risk. Nonetheless, we observed that for certain zoonosis, reservoirs may display a slow pace of life, suggesting that idiosyncratic interactions can occur. We conclude that applying knowledge from the life history-disease relationship can contribute significantly to disease risk assessment. Such an approach may be especially valuable in the current context of environmental change and agricultural intensification.Fil: Estavillo, Candelaria. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Weyland, Federico. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Herrera, Lorena Paola. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentin

Familiarity and mating behavior in the subterranean rodent Ctenomys talarum (tuco-tuco)

Biological odors that convey cues regarding individual identity are known to alter mating behavior in some rodents. Deposition of chemical signals by males on the substrate could give females information about their neighbors’ identity and allow familiarization with their odors. This study tested whether familiarization of females with conspecific male odors affects mating behavior in Ctenomys talarum Thomas, 1898, facilitating mating as a consequence of a decrease in aggressive behavior and an increase in sexual behavior. Tuco-tucos are solitary subterranean rodents that occupy and defend adjacent burrows. Both sexes usually scent-mark burrow openings, providing odor signals to neighbors during their aboveground patrolling and foraging activities. Hence, familiarity by odor cues may represent an important mechanism that mediates neighbor recognition and probably mate selection. In this study, familiarity was established by housing females with male odors for 8 days. In C. talarum, individual recognition by olfactory cues may reduce mating costs when pairing with neighbors, since females showed low aggression towards familiar males and copulations were not repeated in consecutive days. Females that were not exposed to male odors were more aggressive, but surprisingly these pairs copulated repeatedly.Les odeurs biologiques qui transmettent des signaux sur l’identité individuelle peuvent modifier le comportement d’accouplement chez certains rongeurs. Le dépôt de signaux chimiques par les mâles sur le substrat peut fournir aux femelles des renseignements sur l’identité de leurs voisins et leur permettre de se familiariser avec ces odeurs. Notre étude vérifie si la familiarisation des femelles de Ctenomys talarum Thomas, 1898 avec les odeurs de mâles de la même espèce affecte le comportement d’accouplement et facilite l’accouplement en diminuant les comportements agressifs et en favorisant les comportements sexuels. Les tuco-tucos sont des rongeurs souterrains solitaires qui occupent et défendent des terriers adjacents. Les animaux des deux sexes marquent l’entrée de leur terrier avec des odeurs, ce qui fournit des signaux olfactifs aux voisins qui patrouillent et recherchent leur nourriture au-dessus du sol. C’est pourquoi, la familiarité avec les signaux olfactifs peut servir de mécanisme important pour la reconnaissance des voisins et peut-être pour le choix des partenaires. Dans notre recherche, nous avons établi la familiarité en logeant des femelles en présence d’odeurs mâles pendant 8 jours. Chez C. talarum, la reconnaissance des individus à l’aide de signaux olfactifs peut réduire le coût de l’accouplement lorsque celui-ci se fait entre voisins, puisque les femelles montrent peu d’agressivité envers les mâles familiers et il ne se produit pas de copulations répétées au cours des jours consécutifs. Les femelles non exposées aux odeurs mâles sont plus agressives, mais, de façon inattendue, les couples alors formés copulent à répétition.Fil: Zenuto, Roxana Rita. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Estavillo, Candelaria. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Fanjul, Maria Sol. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentin

Can rural tourism stimulate biodiversity conservation and influence farmer's management decisions?

The Pampean agroecosystems are oriented to providing a few Ecosystem Services (ES) with undesired consequences on the environment, particularly the loss of biodiversity and cultural ES. In this context, it is necessary to find ways to make agricultural production compatible with biodiversity conservation through sustainable practices. Rural tourism is a form of productive diversification that generates additional economic income for farmers and may encourage the conservation of uncultivated semi-natural environments. Thus, agroecosystems could provide a greater variety of ES, achieving their multifunctionality. For this, it is necessary to understand the link between land use and biodiversity and the psycho-social factors that stimulate or limit farmers to conserve their field´s semi-natural environments. To this end, we conducted a study with three approaches: 1) we evaluated the intentions of rural Pampa´s farmers of conserving uncultivated environments through surveys analyzed under the framework of the Theory of Planned Behavior, 2) we explored the preferred environments for recreation through a self-administered survey to rural tourists, and 3) we conducted bird surveys to associate land use with biodiversity. The results showed a trend of greater intention to conserve uncultivated environments in farmers with rural tourism than without rural tourism. These intentions were related to more positive attitudes due to the intrinsic and utilitarian values of conserving uncultivated environments and less identification with agriculture only as a source of economic income. Tourists preferred semi-natural environments for recreation, which also sustain higher bird diversity. Results allowed to detect key aspects to influence farmers to achieve a greater intention to conserve uncultivated environments and manage them to supply multiple ES.Fil: Weyland, Federico. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Laboratorio de Agroecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Colacci, Paloma. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Laboratorio de Agroecología; ArgentinaFil: Cardoni, Daniel Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Estavillo, Candelaria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Laboratorio de Agroecología; Argentin

PLoS ONE

p. 1-10Habitat loss is the main driver of the current biodiversity crisis, a landscape-scale process that affects the survival of spatially-structured populations. Although it is well-established that species responses to habitat loss can be abrupt, the existence of a biodiversity threshold is still the cause of much controversy in the literature and would require that most species respond similarly to the loss of native vegetation. Here we test the existence of a biodiversity threshold, i.e. an abrupt decline in species richness, with habitat loss. We draw on a spatially-replicated dataset on Atlantic forest small mammals, consisting of 16 sampling sites divided between forests and matrix habitats in each of five 3600-ha landscapes (varying from 5% to 45% forest cover), and on an a priori classification of species into habitat requirement categories (forest specialists, habitat generalists and open-area specialists). Forest specialists declined abruptly below 30% of forest cover, and spillover to the matrix occurred only in more forested landscapes. Generalists responded positively to landscape heterogeneity, peaking at intermediary levels of forest cover. Open area specialists dominated the matrix and did not spillover to forests. As a result of these distinct responses, we observed a biodiversity threshold for the small mammal community below 30% forest cover, and a peak in species richness just above this threshold. Our results highlight that cross habitat spillover may be asymmetrical and contingent on landscape context, occurring mainly from forests to the matrix and only in more forested landscapes. Moreover, they indicate the potential for biodiversity thresholds in human-modified landscapes, and the importance of landscape heterogeneity to biodiversity. Since forest loss affected not only the conservation value of forest patches, but also the potential for biodiversity-mediated services in anthropogenic habitats, our work indicates the importance of proactive measures to avoid human-modified landscapes to cross this threshold