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Global warming is influenced by an increase in greenhouse gas (GHG) concentration in the atmosphere. Consequently, Net Ecosystem Exchange (NEE) is the main factor that influences the exchange of carbon (C) between the atmosphere and the soil. As a result, agricultural ecosystems are a potential carbon dioxide (CO2) sink, particularly rice paddies (Oryza sativa). Therefore, a static chamber with a portable CO2 analyzer was designed and implemented for three rice plots to monitor CO2 emissions. Furthermore, a weather station was installed to record meteorological variables. The vegetative, reproductive, and maturation phases of the crop lasted 95, 35, and 42 days post-sowing (DPS), respectively. In total, the crop lasted 172 DPS. Diurnal NEE had the highest CO2 absorption capacity at 10:00 a.m. for the tillering stage (82 and 89 DPS), floral primordium (102 DPS), panicle initiation (111 DPS), and flowering (126 DPS). On the other hand, the maximum CO2 emission at 82, 111, and 126 DPS occurred at 6:00 p.m. At 89 and 102 DPS, it occurred at 4:00 and 6:00 a.m., respectively. NEE in the vegetative stage was -25 µmolCO2 m2 s-1, and in the reproductive stage, it was -35 µmolCO2 m2 s-1, indicating the highest absorption capacity of the plots. The seasonal dynamics of NEE were mainly controlled by the air temperature inside the chamber (Tc) (R = -0.69), the relative humidity inside the chamber (RHc) (R = -0.66), and net radiation (Rn) (R = -0.75). These results are similar to previous studies obtained via chromatographic analysis and eddy covariance (EC), which suggests that the portable analyzer could be an alternative for CO2 monitoring.

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Jaguars and pumas are top-predator species in the Neotropics that are threatened by habitat destruction, illegal poaching of their body parts and their favored prey, and by the human-wildlife conflicts that arise when predators attack livestock. Much of the remaining felid habitat in the Americas is in protected nature reserves that are too small and isolated to support local populations. Surrounding forests therefore play a vital role in felid conservation. Successful long-term conservation of these two felids requires evidence-based knowledge of their biological and ecological requirements. We studied population distributions of jaguars and pumas and their prey in and between two small, private reserves of the Northern Yucatán Peninsula, Mexico, with areas of 25 and 43 km2. During 2 years of camera trapping (2015 and 2016), we detected 21 jaguars, from which we estimated an average space requirement of 28-45 km2/individual. Dietary niche overlap exceeded random expectation. The most frequently occurring prey items in jaguar and puma diets were collared peccary and deer. Jaguar also favored nine-banded armadillos and white-nosed coati, while puma favored canids. Both felids avoided ocellated turkey. Overall, diet of jaguars was less species-rich, but similar in niche breadth, to that of pumas. A fluid use of space by both species, in 2015 tending toward mutual attraction and in 2016 toward partial exclusion of pumas by jaguars, combined with the high dietary overlap, is consistent with a dominance hierarchy facilitating coexistence. Jaguars and pumas favor the same prey as the people in local communities who hunt, which likely will intensify human-wildlife impacts when prey become scarce. We conclude that even small reserves play an important role in increasing the continuity of habitat for prey and large felids, whose generalist habits suppress interspecific competition for increasingly limiting prey that are largely shared between them and humans.

Los jaguares y pumas son las principales especies depredadoras del Neotrópico. Se encuentran amenazados por la destrucción de su hábitat, la caza furtiva de sus partes corporales, así como de sus presas favoritas, y por los impactos entre humanos y vida silvestre que surgen cuando estas especies atacan al ganado. Gran parte del hábitat protegido de los felinos restante en las Américas lo constituyen reservas naturales que son demasiado pequeñas y aisladas para por sí mismas sustentar las poblaciones locales de estas especies. Por lo tanto, los bosques circundantes juegan un papel vital para la conservación de estos felinos. La conservación exitosa a largo plazo de estas dos especies de felinos necesita conocimiento basado en evidencia de sus requerimientos biológicos y ecológicos. Estudiamos la distribución de poblaciones de jaguares y pumas, y sus presas, en dos pequeñas áreas protegidas privadas del norte de la península de Yucatán, México, con áreas de 25 y 43 km2, y en el área no protegida de 250 km2 que se encuentra entre ellas. Durante un estudio de foto-trampeo de dos años (2015 y 2016), detectamos 21 jaguares, a partir de los cuales estimamos requerimientos espaciales de 28­45 km2/individuo en promedio. La superposición entre nichos alimentarios superó las expectativas aleatorias. Las presas más frecuentes en las dietas del jaguar y el puma fueron el pecarí de collar y los venados. El jaguar también favoreció al armadillo de nueve bandas y coatí de nariz blanca, mientras que el puma favoreció a los cánidos. Ambos felinos evitaron al pavo ocelado. En general, la dieta de los jaguares presentó menor riqueza específica, pero similar amplitud de nicho a la de los pumas. Un uso fluido del espacio por parte de ambas especies hizo que en un año tendieran a tener atracción mutua y en otro a una exclusión parcial por parte de los jaguares a los pumas, lo cual, en combinación con la alta superposición alimentaria, es consistente con una jerarquía de dominancia que facilita la convivencia. Los jaguares y los pumas favorecieron las mismas presas que la gente que caza en las comunidades locales, lo que probablemente intensificará los impactos entre humanos y vida silvestre cuando las presas escaseen. Concluimos que incluso las reservas pequeñas desempeñan un papel importante en el aumento de la continuidad del hábitat para presas y grandes felinos, cuyos hábitos generalistas suprimen la competencia inter-específica por presas cada vez más limitadas que en gran parte comparten con los humanos.

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In xeric environments, such as Caatinga Biome, habitat characteristics such as phytophysiognomy type and presence of water bodies can represent higher resource availability. In this context, the present study investigated the effect of phytophysiognomies and presence of water bodies in the abundance and community structure of medium and large mammal species (MLM) in the Serra de Santa Catarina, Paraíba, Brazil. To evaluate these variables we conduct an effort of 373 camera-trap days, between August 2012 and November 2014. We recorded 12 MLM species, distributed in six orders and 11 families. From those, Kerodon rupestris is the only one listed in the Brazilian List of Threatened Fauna. Regarding the habitat, the Mann-Whitney showed a significant higher frequency to the Shrubby habitat and the ANOSIM showed no shifts in the community structure between Arboreal and Shrubby. Concerning the presence of water bodies, both the Mann-Whitney and the ANOSIM showed significant higher frequency to the habitat with water presence. We observed that both phytophysiognomy and water bodies are important variables which affect mainly the abundance of mammalian species from semiarid environments. Nonetheless, whereas the forest remnants get smaller the existence of water bodies becomes a preponderant factor to the MLM species and its community structure.(AU)

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Several forest types compose the apparently homogenous forest landscape of the lowland Amazon. The seasonally flooded forests (igapós) of the narrow floodplains of the blackwater rivers of the Amazon basin support their community of animals; however, these animals are required to adapt to survive in this environment. Furthermore, several taxa are an important source of seasonal resources for the animals in the adjacent unflooded forest (terra firme). During the low-water phase, the igapó becomes available to terrestrial species that make use of terra firme and igapó forests. Nonetheless, these lateral movements of terrestrial mammals between hydrologically distinct forest types remain poorly understood. This study tested the hypothesis that the attributes of the assemblages (abundance, richness, evenness, and functional groups) of the terrestrial mammals in both these forest types of the Cuieiras River basin, which is located in the Central Amazon, are distinct and arise from the ecological heterogeneity induced by seasonal floods. After a sampling effort of 10,743 camera trap days over four campaigns, two for the terra firme (6,013 trap days) and two for the igapó forests (4,730 trap days), a total of 31 mammal species (five were considered eventual) were recorded in both forest types. The species richness was similar in the igapó and terra firme forests, and the species abundance and biomass were greater in the terra firme forest, which were probably due to its higher primary productivity; whereas the evenness was increased in the igapós when compared to the terra firme forest. Although both forest types shared 84% of the species, generally a marked difference was observed in the composition of the terrestrial mammal species. These differences were associated with abundances of some specific functional groups, i.e., frugivores/granivores. Within-group variation was explained by balanced variation in abundance and turnover, which the individuals of a given species at one site were substituted by an equivalent number of individuals of a different species at another site. However, the occupancy was similar between both forest types for some groups such as carnivores. These findings indicate that seasonal flooding is a relevant factor in structuring the composition of terrestrial mammal assemblages between terra firme and floodplain forests, even in nutrient-poor habitats such as igapós. The results also highlight the importance of maintaining the mosaic of natural habitats on the scale of the entire landscape, with major drainage basins representing management units that provide sufficiently large areas to support a range of ecological processes (e.g., nutrient transport, lateral movements and the persistence of apex predators).

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Dogs are the most abundant carnivores on earth and, as such, negatively impact wildlife. Free-ranging dogs roam in many protected areas, which in turn are often tourist destinations. Whether tourists influence their roaming is largely unexplored but highly relevant to wildlife conservation. To address this question, we obtained (i) 81 completed questionnaires from tourists on their experience with free-ranging dogs in the remote Cape Horn Biosphere Reserve, Chile, and (ii) photographs of three camera-traps placed next to trekking trails (n = 87 trap days). A third of the participants were followed by dogs for up to four days, and 39% saw free-ranging dogs on their hikes, but neither feeding dogs nor fear of them had any influence on whether tourists were followed by dogs. Camera-traps yielded 53 independent dog sequences, recorded 32 individuals plus 14 unidentified dogs, of which only one was leashed, with a frequency of one dog every 28th person. In 17% of 53 sequences, dogs were photographed together with hikers carrying large backpacks for several-day trips. We conclude that tourists are facilitators for the movement of dogs and highlight the importance of the engagement of the tourism sector in wildlife conservation in and close to protected areas.

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Abstract Mammals are charismatic organisms that play a fundamental role in ecological functions and ecosystem services, such as pollination, seed dispersal, nutrient cycling, and pest control. The state of São Paulo represents only 3% of the Brazilian territory but holds 33% of its mammalian diversity. Most of its territory is dominated by agriculture, pastures, and urban areas which directly affect the diversity and persistence of mammals in the landscape. In addition, São Paulo has the largest port in Latin America and the largest offshore oil reservoir in Brazil, with a 600 km stretch of coastline with several marine mammal species. These human-made infrastructures affect the diversity, distribution, ecology, and the future of mammals in the state. Here, we answer five main questions: 1) What is the diversity of wild mammals in São Paulo state? 2) Where are they? 3) What is their positive and negative impact on human well-being? 4) How do mammals thrive in human-modified landscapes? 5) What is the future of mammals in the state? The state of São Paulo holds 255 species of native mammals, with four endemic species, two of them globally endangered. At least six species (two marsupials, Giant otter, Pampas deer, Brazilian dwarf brocket deer, and Giant armadillo) were extirpated from the state due to hunting and habitat loss. The intense human land use in the state forced many mammalian species to change their diet to cope with the intense fragmentation and agriculture. Large-scale monoculture has facilitated the invasion of exotic species such as wild boars (javali) and the European hare. Several "savanna-dwelling" species are expanding their ranges (Maned wolf, Brocket deer) over deforested areas and probably reflect changes towards a drier climate. Because the state has the largest road system, about 40,000 mammals from 33 species are killed per year in collisions causing an economic loss of 12 million dollars/year. The diversity of mammals is concentrated in the largest forest remnants of Serra do Mar and in the interior of the State, mainly in the regions of Ribeirão Preto and Jundiaí. Sampling gaps are concentrated throughout the interior of the state, particularly in the northwest region. Wild mammals play a fundamental role in many ecosystem services, but they can also be a concern in bringing new emergent diseases to humans. Although the taxonomy of mammals seems to be well known, we show that new species are continuously being discovered in the state. Therefore, continuous surveys using traditional and new technologies (eDNA, iDNA, drones), long-term population monitoring, investigation of the interface of human-wildlife conflict, and understanding of the unique ecosystem role played by mammals are future avenues for promoting sustainable green landscapes allied to human well-being in the state. The planting of forest or savanna corridors, particularly along with major river systems, in the plateau, controlling illegal hunting in the coastal areas, managing fire regimes in the Cerrado, and mitigating roadkill must be prioritized to protect this outstanding mammal diversity.

Resumo Os mamíferos são organismos carismáticos que desempenham um papel fundamental na função ecológica e nos serviços ecossistêmicos, como polinização, dispersão de sementes, ciclagem de nutrientes e controle de pragas. O Estado de São Paulo representa apenas 3% do território brasileiro, mas detém 33% da diversidade de mamíferos. A maior parte de seu território é dominado pela agricultura, pastagens e áreas urbanas que afetam diretamente a diversidade e a persistência dos mamíferos na paisagem. Além disso, São Paulo possui o maior porto da América Latina e o maior reservatório de petróleo costeiro do Brasil, com 600 km de extensão de litoral com diversas espécies de mamíferos marinhos. Essas infraestruturas afetam a diversidade, distribuição, ecologia e o futuro dos mamíferos no estado. Aqui, respondemos cinco perguntas principais: 1) Qual é a diversidade de mamíferos silvestres no Estado de São Paulo? 2) Onde eles ocorrem? 3) Qual é o seu impacto positivo e negativo no bem-estar humano? 4) Como os mamíferos persistem em paisagens modificadas pelo homem? 5) Qual é o futuro dos mamíferos no estado? O estado de São Paulo possui 255 espécies de mamíferos nativos, com quatro espécies endêmicas, duas delas globalmente ameaçadas de extinção. Pelo menos seis espécies (dois marsupiais, ariranha, veado-campeiro, veado-cambuta e tatu-canastra) foram extirpadas do estado devido à caça e perda de habitat. O intenso uso humano da terra no estado forçou muitas espécies de mamíferos a mudar sua dieta para lidar com a intensa fragmentação e agricultura. A monocultura em larga escala facilitou a invasão de espécies exóticas, como porcos selvagens (javaporco) e a lebre europeia. Várias espécies de áreas abertas estão expandindo suas áreas de distribuição (lobo-guará, veado-catingueiro) sobre áreas desmatadas e provavelmente refletem mudanças em direção a um clima mais seco. Como o estado possui o maior sistema rodoviário do Brasil, cerca de 40 mil mamíferos de 33 espécies são mortos por ano em colisões, causando um prejuízo econômico de 12 milhões de dólares/ano. A diversidade de mamíferos está concentrada nos maiores remanescentes florestais da Serra do Mar e no interior do Estado, principalmente nas regiões de Ribeirão Preto e Jundiaí. As lacunas amostrais estão concentradas em todo o interior do estado, principalmente na região noroeste. Os mamíferos silvestres desempenham um papel fundamental em muitos serviços ecossistêmicos, mas também podem ser uma preocupação em trazer novas doenças emergentes para as populações humanas. Embora a taxonomia de mamíferos pareça ser bem conhecida, mostramos que novas espécies estão sendo continuamente descobertas no estado. Portanto, pesquisas usando tecnologias tradicionais e novas (eDNA, iDNA, drones), monitoramento populacional de longo prazo, a investigação da interface do conflito homem-vida selvagem e a compreensão do papel único no ecossistema desempenhado pelos mamíferos são um caminho futuro para promover uma paisagem verde sustentável aliada ao bem-estar humano no estado. O plantio de corredores florestais ou de cerrado, principalmente junto aos principais sistemas fluviais, no planalto, o controle da caça ilegal nas áreas costeiras, o manejo dos regimes de fogo no Cerrado e a mitigação dos atropelamentos devem ser uma prioridade para proteger essa notável diversidade de mamíferos.

RESUMO

Knowledge of the reproductive biology of Bare-faced Curassows (BFC) from their natural habitats is very limited. Our study covers a two-and-a-half year breeding phenology on BFC in the northern Pantanal (Mato Grosso State, Brazil) with the main objective of collecting information on reproduction biology to contribute to future conservation management strategies of this cracid, which received a recent status of "High Conservation Priority". The study was conducted at the SESC Pantanal, Baía das Pedras, Mato Grosso, Brazil (16°29′55″S, 56°24′46″W), a private protected area of approximately 4,200 ha. Between July 2015 and December 2017, 37 sampling locations were monitored with camera traps placed in a regular grid with a spacing of 1 km. Offspring were detected at least once at 8 locations, namely, in March, April, and May 2016 and in June, July, October, and November 2017, always together with parent(s). Territorial overlap between different family groups was detected. The camera trap dataset was supplemented by data from Citizen Science Projects (i.e., eBird) and the Global Biodiversity Information Facility (GBIF). Based on feather developmental stages and body size, offspring were classified into different age classes. Age determination indicates that breeding occurs year-round in the northern Pantanal region, supported by eBird and GBIF data. The use of a grid-based design for future camera-trapping studies of BFCs is strongly recommended. Our study is of biological relevance for conservation management projects since data were collected in an area with low anthropogenic disturbance and intact ecosystem services.(AU)

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In a scenario where escalating human activities lead to several environmental changes and, consequently, affect mammal abundance and distribution, ß-diversity may increase due to differences among sites. Using the ecological uniqueness approach, we analyzed ß-diversity patterns of ground-dwelling mammal communities recorded through comprehensive camera trap monitoring within eight tropical forests protected areas in Mesoamerica and South America under variable landscape contexts. We aimed to investigate whether the contribution of single sites (LCBD) and single species (SCBD) to overall ß-diversity could be explained by community metrics and environmental variables, and by species metrics and biological traits, respectively. Total ß-diversity was also partitioned into species replacement and richness difference. We related LCBD to species richness, total relative abundance, functional indices, and environmental variables (tree basal area, protected area size, NDVI, and precipitation seasonality), and SCBD to species naïve occupancy, relative abundance, and morphoecological traits via beta regression. Our findings showed that LCBD was primarily explained by variation in species richness, rather than relative abundance and functional metrics. Protected area size and tree basal area were also important in explaining variation in LCBD. SCBD was strongly related to naïve occupancy and relative abundance, but not to biological traits, such as body mass, trophic energy level, activity cycle, and taxonomic category. Local ß-diversity was a result of species replacements and to a lesser extent differences in species richness. Our approach was useful in examining and comparing the ecological uniqueness among different sites, revealing the regional scale current status of mammal diversity. High LCBD values comprised sites embedded within smaller habitat extents, hosting lower tree basal areas, and harboring low species richness. SCBD showed that relatively ubiquitous species that occur at variable abundances across sites contributed most to ß-diversity.

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Domestic dogs (Canis familiaris) often cohabite at interfaces shared by humans and wildlife, interacting with wild canids as predators, prey, competitors and reservoirs of several multi-host pathogens, such as canid-borne micro and macro parasites that could impact on wildlife, livestock and public health. However, spatio-temporal patterns of indirect interactions as promoters of pathogen transfer between domestic and wild canids are largely unknown. In this study, we used camera traps to describe the activity patterns and habitat use of dogs, chilla (Lycalopex griseus) and culpeo (Lycalopex culpaeus) foxes and identify the local-scale factors that may affect the frequency of dog-fox interactions through an anthropization gradient of the Coquimbo region, Chile. We assessed local-scale variables that may predict the number of interactions between dogs and foxes, and compared the time interval between dog-culpeo and dog-chilla interactions. Our findings suggested that closeness to urbanized zones predicts the frequency of indirect interactions between dogs and foxes. We found higher number of dog-fox interactions (60 interactions) at a periurban site adjacent to two coastal towns (Tongoy and Guanaqueros), compared to other two more undisturbed sites (12 interactions) increasingly distanced from urbanized areas. We showed that dogs interacted more frequently with chilla foxes (57 interactions) than with culpeo foxes (15 interactions), and the first interaction type occurred almost exclusively at the periurban site, where dogs and chillas were more frequently detected than in the other sites. We detected a marked temporal segregation between dogs and foxes, but dog-chilla interactions resulted in shorter time intervals (2.5 median days) compared to dog-culpeo interactions (7.6 median days), suggesting a higher potential risk of pathogen spillover between the first species pairing. Based on previous studies, we suggest periurban zones may constitute a potential focus of pathogen exposure between dog and fox populations in the study area. Our research contributes to improving the knowledge on the spatio-temporal patterns of interspecific contact between invasive and native carnivores within the context of multi-host pathogen dynamics. Our outcomes will inform theoretical epidemiological models designed to predict and minimize the contact risk between domestic and threatened species, guiding effective control strategies at the wildlife-domestic interface.

RESUMO

Neotropical medium and large-bodied mammals are key elements in forest ecosystems, and protected areas are essential for their conservation. In Brazil, sustainable use protected areas (SU-PAs) allow both the conservation of biodiversity and the sustainable use of natural resources, especially in the Amazon region. However, SU-PAs usually suffer both internal and external pressures, and may be subject to variable degrees of defaunation. We sampled mammals using camera traps in two areas with different forest management and human occupation history in the Tapajós National Forest (TNF), in the western Amazon. Overall, we recorded a rich assemblage of medium and large-sized mammals, though both areas differed in species composition. The area with older and more intense human occupation and forest exploitation had more independent records of generalist species, while large species such as Tapirus terrestris and Panthera onca were recorded exclusively in the area with lower human occupation and no forest management. A comparison of our results with similar studies in other Amazonian sites suggests a reduction in the population size of large-bodied mammals, such as Tapirus terrestris and Tayassu pecari, likely in response to increased human activities. Local differences in human occupation within and between protected areas are common in the Amazon, demanding area-specific actions from public authorities to minimize impacts on wildlife caused by human activities. Specifically in TNF, we recommend long-term monitoring of the responses of mammals to human activities, to better subsidize conservation and management actions.(AU)

Mamíferos neotropicais de médio e grande porte são elementos chave em ecossistemas florestais, e unidades de conservação são essenciais para sua conservação. No Brasil, as unidades de conservação de uso sustentável (UC-US) permitem tanto a conservação da biodiversidade quanto a exploração sustentável dos recursos naturais, especialmente na Amazônia. Porém, as UC-US geralmente são afetadas por pressões internas e externas, e podem apresentar diferentes graus de defaunação. Amostramos mamíferos de médio e grande porte usando armadilhas fotográficas em duas áreas com distintos históricos de manejo e ocupação humana na Floresta Nacional do Tapajós (FNT), na Amazônia ocidental. Em geral, registramos uma rica assembleia de espécies de mamíferos de médio e grande porte, mas as duas áreas diferiram na composição de espécies. A área com ocupação humana mais intensa e antiga e exploração florestal apresentou mais registros independentes de espécies generalistas, enquanto espécies maiores, como Tapirus terrestris e Panthera onca, foram registradas exclusivamente na área com menor ocupação humana e sem manejo florestal. A comparação de nossos resultados com estudos similares em outros locais na Amazônia sugere uma redução no tamanho populacional de mamíferos de grande porte, como Tapirus terrestris e Tayassu pecari, provavelmente em resposta ao aumento das atividades humanas. Diferenças locais na ocupação humana dentro de e entre unidades de conservação são comuns na Amazônia, demandando ações específicas do poder público para minimizar impactos de atividades humanas sobre a fauna silvestre. Especificamente na FNT, recomendamos o monitoramento de longa duração das respostas de mamíferos às atividades humanas, para melhor embasar ações de conservação e manejo.(AU)ipt

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Neotropical medium and large-bodied mammals are key elements in forest ecosystems, and protected areas are essential for their conservation. In Brazil, sustainable use protected areas (SU-PAs) allow both the conservation of biodiversity and the sustainable use of natural resources, especially in the Amazon region. However, SU-PAs usually suffer both internal and external pressures, and may be subject to variable degrees of defaunation. We sampled mammals using camera traps in two areas with different forest management and human occupation history in the Tapajós National Forest (TNF), in the western Amazon. Overall, we recorded a rich assemblage of medium and large-sized mammals, though both areas differed in species composition. The area with older and more intense human occupation and forest exploitation had more independent records of generalist species, while large species such as Tapirus terrestris and Panthera onca were recorded exclusively in the area with lower human occupation and no forest management. A comparison of our results with similar studies in other Amazonian sites suggests a reduction in the population size of large-bodied mammals, such as Tapirus terrestris and Tayassu pecari, likely in response to increased human activities. Local differences in human occupation within and between protected areas are common in the Amazon, demanding area-specific actions from public authorities to minimize impacts on wildlife caused by human activities. Specifically in TNF, we recommend long-term monitoring of the responses of mammals to human activities, to better subsidize conservation and management actions.

Mamíferos neotropicais de médio e grande porte são elementos chave em ecossistemas florestais, e unidades de conservação são essenciais para sua conservação. No Brasil, as unidades de conservação de uso sustentável (UC-US) permitem tanto a conservação da biodiversidade quanto a exploração sustentável dos recursos naturais, especialmente na Amazônia. Porém, as UC-US geralmente são afetadas por pressões internas e externas, e podem apresentar diferentes graus de defaunação. Amostramos mamíferos de médio e grande porte usando armadilhas fotográficas em duas áreas com distintos históricos de manejo e ocupação humana na Floresta Nacional do Tapajós (FNT), na Amazônia ocidental. Em geral, registramos uma rica assembleia de espécies de mamíferos de médio e grande porte, mas as duas áreas diferiram na composição de espécies. A área com ocupação humana mais intensa e antiga e exploração florestal apresentou mais registros independentes de espécies generalistas, enquanto espécies maiores, como Tapirus terrestris e Panthera onca, foram registradas exclusivamente na área com menor ocupação humana e sem manejo florestal. A comparação de nossos resultados com estudos similares em outros locais na Amazônia sugere uma redução no tamanho populacional de mamíferos de grande porte, como Tapirus terrestris e Tayassu pecari, provavelmente em resposta ao aumento das atividades humanas. Diferenças locais na ocupação humana dentro de e entre unidades de conservação são comuns na Amazônia, demandando ações específicas do poder público para minimizar impactos de atividades humanas sobre a fauna silvestre. Especificamente na FNT, recomendamos o monitoramento de longa duração das respostas de mamíferos às atividades humanas, para melhor embasar ações de conservação e manejo.ipt

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Rapid assessments are the most common information source on biodiversity in the northwestern Amazon in Colombia due to limited resources and logistic constraints. These assessments are essential for decision-making on environmental policies in this region, that has been strongly impacted by the transformation of its natural ecosystems. Several local camera-trapping rapid assessments of medium and large-sized mammals (MLM) have been conducted in the Colombian Amazon, but they are difficult to compare. We analyzed information of 16 of these rapid assessments of MLM to provide the first list of MLM in the northwestern Amazon in Colombia. We also evaluated the accuracy of four estimators (ICE, Chao-2, Jackknife-1, and Jackknife-2), and the minimum sampling effort for the estimation of MLM richness in local surveys in the region. We report 26 species of MLM for the Colombian Amazon (between five and 13 species per locality), which is an underestimation of MLM richness in the region. The best estimator of MLM richness was the Jackknife-1, due to its precision and the lower influence of singletons. We recommend a minimum sampling effort of 350 camera trap-days. Although rapid assessments do not allow a robust estimation of MLM richness, they record the most common species (or core species) per locality and their abundance variation. The evaluation of the effect of habitat transformation on MLM and the estimation of population parameters of rare species require more intensive studies.(AU)

Las evaluaciones rápidas de biodiversidad son la fuente de información más común sobre biodiversidad en el noroccidente amazónico en Colombia debido a que los recursos y la logística son limitados. Estas evaluaciones son esenciales para tomar decisiones ambientales en esta área que ha sido impactada por la transformación de sus ecosistemas naturales. Diferentes evaluaciones locales rápidas con cámaras trampa de mamíferos medianos y grandes (MMG) se han realizado en el noroccidente Amazónico en Colombia, pero estas son difícilmente comparables. Nosotros recolectamos la información de 16 evaluaciones rápidas de MMG para proporcionar la primera lista de MMG del noroccidente amazónico en Colombia. Adicionalmente, evaluamos la precisión de cuatro estimadores (ICE, Chao 2, Jackknife 1 y Jackknife 2) y el esfuerzo mínimo de muestreo para la estimación de la riqueza de MMG en estudios locales en esa región. Reportamos 26 especies de MMG para la Amazonía colombiana (entre cinco y 13 especies por localidad), lo que es uns subestimación de la riqueza de MMG en la región. El mejor estimador para este tipo de estudios fue Jackknife 1, debido a su precisión y la baja influencia de singletons. Recomendamos un esfuerzo mínimo de muestreo de 350 cámaras trampa-día. Aunque las evaluaciones rápidas no proveen una estimación robusta de la riqueza de MMG, estas evaluaciones registran las especies más comunes (especies core) y la variación en su abundancia por localidad. Es necesario un mayor esfuerzo de muestreo para evaluar el efecto de la transformación del hábitat sobre los MMG, en especial sobre los parámetros poblacionales de las especies raras.(AU)

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Temporal niche shifts can shape predator-prey interactions by enabling predator avoidance, enhancing feeding success, and reducing competition among predators. Using a community-based conservation approach, we investigated temporal niche partitioning of mammalian predators and prey across 12 long-term camera trap surveys in the Pacific slope and Talamanca Cordillera of Costa Rica. Temporal overlap and segregation were investigated between predator-prey and predator-predator pairs using overlap analysis, circular statistics, and relative abundance after accounting for differences in habitat, season, and human impact among sites. We made the assumption that predators select abundant prey and adjust their activity to maximize their temporal overlap, thus we predicted that abundant prey with high overlap would be preferred prey species for that predator. We also predicted that similar-sized pairs of predator species with the greatest potential for competitive interactions would have the highest temporal segregation. Our results supported the existence of temporal niche separation among the eight species of predators-the smaller Leopardus felids (ocelot, margay, oncilla) were primarily nocturnal, the largest felids (jaguar and puma) and coyote were cathemeral, and the smaller jaguarundi and tayra were mostly diurnal. Most prey species (67%) were primarily nocturnal versus diurnal or cathemeral (33%). Hierarchical clustering identified relationships among species with the most similar activity patterns. We discuss the primary prey and competitor species predicted for each of the eight predators. Contrary to our prediction, the activity pattern of similar-sized intraguild competitors overlapped more than dissimilar-sized competitors, suggesting that similar-sized predators are hunting the same prey at the same time. From this we conclude that prey availability is more important than competition in determining circadian activity patterns of Neotropical predators. Our results indicate the presence of a delicate balance of tropical food webs that may be disrupted by overhunting, leading to a depauperate community consisting of ubiquitous generalists and endangered specialists. With Central America a hotspot for hunting-induced "empty forests," community-based conservation approaches may offer the best road to reduce illegal hunting and maintain the biodiversity and community structure of tropical forest systems.

Los cambios temporales de nicho pueden amoldar las interacciones predador-presa al permitir a la presa evadir los predadores, mejorar la eficacia de la alimentación y reducir la competición entre predadores. Mediante muestreos con cámaras trampa en 12 sitios de la pendiente del Pacífico y la Cordillera de Talamanca de Costa Rica, investigamos la división temporal de los nichos de mamíferos predadores y presas usando un enfoque de conservación basado en la comunidad. Investigamos la superposición y segregación temporal entre pares predador-presa y predador-predador utilizando análisis de superposición, estadísticas circulares y abundancia relativa, teniendo en cuenta diferencias de hábitat, estacionales y de impacto humano entre los sitios. Asumimos que los predadores seleccionan presas abundantes y ajustan su actividad para maximizar su superposición temporal con éstas; por lo tanto, predijimos que una presa abundante con alta superposición sería una especie de presa preferida para ese predador. También predijimos que pares de especies de predadores de tamaño similar con el mayor potencial para interacciones competitivas tendrían la mayor segregación temporal. Nuestros resultados respaldaron la existencia de una separación temporal de nicho entre las ocho especies de predadores­determinamos que los felinos más pequeños del género Leopardus (manigordo, caucel, tigrillo) son principalmente nocturnos, los felinos más grandes (jaguar y puma) y el coyote son catemerales, y los jaguarundi y tayra más pequeños son principalmente diurnos. La mayoría de las especies de presas (67%) son principalmente nocturnas versus diurnas o catemerales (33%). Mediante análisis de agrupación jerárquica, identificamos relaciones entre especies con los patrones de actividad más similares. Para cada uno de los predadores discutimos las presas primarias predichas y las especies competidoras. Contrario a nuestra predicción, el patrón de actividad de los predadores intragremios de tamaño similar se superpone más que el de los competidores de distinto tamaño, lo que indica que los predadores de tamaño similar están cazando la misma presa y están activos al mismo tiempo. De esto concluimos que la disponibilidad de presas es más importante que la competición en cuanto a determinar los patrones de actividad circadiana de los predadores neotropicales. Nuestros resultados revelan que el delicado equilibrio de las redes tróficas tropicales puede ser interferido por la caza excesiva, lo que lleva a una comunidad depauperada compuesta por generalistas ubicuos y especialistas en peligro de extinción. Con América Central como un centro de "bosques vacíos" inducidos por la caza, los enfoques de conservación basados en la comunidad pueden ofrecer el mejor camino para reducir la caza ilegal, y mantener la biodiversidad y estructura ecológica comunitaria de los sistemas forestales tropicales.

RESUMO

The Andean bear (Tremarctos ornatus) population density and relative abundance within the Chingaza Massif were assessed between September 2015 and May 2016. One hundred seventeen (117) camera traps were installed at 9 grids: 13 cameras per grid, each camera separated 750 m from the other; the sampling effort was 17,057 days-trap. Two thousand seven hundred eighty-four (2,784) native fauna records were obtained, 1,456 corresponding to mammals, 183 records for Andean bear specimens, 158 of them independent bear records (at least one hour between records), and 106 effective-independent bear records (also permitting individual recognition). Fifty-seven (57) Andean bear individuals were identified according to key external morphological features. Sixteen (16) adults were recaptured (12 males and 4 females), with a maximum mean distance of 27.22 km. Bears population density was 2.9 bears per 100 km². Based on this density and the buffer area of the sampling grids, we estimated an overall number of 122 bears in 4,215.15 km². The estimated density is the first for the species in Colombia and the lowest regarding previous reports from other countries. Thus, it is necessary to better understand how integral habitat quality and the anthropic impacts on habitat quality, availability, and connectivity may affect the Andean bear population densities in Colombia, as a useful tool for assessing populations` state and focus future conservation actions.(AU)

Assuntos

RESUMO

The Andean bear (Tremarctos ornatus) population density and relative abundance within the Chingaza Massif were assessed between September 2015 and May 2016. One hundred seventeen (117) camera traps were installed at 9 grids: 13 cameras per grid, each camera separated 750 m from the other; the sampling effort was 17,057 days-trap. Two thousand seven hundred eighty-four (2,784) native fauna records were obtained, 1,456 corresponding to mammals, 183 records for Andean bear specimens, 158 of them independent bear records (at least one hour between records), and 106 effective-independent bear records (also permitting individual recognition). Fifty-seven (57) Andean bear individuals were identified according to key external morphological features. Sixteen (16) adults were recaptured (12 males and 4 females), with a maximum mean distance of 27.22 km. Bears population density was 2.9 bears per 100 km². Based on this density and the buffer area of the sampling grids, we estimated an overall number of 122 bears in 4,215.15 km². The estimated density is the first for the species in Colombia and the lowest regarding previous reports from other countries. Thus, it is necessary to better understand how integral habitat quality and the anthropic impacts on habitat quality, availability, and connectivity may affect the Andean bear population densities in Colombia, as a useful tool for assessing populations` state and focus future conservation actions.

Assuntos

RESUMO

Abstract The Andean bear (Tremarctos ornatus) population density and relative abundance within the Chingaza Massif were assessed between September 2015 and May 2016. One hundred seventeen (117) camera traps were installed at 9 grids: 13 cameras per grid, each camera separated 750 m from the other; the sampling effort was 17,057 days-trap. Two thousand seven hundred eighty-four (2,784) native fauna records were obtained, 1,456 corresponding to mammals, 183 records for Andean bear specimens, 158 of them independent bear records (at least one hour between records), and 106 effective-independent bear records (also permitting individual recognition). Fifty-seven (57) Andean bear individuals were identified according to key external morphological features. Sixteen (16) adults were recaptured (12 males and 4 females), with a maximum mean distance of 27.22 km. Bears population density was 2.9 bears per 100 km². Based on this density and the buffer area of the sampling grids, we estimated an overall number of 122 bears in 4,215.15 km². The estimated density is the first for the species in Colombia and the lowest regarding previous reports from other countries. Thus, it is necessary to better understand how integral habitat quality and the anthropic impacts on habitat quality, availability, and connectivity may affect the Andean bear population densities in Colombia, as a useful tool for assessing populations` state and focus future conservation actions.

RESUMO

Albinism is a genetic condition that results in total hypopigmentation of the eyes, fur, skin, hair, scales, and feathers of an organism. Albinism might result in a selective disadvantage for affected animals. Cases of albinism have been previously recorded in Neotropical vertebrates, such as reptiles, mammals, birds, and fish. However, observing albinism in a wild population is still considered to be a rare event. This paper reports a unique case of complete albinism in a red-brocket deer (Mazama americana) living in the Brazilian Amazon rainforest. The individual was observed within the Biological Reserve of Pará State, one of the most deforested regions of the Brazilian Amazon. The survival of the albino red-brocket deer in the wild can be related to mechanisms of apostatic selection, which theorize the survival of individual prey animals whose mutations make them less likely to be attacked by predators. In other words, the more different a prey animal is from others, the less likely it will be targeted by predators. The high abundance prey animals within the Biological Reserve of Tapirapé seems to support this prediction. This report exemplifies the importance of monitoring the biodiversity and promoting the conservation of favorable habitats to support species multiplicity in highly fragmented regions, as in the Brazilian Amazon.

Assuntos

RESUMO

Albinism is a genetic condition that results in total hypopigmentation of the eyes, fur, skin, hair, scales, and feathers of an organism. Albinism might result in a selective disadvantage for affected animals. Cases of albinism have been previously recorded in Neotropical vertebrates, such as reptiles, mammals, birds, and fish. However, observing albinism in a wild population is still considered to be a rare event. This paper reports a unique case of complete albinism in a red-brocket deer (Mazama americana) living in the Brazilian Amazon rainforest. The individual was observed within the Biological Reserve of Pará State, one of the most deforested regions of the Brazilian Amazon. The survival of the albino red-brocket deer in the wild can be related to mechanisms of apostatic selection, which theorize the survival of individual prey animals whose mutations make them less likely to be attacked by predators. In other words, the more different a prey animal is from others, the less likely it will be targeted by predators. The high abundance prey animals within the Biological Reserve of Tapirapé seems to support this prediction. This report exemplifies the importance of monitoring the biodiversity and promoting the conservation of favorable habitats to support species multiplicity in highly fragmented regions, as in the Brazilian Amazon.(AU)

Assuntos

RESUMO

Las cámaras trampa constituyen una herramienta de gran utilidad para el estudio de vertebrados terrestres. Con el objetivo de evaluar la utilidad del fototrampeo para el estudio de la avifauna, se analizaron los registros obtenidos, entre julio 2015 y julio 2016, por cámaras trampa instaladas en 12 puntos con aguadas artificiales de la Estancia Montania, departamento de Boquerón, Paraguay. Se determinó la riqueza, composición y tasa de captura registrada en bosques xerofíticos y pasturas exóticas. Se comparó la riqueza y composición de aves detectada mediante cámaras trampa con la obtenida a través de listas Mackinnon. Mediante fototrampeo, fueron registradas 74 especies, pertenecientes a 30 familias y 16 órdenes. El bosque xerofítico y la pastura exótica poseen un 52.7 % de similitud en cuanto a la composición de las especies. Las especies registradas con mayor frecuencia fueron: Leptotila verreauxi (16.14 %), Ortalis canicollis (14.28 %) y Furnarius cristatus (11.39 %). Las cámaras trampa resultaron efectivas para el registro del 33 % de las especies identificadas a través de listas Mackinnon, y adicionaron dos especies. Por ello, resultan apropiadas para complementar métodos basados en la observación directa, particularmente para el registro de especies cinegéticas del ecosistema chaqueño pertenecientes a los órdenes Tinamiformes y Columbiformes.

Camera trap as a sampling method for Paraguayan Dry Chaco birds: a comparison with auditory and visual methods. Camera trap techniques are widely used for the study of mammals, but also enable investigation of other groups, such as birds. In order to evaluate the usefulness of camera trapping for the study of avifauna, we analyzed the records obtained from 12 camera traps installed between July 2015 and July 2016, near artificial water sources in Estancia Montania, Boquerón Department, Paraguay. Four of these sites were associated with xerophytic forests and eight with exotic pastures. The richness, composition and capture rate recorded in both ecosystems were determined. We compared the richness and composition of birds detected by camera traps with those obtained through auditory and visual methods. Through camera trapping, 74 species of birds were recorded, belonging to 30 families and 16 orders. The xerophytic forest and the exotic pasture have a 52.7 % similarity in species composition. With regard to capture rates, the most frequently recorded species were: Leptotila verreauxi (16.14 %), Ortalis canicollis (14.28 %) and Furnarius cristatus (11.39 %). The camera traps were effective in detecting 33% of the species identified in the area based on direct and auditory observation sampling techniques, and added two species not detected by direct methods. For this reason, camera trapping is appropriate to complement methods based on direct observation, particularly for monitoring hunted species of the Chaco ecosystem belonging to Tinamiform and Columbiform species. Due to the non-invasive nature of the technique, it constitutes an efficient method for addressing ethological studies of terrestrial species.

RESUMO

The Colombian Orinoquia region is characterized by a high diversity of mammals, which is associated with complex ecosystems that include large extensions of Neotropical savannas (known locally as Llanos Orientales). Despite accelerated anthropogenic transformations in savanna ecosystems, the knowledge to design effective conservation strategies, such as the distribution of mammal assemblages, is still lacking for this region. In this paper, we evaluate if assemblages of medium and large mammals (i.e., species richness, relative abundance and the contribution of the different trophic guilds) are homogeneous across the Colombian Llanos by comparing three savanna ecosystems: floodplains savannas associated with an Andean river, aeolian floodplains savannas and highland savannas. After a sampling effort of 3,150 camera trap/days, we recorded 16 mammal species from the three savanna ecosystems. We compared the three assemblages and their constituent trophic guilds by ANOSIM and SIMPER non-parametric permutation tests. The three assemblages differed in composition, structure and trophic guilds. The floodplains savannas, associated to an Andean river, present the highest diversity, contrastingly, the high-plain associated with the Guyanese Shield presents the lowest diversity. This pattern could be explained due to the greatest floristic diversity, complex vegetation structure and more fertile soils present in the riparian forests of the floodplains savannas, despite being the most anthropogenically transformed. The carnivores were the most variable category and herbivores were the most abundant. Our results show that the diversity of medium and large mammals is heterogeneously distributed in the Colombian Llanos. Therefore, it is necessary to implement targeted conservation strategies according to the characteristics, local fragility of each ecosystem in the territory and each species response by local conditions.(AU)

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