The bush dog Speothos venaticus is a highly social Neotropical canid categorized globally on the IUCN Red List as Near Threatened, as Vulnerable in Brazil and as Critically Endangered in Minas ...Gerais, south-eastern Brazil, and the Atlantic Forest as a result of human pressure. As part of the monitoring of this mammal, during January 2019–March 2020 we placed one camera trap in each of 22 forest fragments in various landscapes in 15 municipalities in the state of Minas Gerais and one municipality in the state of Rio de Janeiro. On average, each camera trap was active for 4.3 months in each fragment. In a total of 2,856 trap-days we obtained the first record of S. venaticus in south-eastern Minas Gerais, c. 2 km from Serra de Santa Rita Mítzi Brandão Biological Reserve. This is the northernmost record of S. venaticus in the Atlantic Forest and highlights the importance of forest remnants in a fragmented landscape for this species. Further monitoring of this area should be a priority, to increase knowledge regarding the distribution of this species and for developing conservation strategies appropriate to these fragmented landscapes.
1. Niche conservatism, i.e. the retention of a species' fundamental niche through evolutionary time, is cornerstone for biological invasion assessments. The fact that species tend to maintain their ...original climate niche allows predictive maps of invasion risk to anticipate potential invadable areas. Unravelling the mechanisms driving niche shifts can shed light on the management of invasive species. 2. Here, we assessed niche shifts in one of the world's worst invasive species: the wild boar Sus scrofa. We also predicted potential invadable areas based on an ensemble of three ecological niche modelling methods, and evaluated the performance of models calibrated with native vs. pooled (native plus invaded) species records. By disentangling the drivers of change on the exotic wild boar population's niches, we found strong evidence for niche conservatism during biological invasion. 3. Ecological niche models calibrated with both native and pooled range records predicted convergent areas. Also, observed niche shifts are mostly explained by niche unfilling, i.e. there are unoccupied areas in the exotic range where climate is analogous to the native range. 4. Niche unfilling is expected as result of recent colonization and ongoing dispersal, and was potentially stronger for the Neotropics, where a recent wave of introductions for pig-farming and game-hunting has led to high wild boar population growth rates. The invasive potential of wild boar in the Neotropics is probably higher than in other regions, which has profound management implications if we are to prevent their invasion into species-rich areas, such as Amazonia, coupled with expansion of African swine fever and possibly great economic losses. 5. Although the originally Eurasian-wide distribution suggests a pre-adaptation to a wide array of climates, the wild boar world-wide invasion does not exhibit evidence of niche evolution. The invasive potential of the wild boar therefore probably lies on the reproductive, dietary and morphological characteristics of this species, coupled with behavioural thermoregulation.
The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation ...during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods.
The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the ...diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.
The objective of our work was to verify the value of the vegetation corridor in the conservation of small mammals in fragmented tropical landscapes, using a model system in the southeastern Minas ...Gerais. We evaluated and compared the composition and structure of small mammals in a vegetation corridor, forest fragments and a coffee matrix. A total of 15 species were recorded, and the highest species richness was observed in the vegetation corridor (13 species), followed by the forest fragments (10) and the coffee matrix (6). The absolute abundance was similar between the vegetation corridor and fragments (F = 22.94; p = 0.064), and the greatest differences occurred between the vegetation corridor and the matrix (F = 22.94; p = 0.001) and the forest fragments and the matrix (F = 22.94; p = 0.007). Six species showed significant habitat preference possibly related to the sensitivity of the species to the forest disturbance. Marmosops incanus was the species most sensitive to disturbance; Akodon montensis, Cerradomys subflavus, Gracilinanus microtarsus and Rhipidomys sp. displayed little sensitivity to disturbance, with a high relative abundance in the vegetation corridor. Calomys sp. was the species least affected by habitat disturbance, displaying a high relative abundance in the coffee matrix. Although the vegetation corridors are narrow (4 m width), our results support the hypothesis in which they work as a forest extension, share most species with the forest fragment and support species richness and abundance closer to forest fragments than to the coffee matrix. Our work highlights the importance and cost-effectiveness of these corridors to biodiversity management in the fragmented Atlantic Forest landscapes and at the regional level.
Resumo Apresenta-se uma análise comparativa com base em dados médios mensais de precipitação acumulada e temperaturas máximas e mínimas registradas durante o período 2000-2019 pelas estações ...meteorológicas convencionais e automáticas existentes no Brasil. Foi avaliada a exatidão da localização das estações (coordenadas geográficas) fornecida pelo Instituto Nacional de Meteorologia (INMET), foi comparada gráfica e estatisticamente a informação fornecida por estações homônimas, foi correlacionada esta informação com variáveis independentes (elevação e latitude no caso das temperaturas e informação de satélite da Tropical Rainfall Measuring Mission -TRMM 3B43- no caso da precipitação), e foi avaliada a consistência da informação fornecida pelas estações comparada com os dados das cinco estações geograficamente mais próximas, através de interpolações espaciais baseadas em distancias inversas ponderadas sob um esquema de Jaccknife. Ainda que a informação fornecida ambos os tipos de estações podem ter boa concordância em muitos casos, existem incongruências que em alguns casos podem ser muito marcadas. Tais diferenças podem ser atribuídas tanto a erros sistemáticos como aleatórios, de origem indeterminada. Ambos conjuntos de dados tem problemas, mas a evidência avaliada sugere que as estações convencionais fornecem dados de precipitação um pouco mais confiáveis, enquanto que as automáticas são mais consistentes em relação a informação de temperaturas.
Abstract A comparative analysis is presented based, on one side, mean monthly accumulated precipitation and, on the other, maximum and minimum monthly mean temperatures, recorded during the period 2000-2019 by conventional and automatic weather stations existing in Brazil. The accuracy of the location of the stations (geographic coordinates) provided by the National Institute of Meteorology (INMET) was evaluated, comparing graphically and statistically the information provided by homonymous stations, this information was correlated with independent variables (elevation and latitude in the case of temperatures, and satellite information from the Tropical Rainfall Measuring Mission -TRMM 3B43-, in the case of precipitation), and evaluate the consistency of the information provided by the stations compared with data from the five stations geographically closest through spatial interpolations based on inverse-distance weighted under a Jaccknife scheme. Although the information provided by both types of stations may have good agreement in many cases, there are incongruities that in some cases can be very marked. Such differences can be attributed to both systematic and random errors, of indeterminate origin. Both data sets have problems, but the evidence evaluated suggests that conventional stations provide slightly more reliable precipitation data, while automatic ones are more consistent with regards to temperature information.
The Cerrado domain and its biodiversity has suffered several anthropogenic influences. Our objective was to evaluate the influence of biotic and anthropic variables on the mammal community in a ...protected area in the Cerrado-Caatinga ecotone. For this we sampled the mammals using camera traps (4,072 days/trap) for 16 months. We used generalized mixed linear models (GLMM) with model selection via Akaike's Information Criteria corrected for small sample size (AICc) to assess the influence of variables on richness, abundance and functional groups of mammals. We made a total of 663 photographic records of 16 species of medium and large mammals. The richness and number of mammals was negatively influenced by the distance to human settlements while carnivores were not affected by any of the variables evaluated, herbivores and generalists were more common in areas closer from human habitation. Despite the presence of large areas of native vegetation, our results show that there is a dominance of common and generalist species. The protected area is vulnerable to different sources of human pressure and the design and implementation of a management plan can be a key tool for protecting biodiversity and regulating the use of natural resources by local communities.
Canine visceral leishmaniasis is an important zoonosis in Brazil. However, infection patterns are unknown in some scenarios such as rural settlements around Atlantic Forest fragments. Additionally, ...controversy remains over risk factors, and most identified patterns of infection in dogs have been found in urban areas. We conducted a cross-sectional epidemiological survey to assess the prevalence of leishmaniasis in dogs through three different serological tests, and interviews with owners to assess features of dogs and households around five Atlantic Forest remnants in southeastern Brazil. We used Generalized Linear Mixed Models and Chi-square tests to detect associations between prevalence and variables that might influence Leishmania infection, and a nearest neighbor dispersion analysis to assess clustering in the spatial distribution of seropositive dogs. Our findings showed an average prevalence of 20% (ranging from 10 to 32%) in dogs. Nearly 40% (ranging from 22 to 55%) of households had at least one seropositive dog. Some individual traits of dogs (height, sterilization, long fur, age class) were found to positively influence the prevalence, while some had negative influence (weight, body score, presence of ectoparasites). Environmental and management features (number of cats in the households, dogs with free-ranging behavior) also entered models as negative associations with seropositivity. Strong and consistent negative (protective) influences of the presence of chickens and pigs in dog seropositivity were detected. Spatial clustering of cases was detected in only one of the five study sites. The results showed that different risk factors than those found in urban areas may drive the prevalence of canine leishmaniasis in farm/forest interfaces, and that humans and wildlife risk infection in these areas. Domestic dog population limitation by gonadectomy, legal restriction of dog numbers per household and owner education are of the greatest importance for the control of visceral leishmaniasis in rural zones near forest fragments.
The interaction between ecology and evolution, particularly with regard to speciation processes, remains a main topic of scientific research. Andean hummingbirds have undergone a remarkable ...radiation, with many species exhibiting patchy distributions and, in some cases, taxonomic controversy. An example is the sapphire‐vented puffleg Eriocnemis luciani; ssp. baptistae, luciani and meridae, which some authors merge with the coppery‐naped puffleg E. sapphiropygia; ssp. catharina and sapphiropygia. Each group is distributed either north or south from the Huancabamba Depression, the major biogeographical barrier within the tropical Andes. We investigated whether these subspecies share some niche characteristics despite their geographical separation and determined their meaning in the context of the speciation process of trochilids in the tropical Andes. For each subspecies, we performed geographical predictions and paired tests of niche conservatism in environmental space. Geographical predictions included separate regions for subspecies catharina and sapphiropygia, while the predicted regions for subspecies luciani and baptistae greatly overlapped. The E. l. luciani model predicted a single pixel near to the potential area of E. l. meridae, known only from a unique, old record. Subspecies luciani and baptistae exhibited the greatest niche overlap among the pairs of taxa for most variables. However, our results clearly indicated niche divergence for the four members of the E. luciani–sapphiropygia complex, independent of the similarities or slight dissimilarities in their respective backgrounds, indicating that other forces in addition to variation in environmental parameters, such as natural selection or genetic drift, are driving the radiation of these hummingbirds. This finding coincides with the unusually high speciation rates reported for Andean hummingbirds. Thus, the currently accepted taxonomy within the E. luciani–sapphiropygia complex may be even more convoluted than indicated by previous studies. Hence, the results of our study are a wakeup call to include the exploration of lineage diversification in biodiversity‐related efforts.
We surveyed, with the aid of camera traps, medium-sized and large terrestrial mammals in 8 patches of semideciduous Atlantic Forest near the city of Alfenas, Minas Gerais, Brazil. We recorded species ...occurrence using 2 camera traps per fragment, which were simultaneously active for 2 months each. We recorded 16 species, plus a species of armadillo that we were unable to identify to genus. The rarefaction curve tended to stabilize, evidencing the efficacy of our methods. The species richness was similar or higher to other surveys carried out in remnants of seasonal semideciduous Atlantic Forest or transitional areas. However, such seemingly high richness in a severely degraded and fragmented region, including large carnivores and endangered species, hides a wide variation in richness among fragments. This calls for urgent actions to improve the landscape for these animals to ensure their survival in the long term, as some populations are probably not viable in the long run.
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