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A key challenge for conservation biology in the Neotropics is to understand how deforestation affects biodiversity at various levels of landscape fragmentation. Addressing this challenge requires expanding the coverage of known biodiversity data, which remain to date restricted to a few well-surveyed regions. Here, we assess the sampling coverage and biases in biodiversity data on fruit-feeding butterflies at the Brazilian Atlantic Forest, discussing their effect on our understanding of the relationship between forest fragmentation and biodiversity at a large-scale. We hypothesize that sampling effort is biased towards large and connected fragments, which occur jointly in space at the Atlantic forest. We used a comprehensive dataset of Atlantic Forest fruit-feeding butterfly communities to test for sampling biases towards specific geographical areas, climate conditions and landscape configurations. We found a pattern of geographical aggregation of sampling sites, independently of scale, and a strong sampling bias towards large and connected forest fragments, located near cities and roads. Sampling gaps are particularly acute in small and disconnected forest fragments and rare climate conditions. In contrast, currently available data can provide a fair picture of fruit-feeding butterfly communities in large and connected Atlantic Forest remnants. Biased data hamper the inference of the functional relationship between deforestation and biodiversity at a large-scale, since they are geographically clustered and have sampling gaps in small and disconnected fragments. These data are useful to inform decision-makers regarding conservation efforts to curb biodiversity loss in the Atlantic Forest. Thus, we suggest to expand sampling effort to small and disconnected forest fragments, which would allow more accurate evaluations of the effects of landscape modification.

Conservationists often have difficulty obtaining financial and social support for protected areas that do not demonstrate their benefits for society. Therefore, ecosystem services have gained importance in conservation science in the last decade, as these services provide further justification for appropriate management and conservation of natural systems. We used InVEST software and a set of GIS procedures to quantify, spatialize and evaluated the overlap between ecosystem services-carbon stock and sediment retention-and a biodiversity proxy-habitat quality. In addition, we proposed a method that serves as an initial approach of a priority areas selection process. The method considers the synergism between ecosystem services and biodiversity conservation. Our study region is the Iron Quadrangle, an important Brazilian mining province and a conservation priority area located in the interface of two biodiversity hotspots, the Cerrado and Atlantic Forest biomes. The resultant priority area for the maintenance of the highest values of ecosystem services and habitat quality was about 13% of the study area. Among those priority areas, 30% are already within established strictly protected areas, and 12% are in sustainable use protected areas. Following the transparent and highly replicable method we proposed in this study, conservation planners can better determine which areas fulfill multiple goals and can locate the trade-offs in the landscape. We also gave a step towards the improvement of the habitat quality model with a topography parameter. In areas of very rugged topography, we have to consider geomorfometric barriers for anthropogenic impacts and for species movement and we must think beyond the linear distances. Moreover, we used a model that considers the tree mortality caused by edge effects in the estimation of carbon stock. We found low spatial congruence among the modeled services, mostly because of the pattern of sediment retention distribution.

The effects of streets on biodiversity is an important aspect of urban ecology, but it has been neglected worldwide. Several vegetation attributes (e.g. street tree density and diversity) have important effects on biodiversity and ecological processes. In this study, we evaluated the influences of urban vegetation-represented by characteristics of street trees (canopy size, proportion of native tree species and tree species richness)-and characteristics of the landscape (distance to parks and vegetation quantity), and human impacts (human population size and exposure to noise) on taxonomic data and functional diversity indices of the bird community inhabiting streets. The study area was the southern region of Belo Horizonte (Minas Gerais, Brazil), a largely urbanized city in the understudied Neotropical region. Bird data were collected on 60 point count locations distributed across the streets of the landscape. We used a series of competing GLM models (using Akaike's information criterion for small sample sizes) to assess the relative contribution of the different sets of variables to explain the observed patterns. Seventy-three bird species were observed exploiting the streets: native species were the most abundant and frequent throughout this landscape. The bird community's functional richness and Rao's Quadratic Entropy presented values lower than 0.5. Therefore, this landscape was favoring few functional traits. Exposure to noise was the most limiting factor for this bird community. However, the average size of arboreal patches and, especially the characteristics of street trees, were able to reduce the negative effects of noise on the bird community. These results show the importance of adequately planning the urban afforestation process: increasing tree species richness, preserving large trees and planting more native trees species in the streets are management practices that will increase bird species richness, abundance and community functional aspects and consequently improve human wellbeing and quality of life.

Theoretical and empirical studies demonstrate that the total amount of forest and the size and connectivity of fragments have nonlinear effects on species survival. We tested how habitat amount and configuration affect understory bird species richness and abundance. We used mist nets (almost 34,000 net hours) to sample birds in 53 Atlantic Forest fragments in southeastern Brazil. Fragments were distributed among 3 10,800-ha landscapes. The remaining forest in these landscapes was below (10% forest cover), similar to (30%), and above (50%) the theoretical fragmentation threshold (approximately 30%) below which the effects of fragmentation should be intensified. Species-richness estimates were significantly higher (F = 3715, p = 0.00) where 50% of the forest remained, which suggests a species occurrence threshold of 30—50% forest, which is higher than usually occurs (<30%). Relations between forest cover and species richness differed depending on species sensitivity to forest conversion and fragmentation. For less sensitive species, species richness decreased as forest cover increased, whereas for highly sensitive species the opposite occurred. For sensitive species, species richness and the amount of forest cover were positively related, particularly when forest cover was 30—50%. Fragment size and connectivity were related to species richness and abundance in all landscapes, not just below the 30% threshold. Where 10% of the forest remained, fragment size was more related to species richness and abundance than connectivity. However, the relation between connectivity and species richness and abundance was stronger where 30% of the landscape was forested. Where 50% of the landscape was forested, fragment size and connectivity were both related to species richness and abundance. Our results demonstrated a rapid loss of species at relatively high levels of forest cover (30—50%). Highly sensitive species were 3-4 times more common above the 30—50% threshold than below it; however, our results do not support a unique fragmentation threshold. Estudios teóricos y empíricos demuestran que la cantidad total de bosque y el tamaño y la conectividad de los fragmentos tienen efectos no lineales sobre la supervivencia de especies. Probamos el efecto de la cantidad y configuración de hábitat sobre la riqueza y abundancia de especies de aves de sotobosque. Utilizamos redes de niebla (casi 34,000 horas red) para muestrear aves en 53 fragmentos del Bosque del Atlántico en el sureste de Brasil. Los fragmentos se distribuyeron en tres paisajes de 10,800 ha. El bosque remanente en estos paisajes era menor (10% cobertura forestal), similar (30%) y superior (50%) al umbral de fragmentación teórico (aproximadamente 30%) por debajo del cual se intensifican los efectos de la fragmentación. Las estimaciones de riqueza de especies fueron significativamente mayores (F = 3715, p = 0.00) donde permanecía 50% del bosque, lo que sugiere un umbral de ocurrencia de especies de 30—50% que es mayor a lo que ocurre usualmente (<30%). Las relaciones entre la cobertura de bosque y la riqueza de especies difirieron dependiendo de la sensibilidad de la especie a la conversión y fragmentación del bosque. Para especies menos sensibles, la riqueza de especies decreció a medida que incrementó la cobertura de bosque, mientras que ocurrió lo contrario para especies altamente sensibles. Para especies sensibles, la riqueza de especies y la cantidad de cobertura de bosque estuvieron relacionados positivamente, particularmente cuando la cobertura del bosque fue 30—50%. El tamaño del fragmento y la conectividad se relacionaron con la riqueza y abundancia de especies en todos los paisajes, no solo debajo del umbral de 30%. Cuando permanecía 10% del bosque, el tamaño del fragmento estaba más relacionado con la riqueza y abundancia de especies que la conectividad. Sin embargo, la relación entre la conectividad y la riqueza y abundancia de especies fue mayor donde 30% del paisaje tenía bosques. Donde 50% del paisaje tenía bosques, el tamaño del fragmento y la conectividad se relacionaron con la riqueza y abundancia de especies. Nuestros resultados demostraron una pérdida rápida de especies en niveles relativamente altos de cobertura forestal (30—50%). Especies altamente sensibles fueron 3—4 veces más comunes por encima del umbral de 30—50% que por debajo de él; sin embargo, nuestros resultados no sustentan un umbral de fragmentación único.

Despite its negative impacts on the environment and biodiversity, tree plantations can contribute to biodiversity conservation in fragmented landscapes, as they harbor many native species. In this study, we investigated the impact of Eucalyptus plantations on the taxonomic and functional diversity of ant communities, comparing ant communities sampled in managed and unmanaged (abandoned for 28 years) Eucalyptus plantations, and native Atlantic rain forests. Eucalyptus plantations, both managed and unmanaged, reduced the functional diversity and increased the similarity between ant communities leading to functional homogenization. While communities in managed plantations had the lowest values of both taxonomic and functional ant diversities, ant communities from unmanaged plantations had similar values of species richness, functional redundancy and Rao’s Q compared to ant communities from forest patches (although functional richness was lower). In addition, communities in unmanaged Eucalyptus plantations were taxonomically and functionally more similar to communities located in managed plantations, indicating that Eucalyptus plantations have a severe long-term impact on ant communities. These results indicate that natural regeneration may mitigate the impact of Eucalyptus management, particularly regarding the functional structure of the community (α diversity), although it does not attenuate the effects of long term homogenization in community composition (β diversity).

Small felids influence ecosystem dynamics through prey and plant population changes. Although most of these species are threatened, they are accorded one of the lowest research efforts of all felids, and we lack basic information about them. Many felids occur in sympatry, where intraguild competition is frequent. Therefore, assessing the role of interspecific interactions along with the relative importance of landscape characteristics is necessary to understand how these species co-occur in space. Here, we selected three morphologically similar and closely related species of small Neotropical cats to evaluate the roles of interspecific interactions, geomorphometry, environmental, and anthropogenic landscape characteristics on their habitat use. We collected data with camera trapping and scat sampling in a large protected Atlantic forest remnant (35,000 ha). Throughout occupancy modeling we investigated whether these species occur together more or less frequently than would be expected by chance, while dealing with imperfect detection and incorporating possible habitat preferences into the models. We used occupancy as a measure of their habitat use. Although intraguild competition can be an important determinant of carnivore assemblages, in our system, we did not find evidence that one species affects the habitat use of the other. Evidence suggested that proximity to the nature reserve (a more protected area) was a more important driver of Neotropical spotted cats' occurrence than interspecific interactions or geomorphometry and environmental landscape characteristics-even though our entire study area is under some type of protection. This suggests that small felids can be sensitive to the area protection status, emphasizing the importance of maintaining and creating reserves and other areas with elevated protection for the proper management and conservation of the group.

Forest fragmentation and habitat loss are among the major current extinction causes. Remaining fragments are mostly small, isolated and showing poor quality. Being primarily arboreal, Neotropical primates are generally sensitive to fragmentation effects. Furthermore, primates are involved in complex ecological process. Thus, landscape changes that negatively interfere with primate population dynamic affect the structure, composition, and ultimately the viability of the whole community. We evaluated if fragment size, isolation and visibility and matrix permeability are important for explaining the occurrence of three Neotropical primate species. Employing playback, we verified the presence of Callicebus nigrifrons, Callithrix aurita and Sapajus nigritus at 45 forest fragments around the municipality of Alfenas, Brazil. We classified the landscape and evaluated the metrics through predictive models of occurrence. We selected the best models through Akaike Selection Criterion. Aiming at validating our results, we applied the plausible models to another region (20 fragments at the neighboring municipality of Poço Fundo, Brazil). Twelve models were plausible, and three were validated, two for Sapajus nigritus (Area and Area+Visibility) and one for Callicebus nigrifrons (Area+Matrix). Our results reinforce the contribution of fragment size to maintain biodiversity within highly degraded habitats. At the same time, they stress the importance of including novel, biologically relevant metrics in landscape studies, such as visibility and matrix permeability, which can provide invaluable help for similar studies in the future and on conservation practices in the long run.

Movement is a key spatiotemporal process that enables interactions between animals and other elements of nature. The understanding of animal trajectories and the mechanisms that influence them at the landscape level can yield insight into ecological processes and potential solutions to specific ecological problems. Based upon optimal foraging models and empirical evidence, we hypothesized that movement by thrushes is highly tortuous (low average movement speeds and homogeneous distribution of turning angles) inside forests, moderately tortuous in urban areas, which present intermediary levels of resources, and minimally tortuous (high movement speeds and turning angles next to 0 radians) in open matrix types (e.g., crops and pasture). We used data on the trajectories of two common thrush species (Turdus rufiventris and Turdus leucomelas) collected by radio telemetry in a fragmented region in Brazil. Using a maximum likelihood model selection approach we fit four probability distribution models to average speed data, considering short-tailed, long-tailed, and scale-free distributions (to represent different regimes of movement variation), and one distribution to relative angle data. Models included land cover type and distance from forest-matrix edges as explanatory variables. Speed was greater farther away from forest edges and increased faster inside forest habitat compared to urban and open matrices. However, turning angle was not influenced by land cover. Thrushes presented a very tortuous trajectory, with many displacements followed by turns near 180 degrees. Thrush trajectories resembled habitat and edge dependent, tortuous random walks, with a well-defined movement scale inside each land cover type. Although thrushes are habitat generalists, they showed a greater preference for forest edges, and thus may be considered edge specialists. Our results reinforce the importance of studying animal movement patterns in order to understand ecological processes such as seed dispersal in fragmented areas, where the percentage of remaining habitat is dwindling.

ContextDespite the importance of secondary forests for the maintenance of biodiversity, the impact of pioneer trees on habitat loss and fragmentation is poorly understood.ObjectivesWe analyzed the effects of landscape structure on genetic variability (node level analyses) and genetic differentiation (link level analyses) of the pioneer tree Cecropia hololeuca in the Atlantic Forest of southeastern Brazil. At the node level, we analyzed the effects of landscape structure (forest and pasture amount, compositional heterogeneity, number and shape of patches, and matrix dominance), topography (slope and elevation), and effective population size (Ne) on allelic richness (AR), genetic diversity (He) and inbreeding coefficient (f). At the link level, we analyzed the effect of four resistance surfaces (isolation by geographic distance, land cover, elevation, and slope) on genetic differentiation between populations (FST, G’ST, Jost’s D).MethodsWe genotyped 257 individuals of C. hololeuca using eight microsatellite loci. At the node level, we calculated landscape and topographic variables at six spatial scales. At the link level, we optimized the resistance surfaces using ResistanceGA. We used a model selection approach to select the most parsimonious models.ResultsAt the node level, matrices dominated by pastures had higher AR than landscapes dominated by Eucalyptus at the 1500 m spatial scale. At the link level, FST was best explained by slope, with lower values imposing more resistance. All resistance surfaces explained G’ST.ConclusionsIn addition to conserving and restoring habitats, management practices that improve matrix permeability should be adopted to favor the movement of dispersers, consequently improving natural regeneration, increasing allelic richness, and decreasing genetic differentiation of natural populations.

The main effects of habitat loss and fragmentation have been addressed through changes in diversity patterns at different spatial levels. Species richness and diversity are the most used descriptors to assess the effect of changes in land use on tropical communities. However, other biological responses such as richness and diversity of trophic guilds may also provide a better understanding about the robustness and resilience of tropical environments to disturbance. In this study, we evaluated how changes in local and landscape characteristics associated to habitat loss and fragmentation affect: (i) species richness and Shannon diversity as well as (ii) trophic guild richness and diversity of leaf litter ants in human-modified tropical rainforest landscapes in Mexico. For this, we sampled ants in 16 sampling sites and recorded a series of descriptors at both local (i.e. elevation, temperature, relative humidity, soil pH, canopy cover, litter volume and vegetation structure) and landscape level (i.e. landscape heterogeneity, forest cover and connectivity). Overall, we observed that increasing primary forest cover within the sampling sites positively influenced richness and diversity of species and trophic guilds. In addition, at the local level, we found that only richness and diversity of ant species were negatively associated with tree density (i.e. number of trees, litter volume and canopy cover). These findings suggest that opportunistic species can be favored in environments with low tree density. In short, our complementary approach highlights the importance of environmental variability and primary forest cover in the maintenance of ant biodiversity in primary rainforest remnants.