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Context: Animal movement through the landscape is essential to several ecological processes, assuring genetic flow, reproductive success and population dynamics. In fragmented landscapes, species change their movement patterns according to their sensitivity to landscape cover and configuration. Increased landscape habitat loss and fragmentation affects resource distribution and habitat availability, compelling species to move more frequently through anthropized matrices. Objectives: Our aim was to provide a new prospect for what is known about animal movement through the landscape anthropogenic matrix in the Atlantic Forest biodiversity hotspot, by analyzing the potential movement distances of several mammal, bird, reptile, and amphibian species. Methods: We used recorded roadkills within the Brazilian Atlantic Forest as a source of information of species' occurrence. We assumed the euclidean distance from the roadkill spot to the nearest forest fragment as the potential movement distance by different species through the anthropogenic matrix. Experts' classification of species' forest dependence degree, and animal movement information from the literature survey was used to analyze the variation in potential animal movement distance in these matrices. Results: We analyzed 90 species, the majority of them being non-forest dependent (n = 64; 71%). The potential movement distances ranged from 0 to > 1500 m, and forest-dependent species presented lower mean distances (between 772 and 978 m) than non-forest dependent species (between 673 and 1015 m). The literature survey resulted in 44 articles regarding animal movement in the matrix, referred only to 22 species. No articles were found for 20 species, mainly reptiles and amphibians. Conclusions: By comparing these values to the average distance between forest remnants in the Atlantic Forest, we expect that the distance to be traveled through the matrix to reach forest fragments may be restrictive, mainly for species with higher degree of forest dependence. Despite being descriptive, our results provide important insights on animal movement through the matrix, especially for less studied species, such as amphibians and reptiles. [ABSTRACT FROM AUTHOR]

Understanding the response of seed rain and seed bank to landscape changes is critical for maintaining the forest remnants integrity and the potential for natural regeneration in abandoned lands. Ecological research typically focuses on direct responses of these seed processes (i.e., seed rain and seed bank), without considering the relationship between them or the indirect impact of landscape changes on these processes via its influence on seed dispersers and seed predation. Here, we employ structuring equation modeling to quantify the direct and indirect effects of landscape structure and biotic interaction on bird-dispersed seed rain and seed banks in the Atlantic Forest. We conducted the study in 20 highly fragmented landscapes. Our study shows that lower seed disperser, seed rain and seed bank abundances, as well as higher seed predation rates will be found in a landscape context with higher percentage of pasture, isolated forest fragments and in matrices far from forest edge. The indirect effect of landscape change was related to the negative influence of seed predation rates on the seed bank abundance. Based on our results, we recommend managing the landscapes trying to increase the connectivity among the forest remnants and reduce the percentage of pasture, in order to improve the seed dispersal and decrease the seed predation rates. In addition, it is essential that management plans evaluate these processes as a whole to accelerate forest recovery due to the complex relationships associated with seed rain and seed bank. Conceptual model highlighting the spatial context effects on biotic interaction (seed dispersers and predation) and seed processes (seed rain and seed bank). A At sampling local level, the seed rain and the seed predators have the opposite response to the distance to the forest edge. In addition, the seed predators vary according to the type of land cover/use. The seed predation inside the forest is lower than the outside. The highest predation was in coffee plantations. B At a landscape level, the percentage of pasture in the surrounding landscape has an inverse effect on seed predation, seed bank, and seed rain, being positive for seed predation, but negative for the seed bank and seed rain. Otherwise, the percentage of coffee plantations in the landscape has a positive effect on seed dispersers. [ABSTRACT FROM AUTHOR]

Determining the distribution and abundance of populations is the first step toward assessing biodiversity conservation status. This step is based on field observations that are largely influenced by the sampling method employed. Autonomous Recording Units (ARUs) are tools developed to improve species monitoring that employ acoustic communication. Although largely employed, the efforts required to achieve good diversity estimates with this technique are still unknown. We investigate the use of ARUs in estimating species richness of anuran assemblages in a tropical region, aiming to determine the sampling sufficiency of species richness at local and regional levels, analyze whether the asymptote point is related to forest cover, and investigate the influence of subsampling type over time on species richness estimates. We monitored amphibians in 14 streams embedded in landscapes representing a gradient from 20 to 70% native forest coverage. We detected a total of 14 species, with the regional sampling sufficiency of total species richness reached in 3448 min and influenced mainly by the terrestrial species' presence. Forest coverage had no influence on the minimum audio processing time required to achieve local asymptote. The subsampling schemes (temporally stratified and randomly assigned) had similar efficiency when using 5 min/h or more sample efforts. Our findings indicate that passive acoustic monitoring can adequately represent local anuran richness, focusing especially on the arboreal guild. Sampling effort can be optimized, with a 5 min/h duty cycle being sufficient to recover detection of most species, saving up to 75% of the effort devoted to auditing the acoustic dataset. [ABSTRACT FROM AUTHOR]

Context: Dispersal is a crucial process for species persistence under natural and disturbed landscapes. The effectiveness of stepping stones as a connectivity strategy for increasing dispersal success depends on landscape structure and animal behaviour, such as the perceptual range. Objectives: We quantify the relative contribution of stepping stones (small fragments and scattered trees) to dispersal success considering interactions with perceptual range, habitat amount and configuration. Methods: We develop an individual-based model (IBM) to simulate the dispersal movement of small mammals. The model is parametrized using empirical estimates of perceptual range and movement properties (turning angles and steps length). Simulations are implemented in landscapes with varying gradients of habitat amount and clumpiness, with and without the presence of stepping stones. Results: Small patches and scattered trees combined, or only scattered trees, have a positive effect on dispersal. Meanwhile, the presence of only small patches has negative effects on dispersal. Habitat amount positively influences dispersal, which decreases abruptly when the habitat amount is less than 20%. This threshold disappears in the presence of stepping stones. In landscapes with intermediate levels of habitat amount, landscape fragmentation (low clumpiness) has a positive effect on dispersal success. Conclusions: Stepping stones, especially scattered trees, are a fundamental connectivity strategy for the conservation of small non-flying vertebrates in human-modified landscapes, particularly landscapes with less than 20% of habitat amount. However, small patches stepping stones may act as ecological traps leading the individuals to dead-ends. Their effectiveness in improving dispersal depends on both landscape structure and perceptual range. [ABSTRACT FROM AUTHOR]

Context: An understanding of species-habitat relationships is required to assess the impacts of habitat fragmentation and degradation. To date, habitat modeling in fragmented landscapes has relied on landscape composition and configuration metrics and the importance of habitat quality in determining species distributions has not been sufficiently explored. Objectives: We evaluated how habitat use by herbivores and frugivorous mammals is shaped by a potential interaction of habitat amount and quality in the Brazilian Pantanal wetland. We also assessed if the contribution of habitat quality to species´ habitat use varies according to the species sensitivity to habitat loss. Methods: We combined mammal detection data obtained from camera traps with thematic maps to estimate the amount of habitat and measured habitat quality using local environment variables and distance to waterbodies. Specifically, we used a single-season occupancy approach to evaluate the relative support of univariate, additive, and interactive relationships between species-specific habitat use and measures of habitat quality and quantity. Results: Habitat quality was more important than habitat amount in determining species habitat use (occupancy) in a naturally fragmented landscape. Habitat quality alone was the best predictor of habitat use for two of the six species (white lipped peccary and collared peccary), but no species' habitat use was explained solely by habitat amount. Habitat amount was influential only when considered in conjunction with habitat quality covariates and only for two sensitive species to habitat loss (agouti and red brocket deer). Habitat quality alone was the best predictor of habitat use for two of the less sensitive species (white lipped peccary and collared peccary). Habitat use for two species was not explained by any covariate (tapir and gray brocket deer). Conclusions: Conservation programs should incorporate both habitat quality and amount when dealing with sensitive species and prioritize habitat quality management when focusing in less sensitive species. [ABSTRACT FROM AUTHOR]

Background: There is growing evidence that individuals within populations can vary in both habitat use and movement behavior, but it is still not clear how these two relate to each other. The aim of this study was to test if and how individual bats in a Stunira lilium population differ in their movement activity and preferences for landscape features in a correlated manner. Methods: We collected data on movements of 27 individuals using radio telemetry. We fitted a heterogeneous-space diffusion model to the movement data in order to evaluate signals of movement variation among individuals. Results: S. lilium individuals generally preferred open habitat with Solanum fruits, regularly switched between forest and open areas, and showed high site fidelity. Movement variation among individuals could be summarized in four movement syndromes: (1) average individuals, (2) forest specialists, (3) explorers which prefer Piper, and (4) open area specialists which prefer Solanum and Cecropia. Conclusions: Individual preferences for landscape features plus food resource and movement activity were correlated, resulting in different movement syndromes. Individual variation in preferences for landscape elements and food resources highlight the importance of incorporating explicitly the interaction between landscape structure and individual heterogeneity in descriptions of animal movement. [ABSTRACT FROM AUTHOR]

Plants are one of the most vulnerable groups to fragmentation and habitat loss, that may affect community richness, abundance, functional traits, and genetic diversity. Here, we address the effects of landscape features on adaptive quantitative traits and evolutionary potential, and on neutral genetic diversity in populations of the Neotropical savanna tree Caryocar brasiliense. We sampled adults and juveniles in 10 savanna remnants within five landscapes. To obtain neutral genetic variation, we genotyped all individuals from each site using nine microsatellite loci. For adaptive traits we measured seed size and mass and grown seeds in nursery in completely randomized experimental design. We obtained mean, additive genetic variance (V a ) and coefficient of variation (CV a %), which measures evolvability, for 17 traits in seedlings. We found that landscapes with higher compositional heterogeneity (SHDI) had lower evolutionary potential (CV a %) in leaf length (LL) and lower aboveground dry mass (ADM) genetic differentiation (Q ST ). We also found that landscapes with higher SHDI had higher genetic diversity (He) and allelic richness (AR) in adults, and lower genetic differentiation (F ST ). In juveniles, SHDI was also positively related to AR. These results are most likely due to longer dispersal distance of pollen in landscapes with lower density of flowering individuals. Agricultural landscapes with low quality mosaic may be more stressful for plant species, due to the lower habitat cover (%), higher cover of monocropping (%) and other land covers, and edge effects. However, in landscapes with higher SHDI with high quality mosaic, forest nearby savanna habitat and the other environments may facilitate the movement or provide additional habitat and resources for seed disperses and pollinators, increasing gene flow and genetic diversity. Finally, despite the very recent agriculture expansion in Central Brazil, we found no time lag in response to habitat loss, because both adults and juveniles were affected by landscape changes. [ABSTRACT FROM AUTHOR]

Anthropogenic activities are the main cause of habitat loss and fragmentation, which directly affects biodiversity. Disruption in landscape connectivity among populations may affect complex interactions between species and ecosystem functions, such as pollination and seed dispersal, and ultimately result in secondary extinctions. Urbanization, one of the most intense forms of landscapes changes, has been reported to negatively affect bird and plant diversity. Still, little is known about the effects of urban landscapes on interaction networks. We investigated the relationship between urban landscape structure and plant-frugivore networks at different spatial scales. Coupling interaction data from urban areas and a model selection approach, we evaluated which landscape factors best explained the variation in urban networks properties. Our results indicate that urbanization decreases bird richness, mainly through the loss of habitat specialist species, which results in networks being composed mainly of birds well adapted to urban dwelling. We found that interaction evenness, a measure of homogeneity of interaction distribution between species, increases with urbanization. This is due to the strong dominance that generalist birds had in network composition because they foraged on all available fruits, including exotic plants. The ensuing homogenization of interactions can reduce the resilience of networks and affect the efficiency of ecosystems functions. Thus, urbanization plans should consider the proportion and distribution of green areas within cities, coupling human and ecosystem wellbeing. [ABSTRACT FROM AUTHOR]

Aim: Forest fragmentation is among the principal causes of global biodiversity loss, yet how it affects mutualistic interactions between plants and animals at large spatial scale is poorly understood. In particular, tropical forest regeneration depends on animal‐mediated seed dispersal, but the seed‐dispersing animals face rapid decline due to forest fragmentation and defaunation. Here, we assess how fragmentation influences the pairwise interactions between 407 seed disperser and 1,424 tree species in a highly fragmented biodiversity hotspot. Location: Atlantic Forest, South America. Methods: We predicted interaction networks in 912 sites covering the entire biome by combining verified interaction data with co‐occurrence probabilities obtained from a spatially explicit joint species distribution model. We identified keystone seed dispersers by computing a species‐specific keystone index and by selecting those species belonging to the top 5% quantile. Results: We show that forest fragmentation affects seed dispersal interactions negatively, and the decreased area of functionally connected forest, rather than increased edge effects, is the main driver behind the loss of interactions. Both the seed disperser availability for the local tree communities and in particular the proportion of interactions provided by keystone seed dispersers decline with increasing degree of fragmentation. Importantly, just 21 keystone species provided >40% of all interactions. The numbers of interactions provided by keystone and non‐keystone species, however, were equally negatively affected by fragmentation, suggesting that seed dispersal interactions may not be rewired under strong fragmentation effects. Conclusions: We highlight the importance of understanding the fragmentation‐induced compositional shifts in seed disperser communities as they may lead to lagged and multiplicative effects on tree communities. Our results illustrate the utility of model‐based prediction of interaction networks as well as model‐based identification of keystone species as a tool for prioritizing conservation efforts. Similar modelling approaches could be applied to other threatened ecosystems and interaction types globally. [ABSTRACT FROM AUTHOR]

A decline in species number often occurs after forest fragmentation and habitat loss, which usually results in the loss of ecological functions and a reduction in functional diversity in the forest fragments. However, it is uncertain whether these lost ecological functions are consistently maintained throughout continuous forests, and so the importance of these functions in continuous forests remains unknown. Point counts were used to assess both the taxonomic and functional diversity of specialist and generalist birds from sampling in a continuous primary forest compared with forest fragments in order to investigate the responses of these groups to forest fragmentation. We also measured alpha and beta diversity. The responses of specialists and generalists were similar when we assessed all bird species but were different when only passerines were considered. When examining passerines we found lower total taxonomic beta diversity for specialists than for generalists in the continuous forest, while taxonomic beta diversity was higher in the fragmented forest and similar between bird groups. However, total functional beta‐diversity values indicated clearly higher trait regularity in continuous forest for specialists and higher trait regularity in fragments for generalists. Specialists showed significantly higher functional alpha diversity in comparison with generalists in the continuous forest, while both groups showed similar values in fragments. In passerines, species richness and alpha functional diversity of both specialist and generalist were explained by forest connectivity; but, only fragment size explained those parameters for specialist passerines. We suggest that considering subsets of the community with high similarity among species, as passerines, provides a better tool for understanding responses to forest fragmentation. Due to the regularity of specialists in continuous forest, their lost could highly affect functionality in forest fragments. [ABSTRACT FROM AUTHOR]

Context: The effects of habitat loss and fragmentation on biodiversity involve a series of mechanisms and processes that cannot be studied in isolation, mainly because human-modified landscapes are spatially heterogeneous. Despite the recent evidence on how habitat quality and landscape structure may regulate species composition and community structure, there is no empirical information on how ant-plant co-occurrence networks respond to landscape changes.Objectives: In this study, we used tools derived from landscape ecology and graph theory to model how habitat loss and forest fragmentation affect ant-plant co-occurrence networks at two different spatial levels (local and landscape) in a human-modified tropical rainforest in Mexico. Methods We sampled ant-plant co-occurrence networks in 16 landscapes and calculated species and co-occurrence diversity as well as the specialisation of the networks. For each landscape, we measured a series of biotic and abiotic variables at the local level and another set of variables at the landscape level.Results: We found that the landscape context (i.e. forest cover and landscape heterogeneity) was a better predictor of plant diversity and diversity of ant-plant co-occurrences compared with local characteristics. Moreover, we also observed that network specialisation was positively related to the amount of forest cover in landscapes.Conclusions: In short, our results highlight the importance of studying the diversity of species and co-occurrence networks within a landscape approach to predict the impact of habitat loss and fragmentation at different spatial levels and contexts. [ABSTRACT FROM AUTHOR]

Abstract: Habitat fragmentation results in landscape configuration, which affects the species that inhabit it. As a consequence, natural habitat is replaced by different anthropogenic plantation types (e.g. pasture, agriculture, forestry plantations and urban areas). Anthropogenic plantations are important for biodiversity maintenance because some species or functional groups can use it as a complementary habitat. However, depending on plantation permeability, it can act as a barrier to the movement of organisms between habitat patches, such as forest fragments, reducing functional connectivity for many species. Anthropogenic plantations are becoming the most common land use and cover type in the Anthropocene and biodiversity conservation in fragmented landscapes requires information on how different plantation types affect the capacity of the species to move through the landscape. In this study, we evaluated the influence of the type and structure of plantations on the movement of two forest‐dependent understory bird species – plain antvireo (Dysithamnus mentalis) and flavescent warbler (Myiothlyps flaveola) – within a highly fragmented landscape of Atlantic Forest hotspot. Knowing that forestry plantation is assumed to be more permeable to dependent forest bird species than open ones, we selected six study areas containing a forest fragment and surrounding plantation: three with sugarcane plantation and three with Eucalyptus sp. plantation. We used playback calls to stimulate the birds to leave forest fragments and traverse the plantations. Control trials were also carried out inside the forest fragments to compare the distances crossed. We observed that individuals moved longer distances inside forest than between plantation types, which demonstrate that plantations do constrict the movements of both species. The two plantation types equally impeded the movements of the species, suggesting the opposite of the general assumption that forestry plantations are more permeable. Our results indicate that, for generalist species, plantation type does not matter, but its presence negatively impacts movement of these bird species. We highlight that plantations have negative influences on the movements of common bird species, and discuss why this is important when setting conservation priorities. [ABSTRACT FROM AUTHOR]

Despite major advances in mammal research, there are knowledge gaps regarding distribution, composition, and the functional role of mammal species within agricultural and fragmented landscapes. Also, there is a lack of knowledge about which factors influence mammal assemblages within agricultural ecosystems. Therefore, this study aimed to estimate the contribution of forest cover, functional connectivity, drainage, and amount of sugar cane toward explaining the functional diversity of terrestrial mammals. We made an inventory of terrestrial mammals in an agricultural and fragmented landscape in an Atlantic Forest-Cerrado ecotone in southeastern Brazil, assessed the functional diversity of mammal assemblages, and proposed conservation strategies at the landscape level. Data collection occurred from September/2011 to August/2012 through a combination of complementary methods: active search; trapping stations; collection of fecal samples, which were identified by hair cuticle and fecal DNA analysis; and data from the literature. Functional diversity (FD) was calculated using a set of ecological traits including body mass, locomotion form, behavioral and dietary traits, and the environmental sensitivity of species. Akaike information criterion was used to compare generalized linear models between FD values and landscape metrics. Our results reveal a surprising insight about the role exerted by agricultural and fragmented landscapes, which still sustain impressively high biodiversity levels and a meaningful amount of ecological functions, indicating some resistance of species to pressure from the agricultural matrix and advancing urbanization. The amount of ecological functions performed by mammal species within agricultural and fragmented landscapes was similar to pristine areas and more preserved landscapes. Functional connectivity (amount of area assessed for species able to cross 200 m of matrix) was the most plausible model (wAICc = 0.873). Thus, we concluded that improving functional connectivity guarantees high FD values, and we demonstrate the importance of maintaining and restoring structural connections between fragment patches within these landscapes for species conservation and the maintenance of populations over time. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The transformation of natural landscapes in extensive anthropogenic areas has significantly affected ecological processes, and studies that evaluate such changes are essential for the definition of conservation strategies. In this study, we sought to identify the variables influencing the occupancy of Atlantic forest fragments by the endemic and endangered maned sloth. We selected 33 sampling stations, distributed at least 500 m apart throughout the municipality of Santa Maria de Jetibá—ES, Brazil. We sampled each station five times to verify the presence or absence of the species and to collect local variables. Using GIS tools, we defined a buffer of 200 m around each fragment and calculated the landscape metrics. After analysis of collinearity, we selected six variables – three local variables, two at patch level and one at landscape level – to assess their effect on the occupancy and detection probabilities. We selected models using AICc and calculated the weight of evidence and ratio of the models as well as the cumulative weight of each predictor variable. We detected the sloth in 48% of the stations. Its occupation was positively correlated to two variables on the local scale: Important Feeding Trees and Canopy height. Our results show that the maned sloth respond to fine local scale variables, but not to landscape structure. This is probably associated with the relatively high proportion of forest cover in the study area, but it also indicates the maned sloth flexibility to occupy fragmented landscape. Based on our results, we reinforce the unquestionable importance of local variables for species occupancy within fragmented landscapes, such as those related with the forest structure, and it is particularly important for strictly arboreal species. [ABSTRACT FROM AUTHOR]

Abstract: Recent global assessments have shown the limited coverage of protected areas across tropical biotas, fuelling a growing interest in the potential conservation services provided by anthropogenic landscapes. Here we examine the geographic distribution of biological diversity in the Atlantic Forest of South America, synthesize the most conspicuous forest biodiversity responses to human disturbances, propose further conservation initiatives for this biota, and offer a range of general insights into the prospects of forest species persistence in human-modified tropical forest landscapes worldwide. At the biome scale, the most extensive pre-Columbian habitats across the Atlantic Forest ranged across elevations below 800masl, which still concentrate most areas within the major centers of species endemism. Unfortunately, up to 88% of the original forest habitat has been lost, mainly across these low to intermediate elevations, whereas protected areas are clearly skewed towards high elevations above 1200masl. At the landscape scale, most remaining Atlantic Forest cover is embedded within dynamic agro-mosaics including elements such as small forest fragments, early-to-late secondary forest patches and exotic tree monocultures. In this sort of aging or long-term modified landscapes, habitat fragmentation appears to effectively drive edge-dominated portions of forest fragments towards an early-successional system, greatly limiting the long-term persistence of forest-obligate and forest-dependent species. However, the extent to which forest habitats approach early-successional systems, thereby threatening the bulk of the Atlantic Forest biodiversity, depends on both past and present landscape configuration. Many elements of human-modified landscapes (e.g. patches of early-secondary forests and tree monocultures) may offer excellent conservation opportunities, but they cannot replace the conservation value of protected areas and hitherto unprotected large patches of old-growth forests. Finally, the biodiversity conservation services provided by anthropogenic landscapes across Atlantic Forest and other tropical forest regions can be significantly augmented by coupling biodiversity corridor initiatives with biota-scale attempts to plug existing gaps in the representativeness of protected areas. [Copyright &y& Elsevier]

Ecological thresholds are an indicator of rapid and non-linear changes along both natural habitat and land-use gradients. Thus, they can be used to quantify biodiversity responses to human-induced environmental change. We investigated multiple thresholds by analyzing eight environmental predictors of both taxonomic and functional composition of amphibian and bird communities in 47 independent sample units, located within a heterogeneous land use matrix of the megadiverse Atlantic Forest hotspot. We demonstrate that current land use practices alter both the taxonomic and functional composition and promote the establishment of non-native taxa resulting in novel assemblages. Whereas anuran communities experienced dramatic compositional shifts as a result of the transformation of closed forest habitats into Eucalyptus monocultures (at less than 10% land cover), bird communities were mainly altered through the loss of old-growth forest (at 20% forest cover loss). In both groups, observed thresholds were lower than previously reported and much lower than the 20% forest set-aside requirement defined by current land-use legislation. We argue that the strategy of halting forest loss through rapid afforestation with non-native trees has converse and potentially detrimental effects on the conservation of native forest biodiversity. Future studies need to investigate how including novel assemblages in current conservation management strategies can enhance biodiversity protection in human-impacted forest landscapes. The identification of taxon-specific thresholds for both taxonomic and functional community shifts is indispensable when formulating common land use practices and designing mitigation measures. Threshold analyses can guide these actions by providing clear and quantifiable break-points for conservation practitioners. • Current land-use alters taxonomic and functional composition of frogs and birds in Atlantic Forest. • Critical environmental thresholds are lower than expected. • Afforestation with Eucalyptus monocultures facilitates invasive species. • The current land-use policy in Brazil promotes novel assemblages. • Threshold analyses can guide conservation decisions in fragmented landscapes. [ABSTRACT FROM AUTHOR]

• The maned sloth occurrence decreases abruptly below 35% of forest cover. • In areas with 20% of forest cover or lower, the occupancy probability is zero. • Open area cover have a negative influence on maned sloth occurrence. Habitat loss and the isolation of remaining habitats are undoubtedly the two greatest threats to biodiversity conservation, especially for the maned sloth, due to its ecological restrictions. In this study, we identified a critical threshold of forest cover for maned sloth occurrence and explored the effects of other local and landscape variables. We sampled 68 sites, where we searched for the maned sloth and collected local habitat variables. We calculated the percentage of forest cover and open areas, assessing the appropriated scale through model selection. We used occupancy models and model selection methods to identify the threshold and assess occupancy and detection probabilities. The occupancy probability of the maned sloth is 0.97, but it decreases abruptly at 35% of forest cover, reaching zero in areas with less than 20% of forest cover. The two landscape variables are the most important predictors of sloth occupancy, based on the cumulative weight of evidence, were: Forest cover (78%) and Open areas cover (46%); the latter influencing negatively maned sloth occupancy. This is the first attempt to identify the habitat requirements of the threatened maned sloth in a fragmented area using landscape and local variables. Our results imply that conservation of maned sloth will benefit from an increase in the amount of native forest at the landscape scale. Given difficulties in the creation of new public protected areas, this improvement could be achieved via the recovery of areas located in private properties that are protected by the Brazilian Forest Code. [ABSTRACT FROM AUTHOR]

Habitat fragmentation threatens tropical rainforests, which can significantly hinder dispersal in species such as arboreal primates. For conservation actions to be effective there must be an understanding of how landscape structure and biological traits shape dispersal. We assessed the effects of landscape, sex and population management (reintroductions and translocations) on gene flow of Leontopithecus rosalia , an endangered arboreal primate living in highly fragmented forests of Brazil. We genotyped 201 individuals using 14 microsatellite loci to answer three questions: (1) How far does L. rosalia disperse? (2) Is dispersal sex-biased? (3) What are the relative contributions of population management, distance, roads and landscape resistance to genetic kinship? We hypothesized that (1) gene flow decrease between more distant sites; (2) males disperse more than females; and (3) management and land-cover resistance ( i.e. landscape resistance) are the variables that most influence genetic kinship. We found positive spatial population-structure up to 8 km. The spatial structure was similar between females and males suggesting that they equally contribute to gene flow. Management and landscape resistance best explained genetic kinship, showing that different land-cover types affect the dispersal at different degrees of landscape permeability. We advocate that maintaining more permeable landscapes is essential to ensure dispersal and gene flow of arboreal mammals. Conservation measures in tropical rainforests must take into account not only the habitat amount, but also the degree at which each land use – roads, urban areas, agriculture, pasture, isolated trees, and stepping stones – facilitates or impedes the species dispersal. [ABSTRACT FROM AUTHOR]

Time-lagged responses of biological variables to landscape modifications are widely recognized, but rarely considered in ecological studies. In order to test for the existence of time-lags in the response of trees, small mammals, birds and frogs to changes in fragment area and connectivity, we studied a fragmented and highly dynamic landscape in the Atlantic forest region. We also investigated the biological correlates associated with differential responses among taxonomic groups. Species richness and abundance for four taxonomic groups were measured in 21 secondary forest fragments during the same period (2000–2002), following a standardized protocol. Data analyses were based on power regressions and model selection procedures. The model inputs included present (2000) and past (1962, 1981) fragment areas and connectivity, as well as observed changes in these parameters. Although past landscape structure was particularly relevant for trees, all taxonomic groups (except small mammals) were affected by landscape dynamics, exhibiting a time-lagged response. Furthermore, fragment area was more important for species groups with lower dispersal capacity, while species with higher dispersal ability had stronger responses to connectivity measures. Although these secondary forest fragments still maintain a large fraction of their original biodiversity, the delay in biological response combined with high rates of deforestation and fast forest regeneration imply in a reduction in the average age of the forest. This also indicates that future species losses are likely, especially those that are more strictly-forest dwellers. Conservation actions should be implemented to reduce species extinction, to maintain old-growth forests and to favour the regeneration process. Our results demonstrate that landscape history can strongly affect the present distribution pattern of species in fragmented landscapes, and should be considered in conservation planning. [Copyright &y& Elsevier]