The fragmentation of the Brazilian Atlantic Forest has led to partially isolated fragments under strong edge effects. At the edges of these fragments, there is usually dominance of native climbing species and invasive African grasses. The high density of climbers creates a “wall” around the forest, known to hamper seedling establishment and eventually limit forest regeneration. We hypothesize that, to some extent, this dense “wall” formed by native climbing species may act as a barrier against the spread of invasive grasses into forest fragments. In this study, we investigated how the abundance of native climbers affects the abundance of invasive grasses at forest edges, and whether climbers influence seedling establishment and woody species richness. We conducted vegetation surveys at 45 edges distributed among private and public protected areas, via plot sampling (1 m2; n = 1,225). We used Generalized Linear Mixed Models to investigate: (i) the effects of climber abundance (predictor) on the abundance of invasive grasses (response); (ii) the effects of climber and invasive grass abundance (predictors) on the abundance of eudicot seedlings (response); and (iii) the effects of average climber and invasive grass abundance (predictors) on species richness of trees and shrubs (response). The abundance of native climbers negatively affected the abundance of invasive grasses and reduced the establishment of eudicot seedlings. However, it did not affect species richness of native trees and shrubs. The effect of climbers on invasive grasses directly reduces the risk of wildfires, especially during the dry season. We understand that, despite these evidences, restoration projects may still have reasons to manage climbers in areas under regeneration. Then, we propose five main aspects to be carefully considered before initiating any direct intervention on climbers, considering the risk of fire and distribution of local species.
Protected areas (PAs) are one of the central tools to achieve international conservation targets toward 2030, yet biases in their location often undermine their effectiveness. A recurrent pattern worldwide is the tendency to establish PAs in remote or marginal lands, the so-called “residual conservation” or “rock and ice problem”. While elevation has been widely studied as a driver of this bias, other key topographic dimensions have received far less attention. Here we compared altitude, slope, and irregularity within Argentinian PAs against national, local, and ecoregional baselines, and examined their variation with the year of establishment and IUCN category. Our results show that Argentine PAs are disproportionately located in higher, steeper, and more irregular environments, with these biases being most pronounced in strictly protected categories. Protection increases sharply above 2000 m, in slopes steeper than 27 °, and in rugged terrains, while fertile and accessible lowlands remain largely underrepresented. These biases show little evidence of having changed substantially through time, despite Argentina’s international commitments on biological representativeness. Overcoming these long-standing topographic biases to truly meet the international agenda will require moving beyond economically convenient expansions and strategically directing protection toward the current deficits of the system, even when this implies political conflict.
Landscape transformation alters species diversity and the functional structure of communities. In the Serranía del Perijá, northern Colombia, we assessed how landscape composition and configuration influence taxonomic and functional diversity (alpha and beta) of phytophagous scarab beetles (Scarabaeidae) across forests, crops, and regenerating areas within four landscape windows. A total of 3,713 individuals representing 50 species were collected using baited and light traps. Regionally, taxonomic alpha diversity metrics (°D, 1D, 2D), functional richness (FRicSES), and functional dispersion (FDisSES) did not differ significantly among land-cover types, although local contrasts were evident. Functional evenness (FEveSES) was lower in regeneration, and several species were unique to forests and regeneration but absent from crops. Generalized additive mixed models identified significant relationships between landscape variables and taxonomic richness, whereas patch shape, canopy-cover dissimilarity, and PLAND were associated with beta-diversity patterns among land-cover types. Taxonomic beta diversity was mainly driven by species turnover, whereas functional beta diversity was dominated by nestedness, suggesting reduced functional differentiation among communities. These findings highlight the importance of landscape configuration and connectivity in maintaining diversity in transformed tropical systems.
Several studies have highlighted the impacts of roads and highways on species dispersal, abundance, and persistence, since these are the infrastructures that most threaten biodiversity. Yet, little is known about how roads affect community assembly processes at broader spatial extents. Understanding interactions between roads and community assembly processes is an urgent need especially in tropical areas, where key biodiversity hotspots and ecosystem services are critically threatened. Here, we review how roads could shape community assembly processes and (meta)community structure across biogeographic extents for animals, with a focus on identifying causal effects. We use causal diagrams to illustrate the expected relationships among variables representing processes influencing species composition and dissimilarity under road influence. In doing so, we highlight how observational studies on road effects are prone to confounding and bias, using the concrete example of the controversial BR-319 highway in the Amazon. We propose the use of quasi-experimental designs as an alternative for better assessing the impacts of roads’ construction on animal communities. We conclude that more integrated and multi-process approaches are needed to study (meta)communities, moving from mere descriptions of correlations to the identification of the causality of ecological processes. This can be more easily achieved by integrating spatial and temporal ecological data.
Carrion is a nutrient-rich yet unpredictable resource sustaining diverse vertebrate scavengers. We examined how environmental filters and species associations relate to scavenger guild structure under land-use change. In the Chilean Patagonian steppe, we deployed 70 ram carcasses across gradients of livestock management pressure, using a camera traps. At each carcass, we quantified species richness and a relative abundance index and applied Hill numbers (q = 0, 1, 2) to assess diversity, relating patterns to environmental variables and to large carnivores (puma Puma concolor and culpeo fox Lycalopex culpaeus) and dominant scavengers (Andean condor Vultur gryphus, grey fox L. griseus, kelp gull Larus dominicanus). We recorded 41 vertebrate species using carrion (i.e., interacting directly with carcass tissue or fluids), representing the highest richness reported for steppe ecosystems. Guild composition varied spatially, with facultative scavengers (kelp gulls, grey foxes) numerically replacing condors at some sites. Presence of puma and culpeo fox was associated with more even and diverse assemblages, whereas Andean condor and grey fox were associated with increased unevenness. These patterns suggest that species identity and livestock management are important correlates of scavenger community structure. Our findings provide a regional baseline for understanding how livestock management and large carnivore occurrence relate to carrion-mediated ecosystem processes.
Fire has been a fundamental tool for human evolution and well-being. In slash-and-burn agriculture (SBA), it has been used for millennia to eliminate field debris, accelerate the incorporation of nutrients into the soil, and control weeds. However, in addition to these desired outcomes, fire can have multiple undesired environmental impacts that threaten the sustainability of tropical forests and SBA itself. We hypothesized that the environmental costs of fire use in SBA can outweigh its agronomic benefits across tropical forests. To assess this hypothesis, we critically reviewed empirical evidence on both desired and undesired environmental effects of SBA-related fire across the tropics worldwide. We found that fire effectively facilitates land clearing and releases nutrient-rich ashes that temporarily fertilize the soil. However, this fertilization is short-lived and restricted to the topsoil, while a substantial fraction of forest nutrients is wasted through volatilization and post-fire erosion. SBA-related carbon emissions may also contribute to climate forcing at regional and global scales. Although fire can reduce weed pressure by damaging seeds and limiting seed bank viability, this recruitment limitation can delay or arrest secondary succession, thereby constraining forest recovery and its ability to offset fire damage in SBA-dominated landscapes. In addition, repeated burning increases the risk of accidental wildfires, amplifying forest loss and associated biodiversity loss and carbon emissions. Elevated soil temperatures during burning can negatively impact soil biota, disrupting their essential ecological functions. Overall, despite notable remaining knowledge gaps, our review suggests that the environmental costs of using fire in SBA outweigh its benefits.
Domestic dogs (Canis lupus familiaris) are the most widespread carnivores and act as disruptive agents in insular ecosystems. In Tierra del Fuego, feral dogs have expanded into rural landscapes, affecting wildlife and livestock. Using 21 camera traps, we assessed their presence, activity, and interactions with the Fuegian culpeo fox (Lycalopex culpaeus lycoides), the chilla fox (Lycalopex gymnocercus), and guanacos (Lama guanicoe). We identified 117 individuals, roaming solitary or in groups of up to nine. Reproductive activity was evident, with 87 pup detections, especially during autumn and winter. Dogs exhibited stable bimodal diel patterns, peaking in the morning and late afternoon, and shifting toward nocturnality in winter. Overlap was moderate-to-high with guanacos (Δ = 0.73, peaking in winter at Δ = 0.82) and moderate with chilla foxes (Δ = 0.65). The endangered culpeo was never recorded, raising conservation concerns. Chase events and injured guanacos evidenced direct predatory impacts. Over five years, dog detections increased almost 230%, while chilla detections declined by 66%, suggesting competitive displacement. Forest patches were frequently used by dogs, potentially as shelter and breeding sites. These findings suggest that feral dogs function as apex predators in this system, highlighting the urgent need for management to mitigate their ecological and economic impacts.
Land-use intensification reshapes tropical landscapes, altering the spatial structure of habitats and affecting acoustically active biodiversity. We assessed how habitat amount and landscape heterogeneity jointly influence soundscapes in 72 Atlantic Forest landscapes spanning 5–85% native vegetation. We calculated acoustic diversity (ADI, Distribution of acoustic energy across frequency bands) and acoustic complexity (ACI, Variability in acoustic amplitude) based on autonomous audio recordings for diurnal, nocturnal, and combined periods. ADI decreased with increasing habitat amount, likely reflecting the dominance of generalist and insect-driven acoustic signatures in more altered landscapes. In contrast, ACI increased with habitat amount, but this effect depended strongly on landscape heterogeneity. Heterogeneous landscapes maintained high ACI even at <40% habitat cover, acting as a buffer against soundscape degradation, whereas homogeneous landscapes required more than 40–50% habitat to reach comparable levels of acoustic complexity. These findings show that, under ongoing intensification and simplification of human-modified landscapes, maintaining the same proportion of native vegetation may still lead to biodiversity loss if heterogeneity declines. Integrating habitat amount and heterogeneity into conservation planning is therefore essential for sustaining the structure and function of acoustic communities in human-modified tropical regions.
Overexploitation of forest systems by human actions can lead to the local and selective extinction of animal species, a phenomenon known as defaunation. Several studies showed increased abundance of small mammals under high-defaunation of medium- and large-bodied animals. The absence of seed dispersers can preclude the regeneration of several plant species. Araucaria angustifolia is classified as a keystone and a critically endangered species, so understanding the factors limiting its regeneration is essential. The main objective of this study was to quantify the effects of small mammal richness and mammal defaunation under the regeneration of araucaria across a regional scale in southern Brazil. We expected that sites with greater defaunation and larger assemblages of small mammals would demonstrate less regeneration – since this could lead to reduced seed dispersal and increased seed predation. Our best-fitting model considered adult density, defaunation, richness of small-bodied mammals, canopy openness, and the presence/absence of cattle as predictors of araucaria regenerant density. We found a negative relationship between mammal defaunation and araucaria regeneration. Our results also revealed that the top-10 richest sites in terms of small mammals had a defaunation rate of 0.60 (18% larger than the mean defaunation) and embraced only 100 araucaria regenerants (1.7% of total). Therefore, the mammal defaunation is an important threat to Araucaria Mixed Forest (AMF) functioning and conservation.
Global efforts to halt biodiversity loss and address climate change increasingly depend on scientific knowledge generated in the Amazon. The outcomes of COP30, hosted in Belém in November 2025, reaffirmed the centrality of Amazonian science to global environmental agendas, while also exposing persistent structural constraints that limit its effectiveness. Fragmented governance, short-term and externally controlled funding, and enduring inequities in leadership, data ownership, and decision-making continue to undermine the region’s capacity to deliver credible, policy-relevant, and socially legitimate science at scale. Here, we argue that incremental reforms are insufficient. We identify three interrelated bottlenecks: integration across initiatives, co-governance with local institutions and knowledge holders, and long-term funding stability, and propose a collaborative, polycentric framework to address them. We further argue that, without structural transformation, current investments risk reproducing existing asymmetries rather than enabling durable and territorially grounded conservation outcomes. We outline priority actions for governments, funders, and research networks to consolidate Amazon-based leadership and translate scientific investments into durable conservation and socio-ecological outcomes beyond COP30.
Climate change is significantly altering species distributions worldwide, expanding the range of some and reducing suitable habitats for others. Concerning snakes, these changes have direct public health implications, as venomous snake species may invade new areas, including densely populated urban zones. This increases the need for appropriate antivenom distribution strategies, particularly in remote areas or those displaying limited healthcare infrastructure. While several studies have focused on climate change snake habitat effects, few have addressed how this affects snakebite treatment center logistics and organization. In this context, we aimed to assess if snake distribution changes driven by climate change require the restructuring of antivenom treatment center networks (ATCN) in Brazil. To this end, we applied occurrence records from herpetological collections alongside bioclimatic and land use variables to species distribution models employing five different algorithms considering projected 2061–2080 climate change scenarios under mitigated (SSP 2−4.5) and unchecked (SSP 5–8.5) conditions. The developed models indicate suitable snake area decreases, as well as species richness, particularly under the SSP 5–8.5 scenario. We identified a spatial mismatch, with suitable snake areas displaying up to 63% ATCN coverage deficit, particularly in extremely remote regions, especially for the Bothrops and Micrurus genera. In contrast, ATCNs carrying antivenom, particularly for the Lachesis and Crotalus genera, were noted in up to 92% of unsuitable snake areas. These findings highlight the need for constant ATCN location reassessments considering future climate change scenarios to ensure more effective snakebite incident responses, also emphasizing the importance of adopting an integrated health approach considering human, animal, and environmental health interactions to improve snakebite risk management in Brazil.
Brazil’s recent environmental licensing reform exposes a contradiction between national regulation and international climate and biodiversity commitments. Law No. 15.190/2025 narrows analytical scope, expands exemptions, weakens preventive mechanisms, and shifts responsibilities to subnational authorities with uneven technical capacity. Although environmental impact assessments remain formally required, the law reduces their applicability and overlooks indirect, cumulative, and synergistic impacts. It also omits ecosystem services, despite scientific consensus on their role in climate regulation, water provision, soil protection, and pollination. This omission underestimates socio-environmental risks and undermines resilience, food security, and long-term planning. This contradiction is evident in Brazil’s renewed international engagement, including its role as host of the 30th United Nations Climate Change Conference (COP30) in Belém. To align national regulation with global commitments, integrating ecosystem services into licensing, alongside transparency and impact data disclosure, is urgently needed.
Despite their ecological importance, carnivorans are often underrepresented in protected areas (PAs), making it crucial to evaluate the representation of their richness and endemicity patterns within these areas for effective conservation. The Yucatan Peninsula (YP), a unique biogeographic province, harbors 18 carnivoran species (∼22% of the Americas’ carnivoran diversity). Using ecological niche modeling and diversity range analysis, we assessed the spatial representation of these patterns within the region’s PAs. Our results show that peak species richness occurs in southern Quintana Roo, southeastern Campeche, the Tabasco-Chiapas border (Mexico), and northern Belize-Guatemala, while endemicity is highest on Cozumel Island and in south-central Tabasco. However, only 9.48 % of high-richness and high-endemicity areas lie within existing PAs. Key PAs partially covering these priority zones include Sierra del Lacandón, Laguna del Tigre, Tikal, and Yaxhá-Nakum-Naranjo National Parks (Guatemala); the Rio Bravo Conservation Area (Belize); and the Calakmul Biosphere Reserve (Mexico). These findings underscore the need to expand PA coverage and enhance systematic assessments of biodiversity patterns within them to safeguard the YP’s unique carnivoran assemblages and their ecosystem functions.
Sylvilagus insonus is an endemic rabbit of the Sierra Madre del Sur, Guerrero, Mexico, considered one of the most endangered and least studied lagomorphs worldwide. After more than 20 years without records, it was rediscovered through citizen science observation, renewing interest in its ecology and conservation. This study assessed its relative abundance across vegetation types and localities, potential predators, activity patterns, and threats. We deployed camera traps to estimate the Relative Abundance Index (RAI) of S. insonus and its potential predators. Linear regressions were used to analyze the relationship between rabbit abundance, habitat type, and predator presence. Activity patterns were determined for S. insonus and recorded carnivores. Additional threats were documented during fieldwork. A total of 127 independent records of S. insonus were obtained, with an average RAIij of 16.11 ± 14.69. Five potential predators were identified: Urocyon cinereoargenteus, Puma concolor, Leopardus pardalis, Leopardus wiedii, and Herpailurus yagouaroundi. No significant differences were detected between the RAIij of the rabbit and those of its predators. Activity data indicated that S. insonus is both diurnal and nocturnal. No significant difference was found between habitat types, although it was mostly detected in mixed forests. Main threats observed included logging, forest fires, and hunting. These findings provide the first ecological insights into S. insonus and highlight urgent conservation needs. To ensure the species’ persistence, it is crucial to promote sustainable forest management, strengthen fire prevention, increase community involvement, and maintain long-term monitoring with support from authorities and international organizations.
As a vital component of global food security and ecosystem health, pollinators are essential for sustaining both natural systems and human populations, yet their numbers continue to decline despite extensive conservation efforts. Although well-known threats such as habitat loss, pesticides, and climate change remain serious concerns, focusing only on well-known threats could overshadow the necessity of re-orienting conservation agendas to address new pressures and opportunities created by rapidly shifting environmental, technological, and socio-political landscapes, which have yet to be fully integrated into conservation agendas. We synthesise the findings of a global rapid assessment that used expert elicitation to identify urgent emerging global threats and opportunities for pollinators. Emerging threats stemmed from diverse sources, including novel forms of pollution (such as microplastics, artificial light, heavy metals, and nitrogen oxides) and the compounding effects of well-known stressors. Conversely, significant opportunities for pollinator conservation were found in the strategic use of novel tools and technology for targeted conservation, and in solutions that benefit multiple ecosystem services through novel land uses. Further research into these key areas will allow us to act early on these findings to better protect pollinators in the future and preserve the benefits they provide for people and nature.
Agricultural intensification is one of the leading drivers of global biodiversity loss. Assessing its ecological impacts requires more than just measuring species richness; incorporating functional diversity allows for deeper insight into changes in community structure and ecosystem functioning. Amphibians are sensitive to environmental change, making them ideal indicators of ecosystem health. In this study, we examined how agricultural management influences the taxonomic and functional diversity of anuran communities in the Brazilian Pampa. We surveyed anurans in 26 ponds across 16 family farms (nine organics and seven conventional), sampled three times during the 2023–2024 breeding seasons. Diversity metrics were assessed at both the pond and farming levels, incorporating local habitat features and landscape composition at multiple spatial scales. Results showed that organic agroecosystems supported higher species richness at the pond scale, although functional diversity did not differ between management types at this level. In contrast, at the agroecosystem scale, organic farming supported higher functional diversity than conventional systems. Additionally, we found a significant interaction between management type and surrounding forest cover: organic farming adjacent to forest patches had the highest diversity values. Our findings highlight the importance of integrating sustainable agricultural practices with the conservation of natural landscape elements. Promoting organic farming alongside the preservation of native habitats can help mitigate the negative effects of intensification and enhance biodiversity in agricultural landscapes.
The rapid expansion of irrigation infrastructure in the Brazilian Cerrado is creating new challenges for biodiversity conservation. In this study, we report the first documented cases of maned wolves (Chrysocyon brachyurus) killed by open irrigation canals in Brazil, a previously unrecognized threat to the species' survival in agricultural landscapes. Beyond its impact on maned wolves, these findings suggest that such structures pose a widespread but overlooked danger to native Cerrado fauna. Currently, environmental licensing for irrigation projects lacks legal requirements to mitigate wildlife impacts, representing a critical policy gap. To address this issue, coordinated efforts integrating scientific research, governance reforms, and market driven solutions are urgently needed to prevent further biodiversity loss in these rapidly changing ecosystems.
Whether a Single Large (SL) is better than Several Small (SS) areas of natural vegetation (SLOSS) to maintain biodiversity in human-altered landscapes is still contentious. Here, we argue that the SLOSS debate has no single solution, because SS may have higher species richness (γ-diversity) than a SL and that it is critical for biodiversity conservation. We used multitaxa data from different years sampled in an experimental area designed to test SLOSS predictions and dominated by intensive farming. We compared whether a SL patch of natural vegetation has higher species richness than the sum of SS patches with total area equal to the SL. We found that for most taxa SS had higher γ-gamma diversity than a SL. Furthermore, beta diversity among SS was not correlated with spatial distance among them for most taxa. Our findings underscore that the contribution of SL or SS to maintain species richness cannot be generalized. Therefore, the importance of SS for maintaining biodiversity in agricultural landscapes, which intrinsically can support different mechanisms and interactions compared to landscapes with lower anthropic influence, need to be properly recognized, keeping the SS in a leading role as they are most of the natural vegetation areas remaining worldwide.
Electrocution on power lines is a major bird mortality source and an important global conservation issue. However, avian electrocution studies are scarce in large regions such as the Neotropical area. Here we evaluate electrocutions recorded across eight provinces of Argentina from 2019 to 2025 and address the characteristics of the poles involved in these events. 160 birds of 18 species were found electrocuted, of which 150 individuals belong to 12 raptor species. The species most affected by this human-induced cause of mortality were the Black-chested Buzzard-eagle (Geranoaetus melanoleucus) -most of which were immatures-, the Variable Hawk (G. polyosoma), the Black Vulture (Coragyps atratus), and the endangered Chaco Eagle (Buteogallus coronatus). We also document for the first time the electrocution of six new bird species. Most electrocutions occurred in winter, and at poles of steel-reinforced concrete, of three-phase power lines with pin insulators and the wires over concrete crossarms. Other recurring characteristics in deadly poles included jumper wires over the crossarms and/or lightning rods in both single- and three-phase power lines. Except a case of electrocution at a pole retrofitted with a useless supplementary perch, none of them had any electrocution mitigation measures (e.g., insulators) implemented. Given the severity of this source of mortality and the increasing knowledge of the pole characteristics that provoke bird electrocution, we propose a large-scale collaborative dataset of avian electrocution, and we urge authorities, lawmakers, and energy companies to implement effective mitigation measures at risky poles and to develop bird-friendly designs for future power lines.
The encroachment of woody vegetation into grasslands is a trend in grass-dominated ecosystems worldwide. In the long term, woody vegetation can completely replace grassland vegetation, displacing grassland-dependent bird species. We aimed to evaluate the effects of woody vegetation removal on grassland birds in a legally protected grassland area by monitoring the bird community over eight sampling periods, before and after woody vegetation removal. Grassland bird richness and abundance increased significantly immediately after woody vegetation removal, then decreased two years after removal. The opposite trend occurred with forest bird richness and abundance, decreasing immediately after woody vegetation removal and increasing significantly two years after removal. The results indicate that the removal of woody vegetation improves the quality and quantity of habitat for grassland-dependent bird species and that it can be used as an important conservation strategy in protected areas of the grasslands of southern South America.
