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1.
Conserv Biol ; : e14245, 2024 Mar 08.
Article En | MEDLINE | ID: mdl-38456548

Understanding which species will be extirpated in the aftermath of large-scale human disturbance is critical to mitigating biodiversity loss, particularly in hyperdiverse tropical biomes. Deforestation is the strongest driver of contemporary local extinctions in tropical forests but may occur at different tempos. The 2 most extensive tropical forest biomes in South America-the Atlantic Forest and the Amazon-have experienced historically divergent pathways of habitat loss and biodiversity decay, providing a unique case study to investigate rates of local species persistence on a single continent. We quantified medium- to large-bodied mammal species persistence across these biomes to elucidate how landscape configuration affects their persistence and associated ecological functions. We collected occurrence data for 617 assemblages of medium- to large-bodied mammal species (>1 kg) in the Atlantic Forest and the Amazon. Analyzing natural habitat cover based on satellite data (1985-2022), we employed descriptive statistics and generalized linear models (GLMs) to investigate ecospecies occurrence patterns in relation to habitat cover across the landscapes. The subregional erosion of Amazonian mammal assemblage diversity since the 1970s mirrors that observed since the colonial conquest of the Atlantic Forest, given that 52.8% of all Amazonian mammals are now on a similar trajectory. Four out of 5 large mammals in the Atlantic Forest were prone to extirpation, whereas 53% of Amazonian mammals were vulnerable to extirpation. Greater natural habitat cover increased the persistence likelihood of ecospecies in both biomes. These trends reflected a median local species loss 63.9% higher in the Atlantic Forest than in the Amazon, which appears to be moving toward a turning point of forest habitat loss and degradation. The contrasting trajectories of species persistence in the Amazon and Atlantic Forest domains underscore the importance of considering historical habitat loss pathways and regional biodiversity erosion in conservation strategies. By focusing on landscape configuration and identifying essential ecological functions associated with large vertebrate species, conservation planning and management practices can be better informed.


Uso de la pérdida histórica de hábitat para predecir la desaparición de mamíferos contemporáneos en los bosques neotropicales Resumen Tener conocimiento de cuáles especies desaparecerán después de una perturbación humana es de suma importancia para mitigar la pérdida de la biodiversidad, particularmente en los biomas híper diversos. La deforestación es la principal causante de las extinciones locales contemporáneas en los bosques tropicales, aunque puede ocurrir en diferentes tiempos. Los dos bosques tropicales más extensos de América del Sur - el Bosque Atlántico y la Amazonia - han experimentado formas históricamente divergentes de pérdida de hábitat y decadencia de biodiversidad, lo que proporciona un caso único de estudio para investigar las tasas de persistencia de las especies locales en un solo continente. Cuantificamos la persistencia de las especies de mamíferos de talla mediana a grande en estos dos bosques para aclarar cómo la configuración del paisaje afecta su persistencia y las funciones ecológicas asociadas. Recolectamos datos de presencia de 617 ensambles de especies de mamíferos de talla mediana a grande (>1 kg) en el Bosque Atlántico y en la Amazonia. Analizamos la cobertura natural del hábitat con base en datos satelitales (1985-2022) y empleamos estadística descriptiva y modelos lineales generalizados (MLG) para investigar los patrones de presencia de las eco especies en relación con la cobertura del hábitat en los distintos paisajes. La erosión subregional de la diversidad de ensambles de mamíferos en la Amazonia desde los 70s es igual a la observada en el Bosque Atlántico desde la conquista colonial, dado que 52.8% de todos los mamíferos amazónicos se encuentran en una trayectoria similar. Cuatro de los cinco grandes mamíferos en el Bosque Atlántico estaban propensos a desaparecer, mientras que el 53% de los mamíferos amazónicos estaban vulnerables a desaparecer. Una mayor cobertura natural del hábitat incrementó la probabilidad de persistencia de las eco especies en ambos bosques. Estas tendencias reflejaron una pérdida mediana de especies locales 63.9% mayor en el Bosque Atlántico que en la Amazonia, lo cual parece dirigirse hacia un momento decisivo para la degradación y pérdida del hábitat del bosque. Las trayectorias contrastantes de la persistencia de especies en el Bosque Atlántico y la Amazonia destacan la importancia de considerar dentro de las estrategias de conservación las maneras en las que se ha perdido históricamente el hábitat y la erosión de la biodiversidad regional. Si nos enfocamos en la configuración del paisaje y en la identificación de las funciones ecológicas esenciales asociadas con las especies grandes de vertebrados, podemos informar de mejor manera a la planeación de la conservación y las prácticas de manejo.

2.
An Acad Bras Cienc ; 95(suppl 2): e20220746, 2023.
Article En | MEDLINE | ID: mdl-38126433

Coats-of-arms representing municipal counties express local patterns of rural economics, natural resource and land use, features of the natural capital, and the cultural heritage of either aborigines or colonists. We reconstruct the subnational economic and political timeline of the world's largest tropical country using municipal coats-of-arms to reinterpret Brazil's historical ecology. We assessed all natural resource, biophysical, agricultural, and ethnocultural elements of 5,197 coats-of-arms (93.3%) distributed throughout Brazil. We extracted socioenvironmental co-variables for any municipality to understand and predict the relationships between social inequality, environmental degradation, and the historical ecology symbology. We analyzed data via ecological networks and structural equation models. Our results show that the portfolio of political-administrative symbology in coats-of-arms is an underutilized tool to understand the history of colonization frontiers. Although Brazil is arguably Earth's most species-rich country, generations of political leaders have historically failed to celebrate this biodiversity, instead prioritizing a symbology depicted by icons of frontier conquest and key natural resources. Brazilian historical ecology reflects the relentless depletion of the natural resource capital while ignoring profound social inequalities. Degradation of natural ecosystems is widespread in Brazilian economy, reflecting a legacy of boom-and-bust rural development that so far has failed to deliver sustainable socioeconomic prosperity.


Conservation of Natural Resources , Ecosystem , Humans , Conservation of Natural Resources/methods , Socioeconomic Factors , Brazil , Rural Population , Agriculture
3.
Sci Data ; 10(1): 771, 2023 11 06.
Article En | MEDLINE | ID: mdl-37932332

Global change is predicted to induce shifts in anuran acoustic behavior, which can be studied through passive acoustic monitoring (PAM). Understanding changes in calling behavior requires automatic identification of anuran species, which is challenging due to the particular characteristics of neotropical soundscapes. In this paper, we introduce a large-scale multi-species dataset of anuran amphibians calls recorded by PAM, that comprises 27 hours of expert annotations for 42 different species from two Brazilian biomes. We provide open access to the dataset, including the raw recordings, experimental setup code, and a benchmark with a baseline model of the fine-grained categorization problem. Additionally, we highlight the challenges of the dataset to encourage machine learning researchers to solve the problem of anuran call identification towards conservation policy. All our experiments and resources have been made available at https://soundclim.github.io/anuraweb/ .


Anura , Vocalization, Animal , Animals , Acoustics , Ecosystem
4.
J Anim Ecol ; 90(12): 2729-2743, 2021 12.
Article En | MEDLINE | ID: mdl-34553786

New World bats are heavily affected by the biophysical setting shaped by elevation and latitude. This study seeks to understand the patterns of bat species diversity across elevational, latitudinal and vegetation height gradients throughout the Neotropics. Systematically gathered putative and empirical data on bat species distribution across the entire Neotropics were examined using descriptive statistics, spatial interpolation of bat taxonomic, functional and phylogenetic diversity, generalized linear models, generalized linear mixed models and phylogenetic generalized least squares. We uncoupled the effects of elevation, latitude and vegetation height to predict Neotropical bat diversity, showing that dietary level, home range and habitat breadth were the most important ecological traits determining coarse-scale bat distributions. Latitude was largely responsible for sorting the regional species pool, whereas elevation appears to apply an additional local filter to this regional pool wherever tropical mountains are present, thereby shaping the structure of montane assemblages. Bats provide multiple ecosystem services and our results can help pinpoint priority areas for bat research and conservation across all Neotropics, elucidate the thresholds of species distributions, and highlight bat diversity hotspots at multiple scales.


Assembleias de morcegos neotropicais são fortemente moldadas pelo ambiente biofísico que, por sua vez, é determinado pela elevação e latitude. Buscamos compreender neste estudo os padrões de diversidade de espécies de morcegos em gradientes de altitude, latitude e altura da vegetação ao longo de todo o domínio neotropical. Examinamos dados teóricos e empíricos sobre a distribuição de espécies de morcegos neotropicais, coletados sistematicamente, usando estatística descritiva, interpolação espacial de diversidade taxonômica, funcional e filogenética, modelos lineares generalizados, modelos lineares generalizados mistos e modelos generalizados filogenéticos. Desacoplamos os efeitos da altitude, latitude e altura da vegetação para predizer a diversidade de morcegos neotropicais, mostrando que nível trófico, tamanho da área de vida e especificidade de uso de habitats foram os traços ecológicos mais importantes que determinam as distribuições de morcegos em grande escala. A latitude foi amplamente responsável por determinar o conjunto regional de espécies, enquanto que a elevação parece aplicar um filtro local adicional no conjunto quando na presença de montanhas tropicais, moldando assim a estrutura das assembleias montanas de morcegos. Os morcegos atuam em vários serviços ecossistêmicos e nossos resultados podem ajudar a identificar áreas prioritárias para pesquisa e conservação de morcegos em toda a região neotropical, elucidar os limites de distribuição de espécies e destacar pontos críticos de diversidade de morcegos em múltiplas escalas.


Chiroptera , Animals , Biodiversity , Diet , Ecosystem , Phylogeny
5.
Glob Chang Biol ; 27(23): 6071-6085, 2021 Dec.
Article En | MEDLINE | ID: mdl-34418236

It is commonly accepted that species should move toward higher elevations and latitudes to track shifting isotherms as climate warms. However, temperature might not be the only limiting factor determining species distribution. Species might move to opposite directions to track changes in other climatic variables. Here, we used an extensive occurrence data set and an ensemble modelling approach to model the climatic niche and to predict the distribution of the seven baobab species (genus Adansonia) present in Madagascar. Using climatic projections from three global circulation models, we predicted species' future distribution and extinction risk for 2055 and 2085 under two representative concentration pathways (RCPs) and two dispersal scenarios. We disentangled the role of each climatic variable in explaining species range shift looking at relative variable importance and future climatic anomalies. Four baobab species (Adansonia rubrostipa, Adansonia madagascariensis, Adansonia perrieri¸ and Adansonia suarezensis) could experience a severe range contraction in the future (>70% for year 2085 under RCP 8.5, assuming a zero-dispersal hypothesis). For three out of the four threatened species, range contraction was mainly explained by an increase in temperature seasonality, especially in the North of Madagascar, where they are currently distributed. In tropical regions, where species are commonly adapted to low seasonality, we found that temperature seasonality will generally increase. It is, thus, very likely that many species in the tropics will be forced to move equatorward to avoid an increase in temperature seasonality. Yet, several ecological (e.g., equatorial limit, or unsuitable deforested habitat) or geographical barriers (absence of lands) could prevent species to move equatorward, thus increasing the extinction risk of many tropical species, like endemic baobab species in Madagascar.


Adansonia , Climate Change , Ecosystem , Geography , Madagascar , Temperature
6.
Sci Rep ; 11(1): 13048, 2021 06 30.
Article En | MEDLINE | ID: mdl-34193882

Apex predators are threatened globally, and their local extinctions are often driven by failures in sustaining prey acquisition under contexts of severe prey scarcity. The harpy eagle Harpia harpyja is Earth's largest eagle and the apex aerial predator of Amazonian forests, but no previous study has examined the impact of forest loss on their feeding ecology. We monitored 16 active harpy eagle nests embedded within landscapes that had experienced 0 to 85% of forest loss, and identified 306 captured prey items. Harpy eagles could not switch to open-habitat prey in deforested habitats, and retained a diet based on canopy vertebrates even in deforested landscapes. Feeding rates decreased with forest loss, with three fledged individuals dying of starvation in landscapes that succumbed to 50-70% deforestation. Because landscapes deforested by > 70% supported no nests, and eaglets could not be provisioned to independence within landscapes > 50% forest loss, we established a 50% forest cover threshold for the reproductive viability of harpy eagle pairs. Our scaling-up estimate indicates that 35% of the entire 428,800-km2 Amazonian 'Arc of Deforestation' study region cannot support breeding harpy eagle populations. Our results suggest that restoring harpy eagle population viability within highly fragmented forest landscapes critically depends on decisive forest conservation action.

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