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1.
An Acad Bras Cienc ; 95(suppl 2): e20220746, 2023.
Article in English | MEDLINE | ID: mdl-38126433

ABSTRACT

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.


Subject(s)
Conservation of Natural Resources , Ecosystem , Humans , Conservation of Natural Resources/methods , Socioeconomic Factors , Brazil , Rural Population , Agriculture
2.
Sci Rep ; 11(1): 22808, 2021 11 23.
Article in English | MEDLINE | ID: mdl-34815416

ABSTRACT

Conservation of carnivores involves finding solutions to minimize habitat loss and human-wildlife conflict. Understanding the nature of land-use economics can allow us to mitigate both threats. In the Pantanal, the two main economic activities are cattle ranching and ecotourism, each of which directly and indirectly affect the persistence of jaguars (Panthera onca). To understand how the geography of these economic activities is related to jaguar populations, we developed a jaguar distribution model (JDM), livestock density model, and ecotourism lodge density model for the Pantanal. Due to the recent wildfires within the Pantanal, we also assess the impact of burnt areas that are suitable for jaguars, cattle ranching, and tourism. Our JDM indicate that 64% of the Pantanal holds suitable habitat for jaguars. However, jaguar habitat suitability was positively correlated with ecotourism, but negatively correlated with areas most suitable for intensive cattle-ranching. This demonstrates a biome-wide scenario compatible with jaguar conservation. Of particular concern, recent wildfires overlap most suitable areas for jaguars. If wildfires become increasingly frequent, this would represent a serious threat to jaguars and many other wildlife populations. We emphasize the global importance of the Pantanal wetland ecoregion as a key stronghold for long-term jaguar conservation.


Subject(s)
Conservation of Natural Resources/economics , Ecosystem , Panthera/physiology , Population Dynamics , Tourism , Urbanization/trends , Wetlands , Animals , Cattle , Geography
3.
J Anim Ecol ; 90(12): 2729-2743, 2021 12.
Article in English | MEDLINE | ID: mdl-34553786

ABSTRACT

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.


Subject(s)
Chiroptera , Animals , Biodiversity , Diet , Ecosystem , Phylogeny
4.
Sci Rep ; 10(1): 14750, 2020 09 15.
Article in English | MEDLINE | ID: mdl-32934299

ABSTRACT

Neotropical mammal diversity is currently threatened by several chronic human-induced pressures. We compiled 1,029 contemporary mammal assemblages surveyed across the Neotropics to quantify the continental-scale extent and intensity of defaunation and understand their determinants based on environmental covariates. We calculated a local defaunation index for all assemblages-adjusted by a false-absence ratio-which was examined using structural equation models. We propose a hunting index based on socioenvironmental co-variables that either intensify or inhibit hunting, which we used as an additional predictor of defaunation. Mammal defaunation intensity across the Neotropics on average erased 56.5% of the local source fauna, with ungulates comprising the most ubiquitous losses. The extent of defaunation is widespread, but more incipient in hitherto relatively intact major biomes that are rapidly succumbing to encroaching deforestation frontiers. Assemblage-wide mammal body mass distribution was greatly reduced from a historical 95th-percentile of ~ 14 kg to only ~ 4 kg in modern assemblages. Defaunation and depletion of large-bodied species were primarily driven by hunting pressure and remaining habitat area. Our findings can inform guidelines to design transnational conservation policies to safeguard native vertebrates, and ensure that the "empty ecosystem" syndrome will be deterred from reaching much of the New World tropics.


Subject(s)
Extinction, Biological , Mammals/anatomy & histology , Animals , Biodiversity , Central America , Conservation of Natural Resources , Forests , Human Activities , Humans , Mammals/physiology , Population Dynamics/statistics & numerical data , South America , Tropical Climate
5.
PLoS One ; 15(8): e0229277, 2020.
Article in English | MEDLINE | ID: mdl-32817698

ABSTRACT

Human activities are changing landscape structure and function globally, affecting wildlife space use, and ultimately increasing human-wildlife conflicts and zoonotic disease spread. Capybaras (Hydrochoerus hydrochaeris) are linked to conflicts in human-modified landscapes (e.g. crop damage, vehicle collision), as well as the spread and amplification of Brazilian spotted fever (BSF), the most human-lethal tick-borne disease in the world. Even though it is essential to understand the link between capybaras, ticks and BSF, many knowledge gaps still exist regarding the effects of human disturbance in capybara space use. Here, we analyzed diurnal and nocturnal habitat selection strategies of capybaras across natural and human-modified landscapes using resource selection functions (RSF). Selection for forested habitats was higher across human-modified landscapes, mainly during day- periods, when compared to natural landscapes. Across natural landscapes, capybaras avoided forests during both day- and night periods. Water was consistently selected across both landscapes, during day- and nighttime. Distance to water was also the most important variable in predicting capybara habitat selection across natural landscapes. Capybaras showed slightly higher preferences for areas near grasses/shrubs across natural landscapes, and distance to grasses/shrubs was the most important variable in predicting capybara habitat selection across human-modified landscapes. Our results demonstrate human-driven variation in habitat selection strategies by capybaras. This behavioral adjustment across human-modified landscapes may be related to increases in A. sculptum density, ultimately affecting BSF.


Subject(s)
Ecosystem , Rodentia/psychology , Animals , Animals, Wild , Brazil , Environment , Grassland , Host-Parasite Interactions/physiology , Humans , Rocky Mountain Spotted Fever/epidemiology , Ticks , Water , Zoonoses
6.
Sci Rep ; 10(1): 10594, 2020 06 29.
Article in English | MEDLINE | ID: mdl-32601315

ABSTRACT

The local, global or functional extinction of species or populations of animals, known as defaunation, can erode important ecological services in tropical forests. Many mutualistic interactions, such as seed dispersal of large seeded plants, can be lost in large continuous forests due to the rarity of large-bodied mammalian frugivores. Most of studies that try to elucidate the effects of defaunation on seed dispersal focused on primates or birds, and we lack a detailed understanding on the interactions between ground-dwelling fauna and fleshy fruits. Using camera traps in forest areas with different degrees of defaunation, we described the organization of frugivory networks involving birds, mammals and plants. We recorded 375 frugivory interactions between 21 frugivores and 150 fruiting trees of 30 species of fleshy fruit plants in six sites in continuous Atlantic forest of Brazil. We found that small frugivores-particularly small rodents and birds-were responsible for 72% of the events of frugivory. Large frugivores, such as tapirs and peccaries, were responsible for less than 21% of frugivory events. Our results indicate that the interactions between flesh fruiting plants and frugivores are dominated by small frugivores, an indication of a functional loss of large frugivores in this endangered biome.


Subject(s)
Ecosystem , Feeding Behavior/physiology , Seed Dispersal/physiology , Animals , Biodiversity , Birds , Brazil , Conservation of Natural Resources/methods , Ecology , Forests , Fruit , Mammals , Plants , Seeds/growth & development , Trees , Vertebrates
7.
J Med Entomol ; 57(1): 308-311, 2020 01 09.
Article in English | MEDLINE | ID: mdl-31504641

ABSTRACT

The bacterium Rickettsia rickettsii is the agent of Brazilian spotted fever (BSF), a highly fatal disease that is transmitted in Brazil mainly by the tick Amblyomma sculptum Berlese, which uses capybaras (Hydrochoerus hydrochaeris Linnaeus) as major hosts. In 2015, we captured nine capybaras in a BSF-endemic area of southeastern Brazil. From each capybara, we collected blood sera that were tested through the immunofluorescence assay using Rickettsia spp. antigens, and A. sculptum ticks, processed for isolation of R. rickettsii through guinea pig inoculation. All capybaras (100%) were seroreactive to Rickettsia spp., with highest titers to R. rickettsii. A total of 166 A. sculptum ticks were macerated and inoculated into nine guinea pigs, from which only one presented high fever and seroconverted to R. rickettsii. Blood from this febrile animal was inoculated into additional guinea pigs (guinea pig passages), which also became febrile and seroconverted, or when euthanized during the fever period, their internal organs (spleen, lung) were shown to contain R. rickettsii DNA. The present rickettsial isolate has been maintained cryopreserved as infected guinea pig organs. There was at least one R. rickettsii-infected tick among the 166 macerated ticks, giving a minimal infection rate of 0.6% (1/166). This infection rate is within the range of previous studies, which reported that only 0.05% to at most 1.28% A. sculptum ticks were infected by R. rickettsii in other BSF-endemic areas. These low infection rates support the low incidence of BSF, despite of A. sculptum being the most frequent human-biting tick in southeastern Brazil.


Subject(s)
Ixodidae/microbiology , Rickettsia rickettsii/isolation & purification , Rocky Mountain Spotted Fever/veterinary , Rodent Diseases/epidemiology , Rodentia , Animals , Brazil/epidemiology , Female , Incidence , Male , Nymph , Rocky Mountain Spotted Fever/epidemiology , Rocky Mountain Spotted Fever/microbiology , Rodent Diseases/microbiology
8.
Animals (Basel) ; 9(6)2019 Jun 13.
Article in English | MEDLINE | ID: mdl-31200544

ABSTRACT

Wildlife living within urban ecosystems have to adapt or perish. Red-legged Seriema, a large terrestrial bird, are rare in urban ecosystems, however, they have been reported in a medium-sized Brazilian city. We investigated the reasons for this occurrence as well as their behavior. We assessed the distribution of Seriemas (including fledglings), free-ranging cats, and cat-feeding points provided by humans, and past records of Seriemas in the study area. We discovered that Seriemas are sharing spatial resources with cats without apparent conflicts, and intraspecific competition was important to define the spatial distribution of Seriemas. This species is able to use human-made structures to improve territory defense and opportunistic foraging. Direct and indirect human food provisioning is helping them to survive in the studied area, but is also facilitating the domestication process, which may cause future conflicts with humans and cats. Although Seriemas have inhabited the studied urban area for years, they are still adapting their behaviors for urban life, as they have not yet perceived the dangers of automotive traffic. Our study corroborates that wild species may adapt to urban areas driven by human contact, but it also acts as a trap for the adaptive process.

9.
PeerJ ; 5: e4071, 2017.
Article in English | MEDLINE | ID: mdl-29259840

ABSTRACT

BACKGROUND: Since 1996, when Vivo questioned how many species of mammals occur in Brazil, there has been a huge effort to assess this biodiversity. In this contribution, we present new records for rare species of the sigmodontine rodent genera Rhagomys and Neusticomys previously unknown to Brazilian Amazon. We provided detailed information on the morphologic variation to allow the proper identification of these species. We also furnished updated information on their collection, aiming to establish hypothesis of their geographic distribution, based on SDM's, aiming to hypothesize potential occurrence areas for these species. METHODS: Rodent specimens were sampled in separate inventories in two sites of Rondônia State (Hydroelectric Dam Jirau and Parque Nacional de Pacaás Novos) and one site in Pará State (Pacajá), Brazil, and were compared to specimens from museum collections to apply appropriate names. The SDM were conducted using two algorithms for rare species, MaxEnt and randomForest (RF), and were based on seven localities for Rhagomys, and 10 for Neusticomys. RESULTS: All specimens were collected with pitfall traps. One specimen of genus Rhagomys was trapped in the Hydroelectric Dam Jirau. We identified this specimen as R. longilingua, and the SDM species indicates suitable areas for its occurrence at high elevations near on the Andes and lowlands of Amazon Basin to the South of the Rio Amazonas. Two specimens of Neusticomys were recorded, and we identified the specimen from Pacaás Novos as N. peruviensis, with SDM suggesting main areas of occurrence on Western Amazon. We applied the name N. ferreirai to the specimen from Pacajá, with SDM recovering suitable areas in Eastern Amazon. DISCUSSION: We reinforced the importance of pitfall traps on the study of Neotropical rodents. We described morphologic variation within and among all species that do not invalidate their specific status, but in the near future a re-evaluation will be mandatory. The new records extended the species distribution considerably. SDM was successful to predict their distributions, as the two algorithms presented important differences in range size recovered by the models that can be explained by differences in the thresholds used for the construction of the models. Most suitable areas coincide with the areas facing most of the deforestation in Amazon. We added two rare species of sigmodontine rodents to the list of Brazilian Mammals, which now comprises 722 species (or 775 valid nominal taxa). Although more information is available than in 1996, it is essential that mammal experts maintain inventory and revisionary programs to update and revise this information. This is even more important, as changes in Brazilian environmental legislation are being discussed, suggesting reduced need for environmental impact reports prior to beginning commercial enterprises, resulting in the loss of information about native biodiversity in the affected areas.

10.
Sci Rep ; 6: 37147, 2016 11 16.
Article in English | MEDLINE | ID: mdl-27849006

ABSTRACT

The jaguar is the top predator of the Atlantic Forest (AF), which is a highly threatened biodiversity hotspot that occurs in Brazil, Paraguay and Argentina. By combining data sets from 14 research groups across the region, we determine the population status of the jaguar and propose a spatial prioritization for conservation actions. About 85% of the jaguar's habitat in the AF has been lost and only 7% remains in good condition. Jaguars persist in around 2.8% of the region, and live in very low densities in most of the areas. The population of jaguars in the AF is probably lower than 300 individuals scattered in small sub-populations. We identified seven Jaguar Conservation Units (JCUs) and seven potential JCUs, and only three of these areas may have ≥50 individuals. A connectivity analysis shows that most of the JCUs are isolated. Habitat loss and fragmentation were the major causes for jaguar decline, but human induced mortality is the main threat for the remaining population. We classified areas according to their contribution to jaguar conservation and we recommend management actions for each of them. The methodology in this study could be used for conservation planning of other carnivore species.


Subject(s)
Biodiversity , Forests , Panthera/physiology , Animals , Population Dynamics , South America
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