RESUMO
A critical step to design wildlife mitigating measures is the identification of roadkill hotspots. However, the effectiveness of mitigations based on roadkill hotspots depends on whether spatial aggregations are recurrent over time, spatially restricted, and most importantly, shared by species with diverse ecological and functional characteristics. We used a functional group approach to map roadkill hotspots for mammalian species along the BR-101/North RJ, a major road crossing important remnants of the Brazilian Atlantic Forest. We tested if functional groups present distinct hotspot patterns, and if they converge into the same road sectors, in that case, favoring optimal mitigating actions. Roadkill rates were monitored and recorded between October/2014 and September/2018 and species were classified into six functional groups based on their home range, body size, locomotion mode, diet, and forest-dependency. Hotspots along the roads were mapped for comparison of spatial patterns between functional groups. Results demonstrated that the roadkill index varied idiosyncratically for each functional group throughout the months and that no group presented seasonality. Seven hotspots were shared by two or more functional groups, highlighting the importance of these road stretches to regional mammal fauna. Two of the stretches are associated with aquatic areas extending from one side of the road to the other, and the remaining are connected to patches of native vegetation on both sides. This work brings a promising approach, yet hardly used in ecological studies on roads to analyze roadkill dynamics, assigning more importance to ecological instead of taxonomical characteristics, normally used to identify spatiotemporal patterns.
Assuntos
Animais Selvagens , Mamíferos , Animais , Brasil , FlorestasRESUMO
Loss of developmental stability can lead to deviations from bilateral symmetry (i.e. Fluctuating Asymmetry - FA), and is thought to be caused by environmental and genetic factors associated with habitat loss and stress. Therefore, levels of FA might be a valuable tool to monitor wild populations if FA serves as an indicator of exposure to stress due to impacts of habitat loss and fragmentation. In studies examining FA and habitat fragmentation, FA levels are often explained by loss of genetic variation, though few studies have addressed FA's use as indicator of environmental impact. Here, we investigated whether habitat loss, genetic variation, and/or inbreeding affect the developmental instability in Brazilian Atlantic forest populations of a Neotropical water rat (Nectomys squamipes). We sampled individuals from eight sites within Atlantic forest remnants with different amounts of available forest habitat and assessed FA levels with geometric morphometric techniques using adult mandibles. We used observed heterozygosity (Ho) and inbreeding coefficient (Fis), from seven microsatellite markers, as a proxy of genetic variation at individual and population levels. Populations were not significantly different for shape or size FA levels. Furthermore, interindividual variation in both shape and size FA levels and interpopulational differences in size FA levels were best explained by chance. However, habitat amount was negatively associated with both interpopulational variance and average shape FA levels. This association was stronger in populations living in areas with <28% of forest cover, which presented higher variance and higher average FA, suggesting that Nectomys squamipes might have a tolerance threshold to small availability of habitat. Our work is one of the first to use FA to address environmental stress caused by habitat loss in small mammal populations from a Neotropical biome. We suggest that shape FA might serve as a conservation tool to monitor human impact on natural animal populations.
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Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1-6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. Please cite this Data Paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.
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Necromys lasiurus is a generalist rodent that is thought to be the main reservoir of the Araraquara hantavirus, which causes Hantavirus Pulmonary Syndrome, in the Brazilian Cerrado savanna. This species occurs naturally in the open habitats of the Cerrado, Pantanal and Caatinga biomes, where it often occurs at high densities, although the distribution of the species has recently been observed expanding into the Brazilian state of Rio de Janeiro. This study aimed to map the occurrence of N. lasiurus within the Atlantic Forest of Rio de Janeiro state and discuss the potential role of the species as a reservoir of the Araraquara hantavirus in these areas. The study was based on a comprehensive literature search and four expeditions for the collection of specimens in the state of Rio de Janeiro. The data were used to predict the distribution of N. lasiurus, confirm the distribution of the species in the state, and detect the rates of hantavirus infection in these rodents. Necromys lasiurus has been recorded at 16 localities in 10 municipalities of Rio de Janeiro state. The relative abundance of N. lasiurus was low at all localities, except for the REBIO Poço das Antas and APA-BRSJ, two protected areas. Necromys lasiurus was associated primarily with landscapes dominated by farmland (plantations or pasture) at relatively low altitudes in the vicinity of bodies of water. A total of 204 serum samples were collected, but none were reactive for hantavirus. The distribution of N. lasiurus is expanding into many areas of the anthropogenic matrix, but it is not usually either abundant or dominant in these areas. The relatively reduced abundance of N. lasiurus in Rio de Janeiro and the lack of infection in all the areas investigated indicate that it is unlikely to be a reservoir of hantavirus in this region in the near future.
Assuntos
Infecções por Hantavirus/veterinária , Orthohantavírus , Roedores/virologia , Animais , Brasil/epidemiologia , Reservatórios de Doenças , FlorestasRESUMO
The northern coast of the state of Rio de Janeiro harbors the largest coastal sandy plains (restingas) of southeastern Brazil, severely threatened due to recent human occupation. In this context, mammal inventories becomes urgent to support biodiversity conservation and management policies. This paper aims to update the knowledge on the mammalian species richness of Restinga de Jurubatiba National Park by analyzing pellets of the Barn owl Tyto furcata. The analyses of 4745 mammalian bone fragments (1739 individuals) revealed the occurrence of 17 species belonging to the orders Rodentia (9 spp.), Didelphimorphia (2 spp.) and Chiroptera (6 spp.). The rodents Mus musculus and Cerradomys goytaca accounted for 77.2% of the total individuals preyed, suggesting that the Barn owl hunts in both disturbed and natural open shrub formations. A compilation of previous records, together with those provided in the present study, indicates the occurrence of 44 species of mammals in the Restinga de Jurubatiba National Park, of which six (13.6%) were exclusively detected in pellets. These new records include species adapted to open formations of the interior of Brazil that were not previously reported in restingas on the basis of voucher-specimens, such as the rodents Necromys lasiurus and Calomys tener, the latter being recorded for the first time in the littoral of Rio de Janeiro state. This study underscores the importance of owl pellet analysis as a complementary and indispensable method for inventorying mammals. The results highlight the Restinga de Jurubatiba National Park as one of the restingas in Southeastern Brazil with the highest number of mammal species.
O litoral norte do estado do Rio de Janeiro possui a maior planície deltaica recoberta por restingas do sudeste brasileiro, porém sob intensa ameaça devido è ocupação humana recente. Neste contexto, a realização de inventários torna-se urgente para fortalecer políticas de manejo e conservação ambiental. Esse trabalho teve como objetivo complementar inventários mastofaunísticos do Parque Nacional da Restinga de Jurubatiba através da utilização de pelotas da coruja suindara Tyto furcata. A análise de 4745 fragmentos ósseos de mamíferos (1739 indivíduos) revelou a ocorrência de 17 espécies pertencentes ès ordens Rodentia (9 spp.), Didelphimorphia (2 spp.) e Chiroptera (6 spp.). Os roedores Mus musculus e Cerradomys goytaca foram responsáveis por 77,2% do total de indivíduos predados, sugerindo que a suindara caça tanto em ambientes peridomiciliares perturbados como em formações naturais arbustivas da restinga. A compilação de registros anteriores com os fornecidos pelo presente estudo indica a ocorrência de 44 espécies de mamíferos no Parque Nacional da Restinga de Jurubatiba, dentre as quais seis (13.6%) foram exclusivamente detectadas em pelotas. Dentre estes novos registros, destaca-se a presença de espécies adaptadas a formações abertas do interior do Brasil que não tinham sua ocorrência documentada em restingas a partir de espécimes-testemunho, como os roedores Necromys lasiurus e Calomys tener, esta última registrada pela primeira vez no litoral do estado do Rio de Janeiro. Esse estudo corrobora a importância das análises de pelotas de coruja como método complementar e imprescindível em inventários de mamíferos, além de destacar o Parque Nacional da Restinga de Jurubatiba como uma das restingas mais ricas em espécies de mamíferos do sudeste brasileiro.
RESUMO
Recent taxonomic studies on Neotropical mammals have benefited from the use of genetic data to unravel and recognize species diversity in a number of genera, including the Atlantic forest endemic genus Delomys. However, the success of this approach depends on ability to link genetically identified lineages to species names based on voucher specimens that lack genetic data. Cytogenetic studies in the Atlantic forest endemic rodent genus Delomys have revealed two widespread karyotypes, 2n=72/FN=90 and 2n=82/FN=80, which have been respectively ascribed to Delomys sublineatus (Thomas, 1903) and D. dorsalis (Hensel, 1872). More recently, a third karyotype, 2n=82/FN=86, reported from specimens collected on two montaintops in southeastern Brazil, was interpreted as evidence for a third species, D. collinus Thomas, 1917. This nominal form had originally been described as a subspecies of D. dorsalis from Itatiaia, one of the mountain ranges where the third karyotype was later detected. The detection of two sympatric karyotypes at the type locality of D. collinus in the Itatiaia mountain range, Southeastern Brazil, prompted a reevaluation of the association of karyomorphs and species names. In this paper, we assessed the congruence of molecular (cytochrome b), cytogenetic and morphological characters, to diagnose the species in the genus, including data from recently collected series and type specimens. Our results indicate that the genetic and morphological patterns are largely congruent with the recognition of three species, each of which is karyotypically and morphologically diagnosable. Our morphological analyses of sympatric samples from Itatiaia refute the former association of the 2n=82/FN=86 karyotype with the holotype of D. dorsalis collinus (which is more similar to D. dorsalis with 2n=82/FN=80). Instead, we recognize and describe a new species for the 2n=82/FN=86 populations from the highest altitudinal zones of the Itatiaia and Caparaó mountains. The geographical variation in D. dorsalis is also explored and the status of D. d. collinus is discussed in the light of the molecular and morphological evidence. Finally, we discuss biogeographic hypotheses concerning the disjunct distributions of D. dorsalis and the new species.