81 research outputs found
Brown howler monkey: alouatta guariba Humboldt, 1812
Alouatta guariba is endemic to the Atlantic Forest in eastern Brazil and northeast Argentina. In the south, its distribution is limited by the Camaquã river basin (Printes et al. 2001) and to the north by the Paraguaçu river in the state of Bahia (Gregorin 2006; Neves et al. 2018). The western boundary is marked by the limits of the Atlantic Forest. It occurs in the Brazilian states of Bahia, Espírito Santo, Rio de Janeiro, Minas Gerais, São Paulo, Paraná, Santa Catarina and Rio Grande do Sul (Mendes et al. 2008, Bicca-Marques et al. 2018). In Argentina the species is limited to the province of Misiones (Agostini et al. 2017).Fil: Buss, Gerson. Centro Nacional de Pesquisa e Conservação dos Primatas; BrasilFil: Oklander, Luciana Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Bicca Marques, Júlio César. Pontificia Universidad Catolica de Parana. Escola de Ciencias Da Vida.; BrasilFil: Hirano, Zelinda B.. Universidade Regional de Blumenau; BrasilFil: Chaves, Oscar M.. Pontificia Universidad Catolica de Parana. Escola de Ciencias Da Vida.; BrasilFil: Mendes, Sergio L.. Instituto Nacional da Mata Atlântica; BrasilFil: Neves, Leonardo G.. Universidade Estadual de Santa Cruz; BrasilFil: Melo, Fabiano R.. Universidade Federal de Viçosa.; BrasilFil: Rylands, Anthony B.. Wildlife Conservation Society; Estados UnidosFil: Jerusalinsky, Leandro. Centro Nacional de Pesquisa e Conservação dos Primatas Brasileiros; Brasi
Wild dogs at stake: deforestation threatens the only Amazon endemic canid, the short-eared dog (Atelocynus microtis)
The persistent high deforestation rate and fragmentation of the Amazon forests are the main threats to their biodiversity. To anticipate and mitigate these threats, it is important to understand and predict how species respond to the rapidly changing landscape. The short-eared dog Atelocynus microtis is the only Amazon-endemic canid and one of the most understudied wild dogs worldwide. We investigated short-eared dog habitat associations on two spatial scales. First, we used the largest record database ever compiled for short-eared dogs in combination with species distribution models to map species habitat suitability, estimate its distribution range and predict shifts in species distribution in response to predicted deforestation across the entire Amazon (regional scale). Second, we used systematic camera trap surveys and occupancy models to investigate how forest cover and forest fragmentation affect the space use of this species in the Southern Brazilian Amazon (local scale). Species distribution models suggested that the short-eared dog potentially occurs over an extensive and continuous area, through most of the Amazon region south of the Amazon River. However, approximately 30% of the short-eared dog's current distribution is expected to be lost or suffer sharp declines in habitat suitability by 2027 (within three generations) due to forest loss. This proportion might reach 40% of the species distribution in unprotected areas and exceed 60% in some interfluves (i.e. portions of land separated by large rivers) of the Amazon basin. Our local-scale analysis indicated that the presence of forest positively affected short-eared dog space use, while the density of forest edges had a negative effect. Beyond shedding light on the ecology of the short-eared dog and refining its distribution range, our results stress that forest loss poses a serious threat to the conservation of the species in a short time frame. Hence, we propose a re-assessment of the short-eared dog's current IUCN Red List status (Near Threatened) based on findings presented here. Our study exemplifies how data can be integrated across sources and modelling procedures to improve our knowledge of relatively understudied species
Canine visceral leishmaniasis: study of methods for the detection of IgG in serum and eluate samples
Drivers of habitat availability for terrestrial mammals: Unravelling the role of livestock, land conversion and intrinsic traits in the past 50 years
The global decline of terrestrial species is largely due to the degradation, loss and fragmentation of their habitats. The conversion of natural ecosystems for cropland, rangeland, forest products and human infrastructure are the primary causes of habitat deterioration. Due to the paucity of data on the past distribution of species and the scarcity of fine-scale habitat conversion maps, however, accurate assessment of the recent effects of habitat degradation, loss and fragmentation on the range of mammals has been near impossible. We aim to assess the proportions of available habitat within the lost and retained parts of mammals' distribution ranges, and to identify the drivers of habitat availability. We produced distribution maps for 475 terrestrial mammals for the range they occupied 50 years ago and compared them to current range maps. We then calculated the differences in the percentage of 'area of habitat' (habitat available to a species within its range) between the lost and retained range areas. Finally, we ran generalized linear mixed models to identify which variables were more influential in determining habitat availability in the lost and retained parts of the distribution ranges. We found that 59% of species had a lower proportion of available habitat in the lost range compared to the retained range, thus hypothesizing that habitat loss could have contributed to range declines. The most important factors negatively affecting habitat availability were the conversion of land to rangeland and high density of livestock. Significant intrinsic traits were those related to reproductive timing and output, habitat breadth and medium body size. Our findings emphasize the importance of implementing conservation strategies to mitigate the impacts caused by human activities on the habitats of mammals, and offer evidence indicating which species have the potential to reoccupy portions of their former range if other threats cease to occur.This study investigates the impact of habitat degradation on terrestrial mammal species. By comparing historic and current distribution maps for 475 species, we found that 59% of them have less available habitat in their lost ranges, suggesting habitat loss contributed to range declines. Factors like land conversion to rangeland and high livestock density negatively affected habitat availability. Intrinsic traits such as reproductive timing, habitat breadth and medium body size also played a role. The study underscores the need for conservation efforts to mitigate human-induced habitat threats and identifies species that could potentially reclaim lost range if threats are addressed.imag
Economic viability of the use of crude glycerin supplements in diets for grazing crossbred calves
Extração de DNA a partir de sangue humano coagulado para aplicação nas técnicas de genotipagem de antígenos leucocitários humanos e de receptores semelhantes à imunoglobulina
Análise discriminante de solos sob diferentes usos em área de Mata Atlântica a partir de atributos da matéria orgânica
Factors influencing terrestriality in primates of the Americas and Madagascar
Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (bodymass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use
- …