Átilla Colombo Ferreguetti

Density, occupancy, and activity pattern of two sympatric deer (Mazama) in the Atlantic Forest, Brazil

The red brocket (Mazama americana) and gray brocket deer (Mazama gouazoubira) are sympatric in the Atlantic Forest and present a number of ecological similarities in their diet and habitat use, although interspecific competition in these species is poorly understood. This study aimed to compare abundance and produce evidence of niche partitioning between these species. We estimated population density, activity patterns, habitat occupancy, and detection probabilities for the 2 species in a large remnant of the Atlantic Forest of Espírito Santo, Brazil. Abundance was estimated using the distance sampling technique, and occupancy, detectability, and activity patterns were assessed using camera-trap monitoring at 39 sample sites over a 1-year period. During surveys, we obtained 44 sightings of M. americana and 74 of M. gouazoubira, with 199 records in which the species was not discriminated. We applied a correction for the unidentified sightings to avoid underestimating density. The corrected population size estimates were 3,668 individuals (confidence interval [CI] 95%: 2,989–4,601) for M. americana and 6,701 (CI 95%: 5,857–7,667) for M. gouazoubira. Occupancy probability for M. americana was best described by the large trees density (diameter at breast height > 50 cm) and the edge forest distance, while M. gouazoubira did not present any habitat preferences based on the covariates used for modeling. M. americana was mostly nocturnal, whereas M. gouazoubira was active mainly during the day. We conclude that, despite the abundance of these sympatric species, and their occupation of the same habitats, they may avoid competing for habitat and feeding resources through differences in their activity patterns.

Density, occupancy, and detectability of lowland tapirs, Tapirus terrestris, in Vale Natural Reserve, southeastern Brazil

The lowland tapir (Tapirus terrestris, Linnaeus 1758) is one of the surviving members of the Neotropical megafauna. In Brazil, lowland tapirs are considered vulnerable according to the IUCN Red List of Threatened Species and endangered within the Atlantic Rain Forest biome. We aimed to provide the 1st estimates of density and population size for T. terrestris for Vale Natural Reserve (VNR). We predicted the relationships of 6 covariates to habitat occupancy. Density was estimated by the use of distance-sampling techniques, while occupancy, detectability, and activity patterns were assessed with camera-trap monitoring at 39 sample sites over a 1-year period. Density for T. terrestris was 0.8±0.2 lowland tapirs/km2 and population size was 200±33 individuals. Occupancy probability was described by 2 covariates (density of palm trees and distance to water resources) and detectability by those same 2 covariates plus 2 more (distance to road and density of poaching). The species showed the 3 highest peaks of activity at 1900, 2300, and 0400 h. We concluded that VNR still harbors a viable population of lowland tapirs. However, anthropic impacts in the reserve such as poaching and road kills could already be directly affecting the lowland tapir population and producing indirect effects for the whole ecosystem. Results presented herein can be a starting point to support future work in the region and to make predictions regarding the ecosystem relationships, management, and conservation of lowland tapirs.

You can’t run but you can hide: the negative influence of human presence on mid-sized mammals on an Atlantic island

Here, we report the results of a camera-trapping survey of mid-sized (1–50 kg) mammals on an oceanic Atlantic forest island in Brazil. Despite 80% of the island being formally reserved for conservation, the island’s northern areas support a small, but rapidly growing human population that we expected would disturb the mammals and their foraging and movement behaviors. Hunting activities are also more frequent and severe on the north side of the island, closer to the villages. We tested the following hypothesis: the probability of occupancy, detectability, and abundance of mid-sized mammals will be higher in less-disturbed areas on southern parts of the island than in more-disturbed areas to the north. Ordination using multi-dimensional scaling (MDS) highlighted that mammal assemblages were differentiated between the northern and southern slope areas, and regression analyses showed MDS scores to be associated strongly with an index of human population density. Occupancy models for Didelphis aurita, Dasypus novemcinctus, Dasyprocta leporina, and Cuniculus paca showed no effect of habitat covariates, but there were marked effects of human activity impact on the detection probability of all species, except D. aurita. Species detections and local abundances were higher in the less disturbed southern parts of the island. Our results support the notion that mid-sized mammals will change their movement and foraging behaviors as a function of human activities, even inside reserved, protected areas.

The rusty-margined guan (Penelope superciliaris) in the Brazilian Atlantic rain forest: density, population size, activity and habitat use

Abstract Context. Population estimation and monitoring are important tools for the support of programs and actions of conservation for most wildlife species, including birds. For validation of such support, a set of reliable, consistent and comparable parameter estimates is essential (through systematic monitoring over time), in addition to studies on ecological aspects of the species. Aims. In this study, our aim was to analyse the population of Penelope superciliaris in the Vale Natural Reserve (VNR), located in north-eastern Espírito Santo, Brazil, providing estimates of density, population size and activity. We also analysed occupancy and detectability of the species, relating them to six covariates (distance from forest edge, water and road, as well as poaching intensity, canopy cover and understorey cover) based on previous knowledge of the ecology of rusty-margined guan. Methods. We used line-transect surveys to estimate density and abundance, and camera traps to estimate habitat use by P. superciliaris, using the occupancy modelling approach. Key results. Estimated density for P. superciliaris was 2.5 ± 1.0 groups per km2 with a group size of 6.0 ± 2.0 individuals, and estimated population size for the entire VNR was 3544 ± 495 individuals. Occupancy by P. superciliaris was best described by three covariates: (1) distance to road; (2) distance to water; and (3) poaching intensity. Detectability was affected by two covariates: (1) understorey cover; and (2) poaching intensity. Conclusions. Our results provide the first information on density, habitat use and activity of P. superciliaris in the VNR. We concluded that P. superciliaris is active diurnally, especially during morning and late afternoon, prefers areas near water sources in denser forests and tends to avoid areas with habitat modification and intense poaching activity. Implications. Our data highlight the impact of poaching on the species and can be useful as a baseline for future studies and Cracid conservation plans.

Density, habitat use, and daily activity patterns of the Red-rumped Agouti (Dasyprocta leporina) in the Atlantic Forest, Brazil

ABSTRACT The Red-rumped Agouti (Dasyprocta leporina, Linnaeus, 1758) is considered common in areas where it occurs, and it is listed as Least Concern status in the IUCN red list; however, in recent decades it has been negatively affected by habitat loss and hunting. The conservation status needs to be updated since no recent studies have been conducted in the Atlantic Forest. Therefore, we aimed to estimate the density, occupancy and detectability of D. leporina in one of the larger Atlantic Forest remnants in Espírito Santo, Brazil, the Vale Natural Reserve (VNR). We surveyed four line transects between April 2013 and May 2014 to estimate density and abundance. To model occupancy probability, as well as to document activity pattern, we selected 39 sampling sites with one camera-trap each. Estimated density was 21 ± 3 individuals km–2 and estimated population size was 4935 ± 368 individuals. Occupancy increases with palm density, distance from forest edge, and canopy cover. Occupancy and detectability decreases with distance from water resources. Detectability increases with palm density. The results presented herein can be a starting point to support future action plans for the species, making predictions regarding the ecosystem and management and conservation of D. leporina.

Use of polyvinyl chloride pipes (PVC) as potential artificial shelters for amphibians in a coastal plain forest of southeastern Brazil

We studied the use of polyvinil chloride pipes (PVC pipes) by frogs as artificial shelters in a Coastal Plain forest in the Vale Natural Reserve, north of Espírito Santo state, southeastern Brazil from June 2015 to May 2016. We used 14 plots distributed in the Coastal Plain Forest following the RAPELD methodology of sampling. The frogs were sampled in transects along the plots, using the active search method, with visual and auditory sampling. We recorded two species of frogs (Aparasphenodon brunoi and Scinax argyreornatus) using PVC pipes as shelters in the plots in the Forest. Of the 468 PVC pipes established along plots, 38 of them (8.1%) were used as shelter by the frogs. For both frog species, about 33% of microhabitats used in the forest were the interior of PVC pipes. We concluded that the PVC pipes might constitute artificial shelters for at least two of the frog species living in the community of the Coastal Plain Forest, potentially being of relevance in conservation programs. In altered areas and those in which there has been the loss of types of microhabitats, the addition of these PVC pipes as artificial shelters may represent additional and complementary microhabitats to keep or increase the population stocks of arboreal and semi-arboreal frog species and having a size that allow them entering the shelter. These artificial shelters can play an important role in conservation of these frogs in fragmented areas where the availability of the microhabitats of these frog species were locally reduced.

Spatial distribution of buffy-tufted-ear (Callithrix aurita) and invasive marmosets (Callithrix spp.) in a tropical rainforest reserve in southeastern Brazil

We investigated the spatial distribution of native and invasive marmoset species (Callithrix), as well as their hybrids, in the Serra dos Órgãos National Park (PARNASO) and surrounding area in Rio de Janeiro state, Brazil. To estimate occupancy and the detection probability, we surveyed 56 sites within the park and 52 sites outside its limits using vocal playbacks, as well as by interviewing local residents in the surrounding area. We estimated the occupancy and detection probability of Callithrix aurita and the observed groups composed of Callithrix jacchus, Callithrix penicillata, and their hybrids. We also recorded the presence or absence of mixed groups of native and exotic species, and their hybrids. We recorded similar occupancy rates and detection probabilities for both native and invasive species within the national park. C. aurita was found more often within the areas of the park located furthest from access roads and with the least human interference, while invasive species were more likely to be found along the edge of the park and in areas with greater human interference. In the area surrounding the park, invasive marmosets were recorded at seven sites, and a mixed group of native and invasive marmosets was observed at one site, but non‐hybrid C. aurita groups were not recorded. The occupancy probability of C. aurita in the study area is relatively low, which may indicate a low population density, with groups restricted to a small region within the PARNASO in the proximity of groups of invasive marmosets.

Differencial efficiency of two sampling methods in capturing non-volant small mammals in an area in eastern Amazonia

This study was the first to evaluate the efficiency of trapping methods in the study of small mammals in the Carajas National Forest, southeastern Brazilian Amazon. It is an area with a unique vegetation type (metalofilic savannah or Canga). The aims of this study were to compare the efficiency of two trapping methods (i.e. live-traps and pitfalls), the bait types used, and evaluate if trapping success varied seasonally. We used four sampling grids, each with six parallel transects. The trap effort for live-traps and pitfalls was 51,840 trap*nights and 10,800 bucket*nights, respectively. We used three types of bait: a paste of peanut butter and sardines, bacon, and bananas. We placed one type of bait in each trap, alternating between points. We recorded 26 species of small mammals, 11 from the order Didelphimorphia and 15 from the order Rodentia. Pitfalls captured a higher number of species compared with live-traps. The capture rate, the mortality rate and the quantity of juveniles and adults did not differ significantly between methods. Capture rate for pitfalls differed significantly between seasons. The majority of species were captured by a single method. Species were equally attracted to the traps regardless of the type of bait used. Some of our results differed significantly from other studies in Amazonia and such variation should be taken into account when designing survey methods for Amazonian small mammals.

Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon.

The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or “Canga”, which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (<< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively affect sensitive wildlife species.

Non-volant mammals from Domingos Martins municipality, state of Espírito Santo, southeastern Brazil

The goal of this study was to contribute to the knowledge of the mammals in the state of Espirito Santo, presenting a list to the Domingos Martins municipality. Regarding the mammals inventory, data obtained from field work and through digital search by species deposited in scientific collections and available on the SpeciesLink database were used. We recorded 47 non-volant mammal species, including 12 endemic in the Atlantic Forest and nine listed as threatened. Domingos Martins, despite being undersampled when compared to other mammals inventories in the state of Espirito Santo, represents 57% of the terrestrial mammals listed in the state. This shows the potential of the municipality in relation to mammal conservation, not only in the state, but also for Atlantic Forest biome.