Marcelo Passamani

Neotropical forest expansion during the last glacial period challenges refuge hypothesis

Significance The tropical forests of South America are among the most diverse and unique habitats in the world in terms of plant and animal species. One of the most popular explanations for this diversity and endemism is the idea that forests retracted and fragmented during glacial periods, forming ecological refuges, surrounded by dry lands or savannas. These historically stable forest refuges would have been responsible for maintaining the pattern of diversity and endemism observed today. Here, we show that the Atlantic Forest of eastern South America probably expanded, rather than contracted, during the last glacial period. In addition, the emerged Brazilian continental shelf played a major, yet neglected, role on the evolution of this biodiversity hotspot during the last glacial period. The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods.

A Small Mammal Community in a Forest Fragment, Vegetation Corridor and Coffee Matrix System in the Brazilian Atlantic Forest

The objective of our work was to verify the value of the vegetation corridor in the conservation of small mammals in fragmented tropical landscapes, using a model system in the southeastern Minas Gerais. We evaluated and compared the composition and structure of small mammals in a vegetation corridor, forest fragments and a coffee matrix. A total of 15 species were recorded, and the highest species richness was observed in the vegetation corridor (13 species), followed by the forest fragments (10) and the coffee matrix (6). The absolute abundance was similar between the vegetation corridor and fragments (F = 22.94; p = 0.064), and the greatest differences occurred between the vegetation corridor and the matrix (F = 22.94; p = 0.001) and the forest fragments and the matrix (F = 22.94; p = 0.007). Six species showed significant habitat preference possibly related to the sensitivity of the species to the forest disturbance. Marmosops incanus was the species most sensitive to disturbance; Akodon montensis, Cerradomys subflavus, Gracilinanus microtarsus and Rhipidomys sp. displayed little sensitivity to disturbance, with a high relative abundance in the vegetation corridor. Calomys sp. was the species least affected by habitat disturbance, displaying a high relative abundance in the coffee matrix. Although the vegetation corridors are narrow (4 m width), our results support the hypothesis in which they work as a forest extension, share most species with the forest fragment and support species richness and abundance closer to forest fragments than to the coffee matrix. Our work highlights the importance and cost-effectiveness of these corridors to biodiversity management in the fragmented Atlantic Forest landscapes and at the regional level.

Factors associated with the seroprevalence of leishmaniasis in dogs living around Atlantic Forest fragments.

Canine visceral leishmaniasis is an important zoonosis in Brazil. However, infection patterns are unknown in some scenarios such as rural settlements around Atlantic Forest fragments. Additionally, controversy remains over risk factors, and most identified patterns of infection in dogs have been found in urban areas. We conducted a cross-sectional epidemiological survey to assess the prevalence of leishmaniasis in dogs through three different serological tests, and interviews with owners to assess features of dogs and households around five Atlantic Forest remnants in southeastern Brazil. We used Generalized Linear Mixed Models and Chi-square tests to detect associations between prevalence and variables that might influence Leishmania infection, and a nearest neighbor dispersion analysis to assess clustering in the spatial distribution of seropositive dogs. Our findings showed an average prevalence of 20% (ranging from 10 to 32%) in dogs. Nearly 40% (ranging from 22 to 55%) of households had at least one seropositive dog. Some individual traits of dogs (height, sterilization, long fur, age class) were found to positively influence the prevalence, while some had negative influence (weight, body score, presence of ectoparasites). Environmental and management features (number of cats in the households, dogs with free-ranging behavior) also entered models as negative associations with seropositivity. Strong and consistent negative (protective) influences of the presence of chickens and pigs in dog seropositivity were detected. Spatial clustering of cases was detected in only one of the five study sites. The results showed that different risk factors than those found in urban areas may drive the prevalence of canine leishmaniasis in farm/forest interfaces, and that humans and wildlife risk infection in these areas. Domestic dog population limitation by gonadectomy, legal restriction of dog numbers per household and owner education are of the greatest importance for the control of visceral leishmaniasis in rural zones near forest fragments.

Distribution extension of Phaenomys ferrugineus (Thomas, 1894), and new data on Abrawayaomys ruschii Cunha and Cruz, 1979 and Rhagomys rufescens (Thomas, 1886), three rare species of rodents (Rodentia: Cricetidae) in Minas Gerais, Brazil

Herein we report for the first time the occurrence of Phaenomys ferrugineus in the state of Minas Gerais and present additional data on the geographical distribution of Abrawayaomys ruschii and Rhagomys rufescens in this state. These latter two species were reported from some localities in the Atlantic Forest of Brazil, but their presence in Minas Gerais state is restricted to few localities. These data reinforce the necessity of surveys over long periods of time and the use of pitfall traps in order to establish the real geographical distribution of small mammal species and to indicate priority areas for the conservation of this group of mammals.

Mammals of medium and large size in Santa Rita do Sapucaí, Minas Gerais, southeastern Brazil

The diversity of Brazilian vertebrates is regarded among the highest in the world. However, the biological diversity is still mostly unknown and a good part of it is seriously threatened by human activities. This study aimed to inventory the medium and large size mammals present in the Reserva Biologica de Santa Rita do Sapucai , an Atlantic forest reserve located in Santa Rita do Sapucai, southeastern Brazil. Sand-plots, photographic traps and searches for animal tracks on pre-existent trails in the area, were carried out once every two months between May 2006 and February 2007. The sand-plots and tracks were inspected during five consecutive days per sampling. We obtained 108 records of 15 species, mostly of carnivorans. Two confirmed species are threatened with extinction in Brazil ( Callithrix aurita and Leopardus pardalis ). The results suggest that the sampled reserve has high species richness and plays an important role in conservation of mammals in this landscape, including species threatened with extinction.

Abundance and richness of small mammals in fragmented Atlantic Forest of southeastern Brazil

Understanding the mechanisms that determine the abundance of small mammals in fragmented landscapes is crucial for the conservation of their populations. The abundance of marsupials and rodents was studied from 1999 to 2001 in fragments of Atlantic Forest. A capture–mark–recapture study was carried out in three small fragments (2.8–9.1 ha), two medium-sized fragments (158.9–197.6 ha) and three control areas within an 840-ha forest block. Twenty small mammal species were captured and the abundance was higher in small fragments than in either medium-sized or large ones. The marsupial Marmosops incanus and the rodent Euryoryzomys russatus were more abundant in small fragments; the marsupials Caluromys philander and Gracilinanus microtarsus showed a trend in the opposite direction. Our results suggest that several species are positively affected by increased productivity or by the habitat changes produced by edge effects in small fragments, including a sparser canopy and denser understorey vegetation.

Use of space by the black-eared opossum Didelphis aurita in a rural area in southeastern Brazil

No abstract available

Alien terrestrial mammals in Brazil: current status and management

The invasion of alien species is an important cause of biodiversity loss worldwide, and many mammals are considered successful invaders outside their former range, with recognized detrimental effects to native ecosystems. Our aim was to review the current literature on alien mammals that have established feral populations in Brazil and to systematize the existing knowledge. Furthermore, we evaluated the current distributions of all invasion mammals and discuss different management actions, including eradication techniques for island populations. We found 17 species of alien mammals living in the wild in Brazil. Based on the current literature and databases regarding invasive species, Lepus europaeus and Sus scrofa had the largest distributions in the Brazilian territory and seem to continue expanding their geographic distributions. Feral dogs and cats were the main alien predators threatening wildlife conservation, especially in protected areas. Further, we call attention to the invasion of Bubalus bubalis, a large species that currently thrives in isolated populations but seems to be quickly expanding its distribution. In conclusion, alien mammals are widespread in Southern and Southeastern Brazil, but at least four ungulate species (Indian sambar, horse, goat, and axis deer) still have small and isolated populations. Finally, future efforts need to evaluate the impacts of alien mammals in Brazil and techniques for their control.

Geographic distribution of the European hare (Lepus europaeus) in Brazil and new records of occurrence for the Cerrado and Atlantic Forest biomes

Abstract The introduction of alien species is among the main causes of biodiversity loss. There are many documented cases of introduced mammals having severe impacts on the ecosystem. The European hare (Lepus europaeus), native to Europe and Asia, was introduced to southern Brazil in the 1950s and has since expanded its geographic distribution considerably. In this study, we present a review of the known distribution of the European hare in Brazil, add new records of occurrence that expand the species distribution into southeastern Brazil and estimate the species dispersal rate in Brazil. We compiled at total of 135 distinct localities of occurrence for the species in Brazil, including published records and the previously unknown localities presented here. These records indicate a dispersal rate of 45.35 km/year for the introduced species. Of these known localities, 15 are in protected areas. Because of its high potential for even greater geographic dispersal and potential impacts on native species through competition and disease transmission, we recommend further research to better assess the species status and the implementation of public policies and management controls, especially in protected areas.

Local vs landscape drivers of primate occupancy in a Brazilian fragmented region

Understanding the drivers of species distributions in human-dominated landscapes is crucial for proposing sound conservation strategies. Primates are the most studied terrestrial vertebrate taxa, yet still, their response to forest loss and fragmentation widely varies among species. In this paper, we assessed the relative influence of local vs landscape features on occupancy of two primate species—the black-fronted titi monkey and the black-pencilled marmoset, in a Brazilian fragmented region. We created detection histories by performing repeated auditory surveys on 25 native vegetation patches. Then, we fitted occupancy models using habitat and GIS-based data as site covariates and weather conditions as detection covariates. We found that forest-like canopy elements are important for the titi monkey, a canopy-dependent species. Occupancy of marmoset, an opportunistic species, was also related to local elements, but in a lesser extent. In addition, we found that ignoring detectability in playback call surveys created a 20 % difference in occupancy estimates for the marmoset. We conclude that drivers of primate occupancy at the studied landscape rely mainly on local key habitat elements, so that on-ground conservation actions should not focus on habitat amount alone. Furthermore, we reiterate that primate researchers should explicitly account for imperfect detection to avoid substantial detectability bias.