Abundance, habitat use and diet of Callicebus nigrifrons Spix (Primates, Pitheciidae) in Cantareira State Park, São Paulo, Brazil

Entre abril de 2005 e maio de 2006, através de censos seguindo os pressupostos da metodologia de transecção linear, foram estimadas a densidade populacional e abundância de Callicebus nigrifrons Spix, 1823 (Pitheciidae) no Parque Estadual da Cantareira, Estado de São Paulo, Sudeste do Brasil (23°23'42S, 46°35'27W). Com um esforço amostral de 275,8 km de censos, os sauás foram a segunda espécie de primata mais abundante, apresentando um índice de abundância de 1,4 grupos para cada 10 km percorridos e uma estimativa de densidade de 12,21 ind./km² (variando de 8,45 a 17,63 ind./km²). A coleta de dados auxiliares durante os censos possibilitou a verificação da dieta e uso do hábitat pelos grupos de Callicebus, e os resultados evidenciaram uma relativa adaptabilidade à ambientes perturbados.

Species richness of pteridophytes in a montane Atlantic rain forest plot of Southern Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Analysis of floristic composition and structure as an aid to monitoring protected areas of dense rain forest in southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Spatial patterns or trees in the Picinguara coastal sandy forest (state of Sao-Paulo, Brazil)

The species of the sandy plains forests (forests of the ''restingas'') have not yet had their spatial patterns studied as aids to the understanding of the diversity found in the different physiognomies along the Brazilian coast. In this paper a 10 x 10 m quadrat framework laid in a hectare of a tree dominant forest in the sandy plains of the Picinguaba area of the Serra do Mar State Park (municipality of Ubatuba, state of São Paulo, Brazil) was used to assess the spatial pattern of distribution for the ten most important species : Pera glabrata, Euterpe edulis, Eugenia brasiliensis, Alchornea triplinervea, Guatteria australis, Myrcia racemosa, Jacaranda semiserrata, Guarea macrophylla, Euplassa cantareirae and Nectandra oppositifolia. The spatial patterns were inferred through the calculations of their T-Square Index (C) and Dispersal Distance Index (I). P. glabrata shows a random pattern, E. edulis aggregate, E. brasiliensis, A. triplinervia, G. australis, E. cantareirae and N. oppositifolia with a tendency between aggregate and uniform and, M. racemosa, J. semiserrata and G. macrophylla between aggregate and random. Although the indexes are dependent of the sample size and of the technique adjustments, the relationship of the pattern with the environmental factors is shown by clustering methods. The results give confirmation of how the spatial patterns bring associations between populations and shape of the vegetation physiognomy.

Jaguar (Panthera onca) food habits in Atlantic rain forest of southeastern Brazil

Between January and December 1996, the food habits of a relict population of jaguars were studied in 220 km(2) Linhares Forest Preserve, which comprises much of the remaining old-growth Atlantic Forest of Espirito Santo, Brazil. Fecal analysis indicated opportunistic feeding on 24 prey species (N = 101 scats). Mammals represented 87 percent of the total items, followed by reptiles (9.8%) and birds (2.8%). Considering prey weight, 23.4 percent of the items weighed 1-3 kg, 40.5 percent were 3-10 kg, and 27.7 percent weighed more than 10 kg. Analysis of relative prey frequency and biomass indicated that the diet was concentrated in two prey types: long-nosed armadillo and white-lipped peccary. Literature data suggest that forest jaguars rely on the same mammal prey over their entire geographic range.

Bird species of black water inundation forests in the Jau National Park (Amazonas state, Brazil): their contribution to regional species richness

We compared the relative contribution of blackwater inundation forest (igapo) and unflooded (terra firme) forest for regional bird species diversity in the lower Rio Negro region. For analyses of habitat preference we used mist-net samples and an unpublished bird species check-list. The igapo forest had lower bird species diversity than the terra firme forest. However, some 14% of the forest bird species in the region are restricted to igapo forest. Species composition was found to be distinct between the understories of the two forest types. Common forest bird guilds in the Neotropics such as ant-following birds avoid igapo forest. The differential habitat selection among birds in the inundated and unflooded forest is likely to result from vegetation structure and biological interactions such as aggressive behaviour. Since the inundated forest has a typical biota, conservation efforts needs to be directed to protect these habitats. Unfortunately, inundation forests are threatened by several human actions, especially dam construction. The extent of protected areas in the Brazilian Amazon is insufficient for the adequate protection of the inundated habitats, because it includes only 3% of the total area.

Phytosociological studies in the morro do diabo forest (Pontal do Paranapanema, SP), Brazil

Results are given of a phytosociological study of a forest located in the Morro do Diabo State Park. in the county of Teodoro Sampaio (22 degrees 31'S, 52 degrees 10'W), Pontal do Paranapanema region, state of São Paulo. The point-centered quarter method, using 300 sampling points, was used establishing 3 trails of 100 sampling points each, 10 m interdistant. All woody vegetation with a breast height diameter of 5 cm or more were samplied. Three distinct ecotopes could be identified in the forest: the lower, thc slope and the peak, which were analised separately.The families that presented the greatest numbers of genera, species and individuals were Leguminosae, Euphorbiaceae and Myrtaceae, followed by Rutaceae, Lauraceae, Meliaceae and Moracea. A total of 104 species, 85 genera and 37 families were sampled by the phytosociological survey. The relative sociological position of each plant family or species varied according to ecotope.

Density and population size of mammals introduced on a land-bridge island in southeastern Brazil

The introduction of alien species is one of the main threats to the conservation of native species, especially in island ecosystems. Here, we report on the population growth of 15 species of mammals introduced in 1983 on the island of Anchieta, an 828 ha land-bridge island in southeastern Brazil. We estimated the density of mammals through 296 km of line transect census. Five species introduced became extinct (coypu, brocket deer, six-banded armadillo, nine-banded armadillo, maned three-toed sloth); six became over-abundant (marmoset, coati, agouti, seven-banded armadillo, and capybara); one has a stable population (capuchin monkey). Anchieta Island has the highest density of mammals in the entire Atlantic forest (486.77 ind/km(2)), especially nest predators (232.83 ind/km(2)) and herbivores (253.58 ind/km(2)). Agoutis (Dasyprocta spp.) and marmosets (Callithrix penicillata) were, by far, the species with the highest population growth. The high density of mammals in this island may have strong consequences for plant recruitment and bird diversity.

Nests and nesting sites of Brazilian forest rodents (Nectomys squamipes and Oryzomys intermedius) as revealed by a spool-and-line device

Patterns of nest construction and nest site selection of two murid rodents of the Brazilian Atlantic rainforest were described. The animals were captured in an area of about 1.5 ha of primary forest, marked, equipped with a spool-and-line device and released at the capture point. The next day we followed the thread to find their nests. In total 11 nests of Nectomys squamipes (Brants, 1827) and 13 of Oryzomys intermedius (Leche, 1886) were found. They were all egg-shaped, about 15 cm long and 10 cm wide, without any apparent entrance and consisted of dry leaves and grass. The two species differed in the selection of nest sites. The nests of N. squamipes were close to streams and built inside decomposed fallen logs or using natural entrances between the soil and tangled roots or rocky crevices. Nests of O. intermedius were built under or inside fallen logs and inside aerial root systems of palms. The spool-and-line technique used here is useful to provide detailed information on several aspects of the ecology and natural history of small mammals.

Habitat patch size modulates terrestrial mammal activity patterns in Amazonian forest fragments

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Distribution and abundance of four caiman species (Crocodylia: Alligatoridae) in Jaú National Park, Amazonas, Brazil

Jaú National Park is a large rain forest reserve that contains small populations of four caiman species. We sampled crocodilian populations during 30 surveys over a period of four years in five study areas. We found the mean abundance of caiman species to be very low (1.0 ± 0.5 caiman/km of shoreline), independent of habitat type (river, stream or lake) and season. While abundance was almost equal, the species' composition varied in different waterbody and study areas. We analysed the structure similarity of this assemblage. Lake and river habitats were the most similar habitats, and inhabited by at least two species, mainly Caiman crocodilus and Melanosuchus niger. However, those species can also inhabit streams. Streams were the most dissimilar habitats studied and also had two other species: Paleosuchus trigonalus and P. palpebrosus. The structure of these assemblage does not suggest a pattern of species associated and separated by habitat. Trends in species relationships had a negative correlation with species of similar size, C. crocodilus and P. trigonatus, and an apparent complete exclusion of M. niger and P. trigonatus. Microhabitat analysis suggests a slender habitat partitioning: P. trigonatus was absent from river and lake lgapo (flooded forest), but frequent in stream Igapó. This species was the most terrestrial and found in microhabitats similar to C crocodilus (shallow waters, slow current). Melanosuchus niger inhabits deep, fast moving waters in different study areas Despite inhabiting the same waterbodies in many surveys, M. niger and C. crocodilus did not share the same microhabitats. Paleosuchus palpebrosus was observed only in running waters and never in stagnant lake habitats. Cluster analysis revealed three survey groups: two constitute a mosaic in floodplains. (a) a cluster with both M. niger and C crocodilus, and another (b) with only C. crocodilus. A third cluster (c) included more species, and the presence of Paleosuchus species. There was no significant difference among wariness of caimans between disturbed and undisturbed localities. However, there was a clear trend to increase wariness during the course of consecutive surveys at four localities, suggesting that we, more than local inhabitants, had disturbed caimans. The factors that are limiting caiman populations can be independent of human exploitation. Currently in Amazonia, increased the pressure of hunting, habitat loss and habitat alteration, and there is no evidence of widespread recovery of caiman populations. In large reserves as Jaú without many disturbance, most caiman populations can be low density, suggesting that in blackwater environments their recovery from exploitation should be very slow.

Diversity of the ichthyofauna in the Serra do Mar State Park- Núcleo Santa Virgínia, Sáo Paulo State, Brazil

The aim of this work was to assess and compare the diversity of the ichthyofauna in three headwater rivers of Paraíba-do-Sul basin in the Serra do Mar State Park, Núcleo Santa Virgínia. A total of 1,774 specimens of 16 species of fishes belonging to 6 families were caught. Characiforms were the most abundant fish at all three sites, followed by Cyprinodontiformes, Siluriformes, and Perciformes. The Shannon index (H′), evenness (E), and the Jaccard and Morisita-Horn similarity indexes were low, indicating both low diversity and low similarity of species among the three streams. The values of these indexes should be evaluated according to the biotic and abiotic conditions in each environment. It is clear that in mountain streams of the Atlantic Forest, these low values occur because of the presence of a few abundant and many rare species.

No changes in seedling recruitment when terrestrial mammals are excluded in a partially defaunated Atlantic rainforest

One of the most intriguing questions in ecology is how to identify which and how many species will be able to inhabit human-modified landscapes. Large-bodied mammals structure plant communities by trampling, herbivory, seed dispersal and predation, and their local extinction may have pervasive consequences in plant communities due to the breakdown of key interactions. Although much attention has been given to understanding the effects of defaunation on plant communities, information on the potential impacts on plant functional groups (seed dispersal, seed size and seedling leaves defense) inhabiting continuous forests after defaunation is scarce. We conducted mammal surveys (line transects and camera trapping) to determine the defaunation status of a continuous Atlantic forest in Brazil. Then, we evaluated the effects of defaunation on seedling diversity, richness and abundance of functional groups using 15 plot-pairs (each pair with one open and one exclusion plot) monitored over 36. months. We found that the studied area is partially defaunated because it exhibits high abundance of primates, while terrestrial mammals, such as large rodents and ungulates, are rare. We found no significant changes in either seedling richness and diversity or in the seedling composition of plant functional groups in response to mammal exclosure. Seedling mortality and recruitment were similar between plot types. Our findings suggest that at semi-defaunated areas, where arboreal species are still present, terrestrial mammals have low impacts on the plant community reassembly. © 2013 Elsevier Ltd.

Diversidade genética e estrutura populacional da anta (Tapirus terrestris) na Serra do Mar, São Paulo, Brasil

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

Defaunação e efeitos-cascata sobre a diversidade vegetal em uma ilha semi-defaunada na Floresta Atlântica

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC