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The “capuchinos” form a monophyletic group within the Neotropical seedeaters of the genus Sporophila and are typically smaller than the other congeners. Many of the 12 species of this group are endangered, but reproductive information is scarce for most of them. Here we present the descriptions of nests, eggs, nestlings, and nesting habitats for the Pearly-bellied Seedeater (Sporophila pileata). From 2012 to 2017 we found 83 nests constructed in herbaceous plants present in open marshlands, 15–73 cm above water or humid ground. Nests were deep cups built of grass stems, inflorescences, and rootlets, attached with spider web. Nests measured 59.3 ± 4.7 mm outside diameter, 50.7 ± 6.5 mm outside height, 41.6 ± 3.2 mm internal diameter, and 35.7 ± 3.3 mm internal depth. Eggs were oval with white, grayish, or greenish background color with black and brown spots mainly in the obtuse pole. They weighed 1.2 ± 0.1 g and measured 16.3 ± 0.8 per 12.2 ± 0.3 mm. Clutches consisted of 1–3 eggs. Our study sites...

The degree of habitat specificity determines the distinctive ways that birds respond to land-use and climate change. Information on habitat-use, movement potential and sensitivity to human disturbance can promote reliable predictions on species response to spatial and temporal global changes. Here, we made an extensive review about habitat-use of 52 birds with distribution mainly in the Cerrado domain, a world hotspot with alarming climate change and land-use projections. We described habitat-use, classified habitats into three categories (grasslands, savannahs, and forests), inferred movement potential and sensitivity to human disturbance from records in anthropogenic matrices and identified knowledge gaps. More than one-half of the species surveyed predominantly use only one major natural habitat category, mostly forests, or are highly associated to microhabitats or to specific habitat features (62%, n = 32). Grasslands were the most used habitat (n = 32). Most species apparently will encounter difficulties to move through the landscape (27% and 36% of the species have low and medium movement potential, respectively) and are highly sensitive to human disturbance (48%). Furthermore, a considerable low number of species was frequently recorded in non-natural habitats and considered of low sensitivity (n = 6). Our results offer a wide understanding of relevant habitats and microhabitats for Cerrado birds and can add more reality to future model estimates, enhancing success of current and future conservation initiatives.

Os metodos de observacao direta do comportamento animal podem ser classificados em metodos de unico ponto ou sequencial. Aqui discutimos as vantagens e desvantagens da utilizacao desses metodos em estudos sobre o comportamento de forrageamento das aves e sugerimos ferramentas estatisticas apropriadas para a analise de dadosdependentes, como aqueles oriundos de observacoes sequenciais. O metodo de unico ponto e apropriado para estudos com aves que sejam facilmente encontradas em campo e possui o beneficio de evitar a dependencia entre as amostras. O metodo de observacoes sequenciais e recomendado para estudos feitos com especies raras, dificeis de serem visualizadas entre a vegetacao ou quando taxas e transicoes de comportamentos sao importantes para a pesquisa, alem de possibilitar amostras comportamentais mais completas. Entretanto, a escolha de observacoes sequenciais implica em problemas com a dependencia entre os registros, pois estes possuem erros correlacionados que promovem uma estimativa subestimada da variância da amostra. Ferramentas estatisticas que permitam ajustes para autocorrelacao entre as amostras devem ser utilizadas nestes casos. As cadeias de Markov sao apropriadas para estudos sobre transicoes de comportamentos e reconhecem a interdependencia entre as amostras sequenciais. A Analise de Variância para medidas repetidas e a Analise de Variância Multivariada podem ser utilizadas nas analises de dados dependentes, mas e preciso ter atencao aos pressupostos dos testes. Os modelos lineares generalizados mistos contribuem com as analises de registros sequenciais (dependentes) por modelar a parte aleatoria com a inclusao de uma matriz de variâncias-covariâncias. A escolha do metodo de observacao direta deve ser feita com consideracoes sobre o contexto que envolve a pesquisa e atencao deve ser dada aos pressupostos das ferramentas estatisticas que serao aplicadas. ABSTRACT - METHODS OF DIRECT OBSERVATION IN STUDIES ON FORAGING BEHAVIOR OF BIRDS The methods of direct observation of animal behavior can be classified into single-point or sequential methods. We intend to discuss the advantages and disadvantages of using each of these methods in studies on the foraging behavior of birds and to suggest appropriate statistical tools for the analysis of dependent data, such as those derived from sequential observations. Single-point methods are appropriate for studies with birds that are easily found in the field and have the benefit of avoiding dependence between samples. The sequential observation are suitable for surveys of rare species and those difficult to see among vegetation or when rates and transitions are important for research, in addition to enabling more complete behavioral samples. However, the selection of sequential observations denotes problems related to the dependency between records, since these have correlated errors that promote an underestimated value of the sample variance. Statistical tools that allow statistical adjustment for auto-correlation should be used in these cases. Markov chains are appropriate for behavioral transitions studies and recognize the interdependence between sequential samples. Repeated-measure Analysis of Variance and Multivariate Analysis of Variance can be used for dependent data analyzes, but attention must be paid to the assumptions of the tests. The generalized linear mixed models can contribute to the analysis of continuous records by modeling the random part including a variance-covariance matrix. The choice of the method of direct observation should be madewith considerations about the context that involves the research and attention must be given to the assumptions of the statistical tools that will be applied.

Complex frugivory networks are common in heterogeneous environments, but how the structure of those networks varies due to seasonality and other environmental factors remains unclear. For example, seasonal variation in rainfall can influence fruit production and diaspore characteristics, which could alter the quantity and quality of resources available to different animals in the network and, hence, network structure. We investigated how a frugivory network varied seasonally in Brazilian savanna (Cerrado), where there are well-defined dry and wet seasons and fructification mainly during the rainy season for most tree species. We recorded fruit consumption by animals during the dry and wet seasons in two different gallery forests and used these data to test the hypotheses that connectance, links per species and nestedness would be higher in the dry season than rainy season due to low available food in the former that would be consumed by various species of frugivores. Concomitantly, we also measured seed width and lipid content from diaspores of the fruiting trees to determine if these characteristics influenced interaction properties between fruiting trees and frugivores. Among the measured network parameters, connectance, links per species and specialization varied between seasons in one site but not in the other, indicating that seasonal variation in networks is not necessarily consistent over time or space. The number of tree species with small diaspores with high lipid content differed between seasons, and those characteristics were key factors increasing the interaction parameter of fruiting trees. We suggest that network stability between seasons may be related to local frugivore diversity, resource availability, and fruit quality.

In this chapter, we have compiled the literature for the 23 Brazilian owl species, which represent almost one-third of all Neotropical owls. Our main objective here was to review the taxonomy, distribution, ecology, and conservation of each species, both revealing gaps in our knowledge and supplying directions to promote more research on Brazilian owls. Even though in the last 15 years there was an impressive increasing number of specific publications on owls in Brazil, particularly on food habits, we have detected that other essential data about distribution, taxonomy, population density, habitat requirements, reproductive biology, and anthropogenic effect on owl populations are needed for most owl species. Probably the lack of basic biological information on most species is responsible for the relative absence of owls in the Brazilian official lists of threatened fauna in regional and national scales.

Although most raptor species are found mainly in the tropics, information on their home range and spatial requirements in the Neotropics is still scarce. In this study, we used radio telemetry to evaluate the home range and the habitat use and selection of five Roadside hawks, Rupornis magnirostris (Gmelin, 1788) in a heterogeneous landscape in southeastern Brazil. The average home range size calculated using the adaptive kernel method (95% isopleth) was 126.1 ha (47.4–266.7 ha), but using the minimum convex polygon method (95% isopleth) it was 143.54 ha (32.6–382.3 ha). The roadside hawk explored a wide variety of habitats, most of them opportunistically, as suggested in the literature. Despite this, habitat quality could influence home range size and promote habitat selection. The observation of habitat use as expected, as well as the relatively small home range size, could be related to the generalist/opportunistic behaviour of the roadside hawk.

Sixteen opportunistic field observations of eight species of Brazilian raptors (Falconiformes and Strigiformes) are reported here as a contribution to the knowledge of the natural history of these poorly studied birds in Brazil. The observations are related to the food habits (Buteo albicaudatus, Herpetotheres cachinnans, Milvago chimachima, Falco femoralis), reproduction (Asio stygius, Megascops choliba), mobbing behaviour elicited in other birds (Geranospiza caerulescens, H. cachinnans, F. femoralis, A. stygius, Athene cunicularia) and a rare case of leucism in owls (A. cunicularia).

The Collared Crescentchest (Melanopareia torquata) is endemic to the Cerrado Biome, and distributed mainly in Brazil, but extending to Bolivia and Paraguay. Although considered of least concern globally, it is threatened in the state of Sao Paulo in south-eastern Brazil. In this study we examined the morphology and some aspects of behaviour of the Collared Crescentchest. Birds were captured with mist-nets using playback in September–December 2006 and October–November 2007. For each captured bird, we took a range of morphological measurements, looked for brood-patches and moult, and took a blood sample for genetic determination of sex. Of the 35 individuals captured, only five were female, probably as a result of behavioural differences between sexes, with males apparently responding more readily to the playback. Furthermore, birds with white dorsal patches exhibited more aggression or risk taking behaviour than birds without patches. However, there was no sexual dimorphism in any of the morphological or colour traits measured (although the female sample was small). Brood-patches were present mainly in October and November, but we did not detect any cloacal protuberance. Among the four species that comprise the family Melanopareiidae, this is the first record of brood-patches in males.

Sampling owls in a reliable and standardized way is not easy given their nocturnal habits. Playback is a widely employed technique to survey owls. We assessed the influence of wind speed, temperature, air humidity, and moon phase on the response rate of the Tropical Screech Owl Megascops choliba and the Burrowing Owl Athene cunicularia in southeast Brazil. Tropical Screech Owl occurs in scrubland and wooded habitats, whereas the Burrowing Owl inhabits open grasslands to grassland savannah. Sixteen survey points were systematically distributed in four different landscape types, ranging from open grassland to woodland savannah. Field work was conducted in 2004 from June to December, the reproductive season of the two owl species. Our study design consisted of eight field expeditions of five nights each; four expeditions occurred under full moon and four under new moon conditions. At each survey station, we performed a broadcast/listening sequence involving several calls and vocalizations from each species, starting with Tropical Screech Owl (the smaller species). From 112 sample periods for each species within their respective preferred habitats, we obtained 54 responses from Tropical Screech Owl (48% response rate) and 30 responses (27% response rate) from Burrowing Owl. We found that the response rate of Tropical Screech Owl increased under conditions of higher temperature and air humidity, while the response rate of Burrowing Owl was higher during full moon nights.

The feeding habits of the maned wolf were studied in southeast Brazil to understand its response towards changes in the environment and in relation to its prey. By occurrence, miscellaneous fruits, small mammals and wolf's fruit were the most consumed items. Armadillos, small mammals and wolf's fruit (Solanum lycocarpum) provided most of the ingested biomass. While wolf's fruit and small mammals were mainly consumed in the dry season, other miscellaneous fruits were taken mostly in the wet season. There was selectivity in the predation on some small mammal species. The maned wolf's diet followed patterns similar to those found in more pristine areas. O habito alimentar do lobo guara foi estudado no sudeste do Brasil para descrever suas respostas as alteracoes do ambiente e em relacao as suas presas. Por frequencia de ocorrencia, as frutas silvestres, os pequenos mamiferos e a fruta-do-lobo foram os itens mais consumidos. Tatus, pequenos mamiferos e a frutas-do-lobo (Solanum lycocarpum) constituiram os ite...

A variety of factors influence prey selection by predators. Because Barn Owls (Tyto alba) and Burrowing Owls (Athene cunicularia) differ in size and foraging tactics, we expected differential predation on small mammal prey. We hypothesized that the Barn Owl, an active predator, would prey on smaller and younger individuals than the Burrowing Owl, a sit-and-wait predator. We used pellet analyses to evaluate selection of small mammals by the two owls in relation to prey species, age, and size at the Ecological Station of Itirapina, state of Sao Paulo, in southeastern Brazil. Small mammals constituted most of the prey individuals and biomass in the diet of Barn Owls. Although Burrowing Owls consumed a wider range of taxa, small mammals represented one-third of all biomass consumed. With respect to small mammals, Barn Owls foraged selectively relative to prey species, size, and age. Burrowing Owls foraged opportunistically relative to prey species, but selectively relative to prey size and age. Barn Owls selected smaller and younger (juvenile and subadult) individuals of the delicate vesper mouse (Calomys tener) and Burrowing Owls preyed more on larger and older (subadult only) individuals. Morphology and behavior of both prey and predators may explain this differential predation. Our data suggest that the active predator feeds on smaller and younger prey and the sit-and-wait predator took relatively larger and older prey.

O cerrado é um dos biomas mais ameaçados no mundo, apresentando algumas das maiores taxas de destruição causadas principalmente pela agropecuária. Poucos estudos têm avaliado a diversidade local de aves no cerrado, especialmente em áreas marginais desse bioma. A Estação Ecológica de Itirapina (EEI) contém um dos últimos remanescentes de campos naturais e cerrados do estado de São Paulo. Um levantamento das aves desta unidade de conservação, feito tanto por observações casuais como sistemáticas entre 1998 e 2007, e complementado por revisão de literatura, revelou que 231 espécies apresentaram ocorrência recente na área. Desse total, 38 espécies (16,4%) encontram-se na lista de espécies ameaçadas para o estado de São Paulo e/ou são endêmicas do Cerrado, um alto número quando comparado com outras áreas de cerrados paulistas ou mesmo em relação ao Brasil Central. Tal fato reforça a importância da EEI em relação à conservação da avifauna e demonstra que a mesma está mantendo sua função de conservar a biodiversidade. Adicionalmente, ao longo dos 10 anos de estudo foram detectadas várias ameaças à EEI, e neste sentido são recomendadas aqui algumas sugestões de manejo que consideramos essenciais para essa unidade de conservação manter ou mesmo aumentar sua diversidade de aves. Currently the Cerrado biome is one of the most threatened in the world because high taxes of destruction, mostly by agriculture and cattle. Few assessments of local bird diversity have been made in this biome, particularly in non core areas. The Estação Ecológica de Itirapina (EEI) maintains one of the last natural grassland savannah remnants of state of São Paulo, south-east Brazil. We conducted casual and systematic observations of birds in this reserve between 1998 and 2007, which altogether with additional literature revision yielded 231 species with recent occurrence. We report 38 species (16.4%) threatened with extinction in São Paulo and/or endemic to the Cerrado Region, an impressive result in comparison to other cerrado areas in São Paulo and even in Central Brazil. These results reinforce the importance of EEI for bird conservation and mean EEI is maintaining its function as a conservation unity. However, as a result of several menaces observed to this reserve during our ten years study, we suggest some management practices for the maintenance or even increasing of bird diversity in this reserve.

The feeding ecology of the White-tailed Hawk (Buteo albicaudatus albicaudatus) was studied in south-eastern Brazil. The aims of this study were to: (1) quantify the diet of the White-tailed Hawk, including the number of prey species eaten and their biomass; (2) investigate the influence of season on diet; and (3) describe the breadth of the diet. Pellets found beneath seven White-tailed Hawk nests and several roosting sites around the nesting sites were collected from September 2000 to September 2001. The analysis of 259 pellets revealed 31 prey species or morphospecies, 3296 individuals and 7.2 kg of estimated consumed biomass. Five insect orders (Hymenoptera, Heteroptera, Odonata, Isoptera and Lepidoptera) and one vertebrate order (Chiroptera) were reported as prey for the first time for this species. By number, invertebrates made up 88% of all prey items, 63% of which belonged to a single orthopteran family (Acrididae). Among vertebrates, rodents were the group most consumed by number and represented 73% of all vertebrate prey items. However, in terms of estimated biomass consumed, the most represented groups were rodents (50%), orthopterans (21%), birds (11%) and lizards (7%). Vertebrates alone yielded 77% of the total biomass consumed. Whereas the White-tailed Hawk may be classified as insectivorous by number of prey, it is carnivorous with respect to biomass ingestion. According to the Levin’s diet-breadth index, this raptor could be considered to be a specialist predator of grasshoppers (Acrididae) by prey number and of rodents by prey biomass. Food eaten was dependent on season, with more mammals taken during the dry (breeding) season and a broader range of prey during the wet season.

We analyzed diet and prey selection of the relatively unknown albicaudatus subspecies of the White-tailed Hawk (Buteo albicaudatus). Our study was based on an analysis of 259 pellets collected from September 2000 to September 2001 in the municipality of Juiz de Fora in southeastern Brazil. We also assessed the abundance of small mammals with pitfall traps (2,160 trap-nights). Small mammals composed 52.5% of the estimated biomass consumed by the hawks, and selection appeared to be mediated by abundance. The Bonferroni confidence intervals procedure revealed that when abundance of small mammals was higher, the hawks were selective, preying on Calomys tener more than would be expected by chance (P < 0.05); other rodents were consumed less than expected. Oligoryzomys nigripes, Oxymycterus sp., and Gracilinanus spp. were taken in the same proportion as they were found in the field. During reduced prey abundance (October–March), White-tailed Hawks preyed opportunistically on small mammals. Differences ...

The study focused on vulnerability of small savannah mammals in relation to hearing, locomotion and activity on full moon nights in a continuum from more bushy to more open Cerrado physiognomies in order to understand predator selection in a southeast Brazilian savannah preserve. Diet preference of three nocturnal/crepuscular predators, a canid (maned wolf – Chrysocyon brachyurus) and two raptors (barn owl – Tyto alba and burrowing owl – Athene cunicularia), were assessed, simultaneously to measurement of rodent tympanic bulla volume, calculation of a prey bipedalism index (ratio between length of fore and hind limbs) and small mammal sampling in three different Cerrado physiognomies and on different moon phases. High bulla volume, low bipedalism index (bipedal locomotion) and high abundance/activity on darker nights and in bushy habitats are assumed as less vulnerability to predation. Although the Echymyidae Clyomys bishopi was the least vulnerable prey to aerial attack, possibly due to its good hearing (highest bulla volume), its predominantly quadrupedal locomotion (high bidepalism index) seemed not to be so efficient against the maned wolf, as it was preyed upon more than expected by chance by this canid. The Cricetidae Olygoryzomys nigripes and Calomys tener were either consumed opportunistically by the two owls or they were preyed upon at a frequency lower than expected by chance by the maned wolf. However, as the dominant species in the study area, C. tener was always consumed in large proportions. Olygoryzomys nigripes was the least vulnerable prey to the analysed predators, possibly due to its efficient locomotion (low bipedalism index) and scansorial habits, even though its bulla volume suggests a low hearing capability and the level of activity is the same during both lunar phases. As a vulnerable prey relative to hearing, locomotion and predominantly terrestrial habits, Calomys tener's strategy against predators is to decrease its activity on nights with a full moon and to inhabit physiognomies with more dense vegetation cover. The Cricetidae Necromys lasiurus seems to be especially vulnerable to the barn owl as it was consumed more than expected by chance. Its bulla relative volume was low, the bipedalism index and short tail indicate poor locomotion efficiency, and body size as well as terrestrial habits suit the barn owl's size and aerial hunting strategy. Mechanisms such as inflated bullae seem to play a secondary role in a more wooded environment, such as the savannah; locomotion mode, use of refuges and the exhibition of a more secretive behaviour (such as avoidance of moonlight) seem more effective in these neotropical landscapes.

The Tropical Screech-Owl (Megascops choliba) is a small nocturnal raptor that uses a large range of habitats throughout Brazil. Although it is one of the most abundant owls in the Neotropics, nothing has been published on its spatial ecology, and information on basic natural history is scarce. We followed four radio-tagged males to estimate home-range size and habitat selection in a savanna (cerrado) patch in southeastern Brazil. The mean (±SD) home-range size was 51.2 (26.9) ha using the 95% minimum convex polygon (MCP) method and 80.8 (40.2) ha using the 95% fixed kernel (FK) method. The mean (±SD) core area was 22.4 (8.8) ha (65% FK). During nocturnal activities, owls preferred semi-open (campo cerrado) and semi-closed (cerrado sensu stricto) habitats and avoided open habitats (campo sujo). Gallery forests and patches of invasive pines were preferred for roosting during the day. The variation in size of individual home ranges may be explained by individual's breeding status and habitat structu...

Analysis of 105 scats of the maned wolf (Chrysocyon brachyurus) collected in central Brazil yielded 304 occurrences of food items of which fruits of Solanum lycocarpum, rodents, and birds accounted for 61.5%. By analysis of minimum number of individual animals, rodents and birds were 75% of a total of 156 prey. On the other hand, fruits of S. lycocarpum and armadillos (Dasypus spp.) were the bulk of the total estimated biomass consumption, yielding 63.7% in a total of 73.5 kg. Rodents were mostly captured during the dry season, while miscellaneous fruits were consumed mostly in the wet season. The consumption of S. lycocarpum fruits and armadillos was aseasonal. Small rodents were taken in about the ranks of abundance in the study area, but S. lycocarpum fruits were actively searched by maned wolves, for its occurrence is limited to secondary savanna. Prey and fruits typical of savanna (‘cerrado’) and grassland (‘campo’) were the bulk of species, occurrences, prey numbers, and biomass consumed. These findings reinforce the importance of conservation of cerrado and campo in central Brazil. Despite maned wolf being a vulnerable species, its feeding habits are opportunistic, and the main reasons for its decline are likely to be habitat destruction and human disturbance.

Analysis of 400 scats of the maned wolfChrysocyon brachyurus (Illiger, 1815), collected in Serra da Canastra National Park from November 1998 to January 2000 yielded 1688 occurrences of 69 identified food items, 49.5% of which were represented by plant items and 50.5% by animal items. According to the frequency of occurrence analysis, the most important food item categories were wolf’s fruit,Parinari obtusifolia (Chrysobalanaceae), small mammals and birds. When the estimated biomass consumption is considered, the animal items became more important (56.8%) than plant items (43.2%). Small mammals were consumed more in the dry season, while miscellaneous fruits and arthropods were consumed mostly in the wet season. Functional response was found only for the category miscellaneous fruits; however, seasonality analysis revealed that wolf’s fruit and small mammals were consumed according to their availability in the area. Prey selection was observed for most of the small mammal species, emphasizing a high level of consumption ofNecromys lasiurus, Monodelphis sp. andGracilinanus sp. The finding that most of the diet was composed of fruits and animal items from open areas of the savannah-like Cerrado led us to suggest that the maned wolf spends most of its time preying in this habitat, indicating a need to establish conservation policies for the Cerrado.

I observed, and documented in detail, Ferruginous Pygmy Owl (Glaucidium brasilianum) predation on a mobbing Fork-tailed Flycatcher (Tyrannus savanna) in south-east Brazil. Events described in this account are supported with original photos. In addition to the predation event, I list 12 mobbing bird species that were alarmed by the presence of this raptor in the study area, including Trochilidae (Eupetomena macroura), Formicariidae (Formicivora rufa), Tyrannidae (Camptostoma obsoletum, Elaenia cristata, E. flavogaster, E. chiriquensis, T. savana, Myiarchus tyrannulus), Turdidae (Turdus leucomelas, T. amaurochalinus, T. rufiventris) and Emberizidae (Coryphospingus cucullatus). The Fork-tailed Flycatcher may represent 35-76.8% of the pygmy-owl body mass (41-80 g), which supports early reports about the predation on relatively large prey by this owl species. Although most authors have suggested that mobbing birds are subject to a low predation risk, this report and others confirmed that these events are not negligible and can be deadly dangerous to the mobbers, and conversely profitable to the raptor. Um evento de predação da tesoura Tyrannus savana (Aves: Tyrannidae) que apresentava comportamento de tumulto frente ao Caburé Glaucidium brasilianum (Aves: Strigidae) no sudeste brasileiro é descrito em detalhe. São incluídas fotografias do evento e uma lista de 12 espécies de aves que exibiram este comportamento frente ao caburé, abrangendo Trochilidae (Eupetomena macroura), Formicariidae (Formicivora rufa), Tyrannidae (Camptostoma obsoletum, Elaenia cristata, E. flavogaster, E. chiriquensis, T. savana, Myiarchus tyrannulus), Turdidae (Turdus leucomelas, T. amaurochalinus, T. rufiventris) and Emberizidae (Coryphospingus cucullatus). A ave predada pode representar uma grande parte (35-76,8%) da massa corporal desse caburé (41-80 g), confirmando outros relatos na literatura sobre o consumo de presas de tamanho considerável relativamente a essa espécie de Strigiformes. Embora a maioria dos autores em geral subestime o risco de predação das aves participantes de tumultos, este e outros relatos espalhados pela literatura demonstram que tais eventos não são tão insignificantes e podem ser fatais para as aves, além de proveitosos para o predador.

The feeding ecology of the maned wolf (Chrysocyon brachyurus) was studied from 1998 to 2002 in the Ecological Station of Itirapina, São Paulo State, southeastern Brazil, including estimates of prey number and biomass consumption. A total of 325 faecal samples was collected in the area. The species is omnivorous, with a broad diet including 68 species or morphospecies of fruits and animals. Armadillos (Dasypodidae), wolf's fruit (Solanum lycocarpum) and small mammals (mostly Clyomys bishopi) were the bulk of the diet, comprising 72.8 % of the total estimated biomass consumed (185,323.4 g). In terms of frequency of occurrence, on the other hand, only small mammals and other miscella-neous fruits yielded 43.4 % of the total occurrences (N = 1,054). Animal prey ranging from 0.01 and 0.1 Kg were the most captured category, resulting in 44.2 % of 507 captured animals. The maned wolf seems to be seasonally opportunistic, at least for fruits and insects, as indicated by the variation of the consumption of these items along the year. The higher consumption of fruits and animals characteristic of savannah can be an important factor to consider in future management plans for the species. A dieta do lobo-guará ( Chrysocyon brachyurus) foi estudada entre 1998 e 2002 na Estação Ecológica de Itirapina, Estado de São Paulo, incluindo estimativas de número de presas e biomassa ingerida. Um total de 325 amostras fecais foi coletado na área de estudo. A espécie pode ser considerada onívora, com uma dieta variada incluindo 68 espécies ou morfo-espécies de frutos e animais. Os tatus (Dasypodidae), fruta-de-lobo ( Solanum lycocarpum) e pequenos mamíferos (principalmente Clyomys bishopi) constituíram a base da dieta, com 72,8% do total de biomassa consumida (185.323,4 g). Por outro lado, em termos de freqüência de ocorrência, apenas os pequenos mamíferos e outros frutos compreenderam 43,4% do total de ocorrências (N = 1.054). Presas animais entre 0,01 e 0,1 Kg foram as mais consumidas, representando 44,2 % do total de 507 indivíduos capturados. O lobo-guará apresenta oportunismo sazonal pelo menos para frutos e insetos, a julgar pela variação no consumo desses itens nas diferentes estações do ano. O alto consumo de frutos e animais provenientes do cerrado deve ser levado em conta em planos futuros de manejo da espécie.

The influence of the golden lion tamarin (Leontopithecus rosalia) as a seed disperser was studied by monitoring two groups of tamarins from December 1998 to December 2000 (871.9 hours of observations) in a forest fragment in south-east Brazil. The tamarins consumed fruits of 57 species from at least 17 families. They ingested the seeds of 39 species, and 23 of these were put to germinate in the laboratory and/or in the field. L. rosalia is a legitimate seed disperser because the seeds of all species tested germinated after ingestion, albeit some in low percentages. These primates do not show a consistent effect in final seed germination, because they benefit some species while damaging others. Feces were examined for seeds that had been preyed upon or digested.