RESUMO
The dietary ecology of a species can provide information on habitat requirements, food resources, and trophic interactions, important to guide conservation efforts of wildlife populations in endangered habitats. In this study, we investigated the dietary ecology of bearded capuchin monkeys (Sapajus libidinosus) in Brasilia National Park, in the endangered Cerrado biome of central Brazil. To obtain diet composition and evaluate the role of these primates as seed dispersers of local tree species, fecal sample collections and feeding observations were performed for a 7-month period. To determine whether seeds germinated better after passing through a primate gut, we conducted germination trials with (i) pulped seeds from trees, (ii) depulped seeds from trees, (iii) seeds from feces planted with feces, and (iv) seeds from feces planted without feces. During experimental procedures, 7308 seeds from 8 families and 10 species were planted. We found that S. libidinosus spent more time feeding on fruits than on any other food item and the diet consisted of 33 plant species from 21 families. However, 20% of their diet consisted of anthropic food. Most seeds planted with feces germinated faster compared to seeds in other experimental treatments, suggesting that passing through the gut and being deposited with fecal material is advantageous. The bearded capuchins also defecated many medium- (5 species) and large-sized (2 species) seeds that may be inaccessible to smaller arboreal frugivores. The results obtained emphasize the important role of bearded capuchins as seed dispersers for the maintenance and conservation of the endangered Cerrado biome.
Assuntos
Cebinae , Dieta , Fezes , Dispersão de Sementes , Sementes , Animais , Dieta/veterinária , Brasil , Cebinae/fisiologia , Parques Recreativos , Comportamento Alimentar , Germinação , Masculino , Espécies em Perigo de Extinção , FemininoRESUMO
The use of tools played a central role in human culture and evolution. Early studies with apes demonstrated the tool use; however, currently the works have focused on Platyrrhine, particularly capuchin monkeys. Blonde capuchin monkeys, Sapajus flavius, have been observed using sticks to fish for termites in the Atlantic Forest, where this species has been extensively studied. In this study, we presented the first evidence of stone tool use by the blonde capuchin monkeys, as well as the dimensions and weight of these tools. We gathered data from three areas of Caatinga dry forest where we discovered this new tool use among the species. The mean weight of the hammers was 475.7 g (± 142 SD). The mean height of the anvils was 48.3 cm (± 18.7 SD), while the mean surface area of the anvils was 1.2 m2 (± 0.4 SD). We identified fruits and/or nuts from three plant species-Prunus dulces, Cnidoscolus quercifolius, and Syagrus coronate-near the anvils at the study sites. Additionally, we passively observed six instances of stone tool use by blonde capuchin monkeys. Their use of stones to crack encased foods mirrored behaviors previously reported in Sapajus libidinosus, a species well known for using stone tools to exploit hard nuts. Our findings place blonde capuchin monkeys among the list of primates that utilize stones as tools, highlighting the species' adaptability in exploiting resources within the Caatinga. Long-term studies are essentials to comprehend the use pattern of stone tools (across both general and seasonal perspectives) and the influence of variables, such as fruit hardness, distance to watercourses, and fruit availability on the use of this technology by this primate.
Assuntos
Sapajus , Comportamento de Utilização de Ferramentas , Animais , Comportamento Alimentar , Brasil , Feminino , Masculino , Frutas , Nozes , Cebinae/fisiologiaRESUMO
Platyrrhines consume many species of arthropods in the order Orthoptera. Some species of orthopterans can produce chemical defenses that render them toxic or unpalatable and thus act as predator deterrents. These species include the stick grasshoppers (family Proscopiidae), which are widely distributed in the Caatinga biome in northeastern Brazil, which comprises part of the distribution of capuchin monkeys. Capuchin monkeys are omnivores and consume a wide variety of foods, including unpleasant-tasting, potentially toxic items, which they need to learn how to process. We describe the processing of stick grasshoppers (Stiphra sp.) by wild capuchin monkeys (Sapajus libidinosus) that live in Serra da Capivara National Park, Brazil, and compare how individuals of different age classes handle these potentially toxic food items. S. libidinosus predominantly avoided consuming the digestive tract, which contains toxic compounds, when feeding on stick grasshoppers. Immatures took longer than adults to process the stick grasshoppers, indicating that capuchins need to learn how to process the toxic digestive tract of these prey to avoid consuming it.
Assuntos
Gafanhotos , Animais , Gafanhotos/fisiologia , Brasil , Feminino , Masculino , Comportamento Alimentar , Cebinae/fisiologiaRESUMO
Primates employ different tools and techniques to overcome the challenges of obtaining underground food resources. Humans and chimpanzees are known to tackle this problem with stick tools and one population of capuchin monkeys habitually uses stone tools. Although early hominids could have used stones as digging tools, we know little about when and how these could be useful. Here, we report a second primate population observed using stone tools and the first capuchin monkey population to habitually use the 'stick-probing' technique for obtaining underground resources. The bearded capuchin monkeys (Sapajus libidinosus) from Ubajara National Park, Brazil, use 'hands-only' and 'stone-digging' techniques for extracting underground storage organs and trapdoor spiders. Males also use 'stick-probing' and 'stone-stick' techniques for capturing trapdoor spiders. Tool use does not increase success in obtaining these resources. Stone-digging is less frequent in this population than in the only other known population that uses this technique. Females use stones in a lower proportion of their digging episodes than males in both populations. Ecological and cultural factors potentially influence technique choice and sex differences within and between populations. This population has a different pattern of underground food exploration using tools. Comparing this population with others and exploring the ecological and cultural factors under which capuchin monkeys employ different tools and techniques will allow us to better understand the pressures that may have shaped the evolution of those behaviors in primates.
Assuntos
Cebinae , Comportamento Alimentar , Comportamento de Utilização de Ferramentas , Animais , Masculino , Feminino , Comportamento Alimentar/fisiologia , Cebinae/fisiologia , Brasil , Cebus , AlimentosRESUMO
The progressive growth of urban environments has increasingly forced populations of nonhuman primates to coexist with humans in many cities, which has resulted in problems such as behavioral alterations, conflicts with humans, and threats to the health of the monkeys, due to their consumption of anthropogenic foodstuffs. These anthropogenic foods, which are rich in calories, are the principal driver of the proximity between humans and primates, even though the acquisition of these foods tends to be risky for the monkeys and involve a variety of challenges derived from specific features of the urban environment. The present study evaluated the success/risk relationship of foraging for anthropogenic food by tufted capuchins (Sapajus libidinosus) in Brasília National Park. The data were analyzed using a binary logistic regression, with the backward-stepwise Wald method, to investigate the factors related to the foraging success of the capuchins, considering variables such as their sex and age, the type of approach and its context, and interactions with humans. The capuchins were influenced by the anthropogenic context, which affected their foraging strategies and diet. Interactions with humans reduced the success of foraging for anthropogenic foods. Conflicts between humans and the capuchins were common, especially in the context of access to food. The capuchins thus preferred to access feeding resources directly, probably due to the reduced human interference, which resulted in greater foraging success for unattended food brought by park visitors and the raiding of trash cans. Based on the observed behavior patterns, a number of measures can be proposed to mitigate these conflicts. These recommendations include not bringing food into areas frequented by the capuchins, not reacting to approaching animals, and removing all trash generated during a visit. A cleaning team dedicated to the maintenance of the visitation area free of anthropogenic waste is also be recommended.
Assuntos
Cebinae , Comportamento Alimentar , Parques Recreativos , Animais , Brasil , Masculino , Feminino , Humanos , Cebinae/fisiologia , Interação Humano-Animal , Dieta/veterináriaRESUMO
BACKGROUND: There are few studies on the physiology and haematology of rescued bearded capuchin monkeys. These are necessary to better understand the health and welfare status of the animals, including when performing reintroductions, and to avoid zoonoses. METHODS: We aimed to obtain physiological and haematological values, morphometry and parasitological status of 26 bearded capuchins in two rescue centres in Northeast Brazil. RESULTS: We found sex- and age-related differences in respiratory rate, body weight and body mass index, but not haematology. The haematological values obtained were significantly different from published data but within the reference intervals for the species. Animals infected with Ancylostoma spp. had significantly lower values in the parameters: haemoglobin concentration, mean corpuscular volume and mean corpuscular haemoglobin concentration than non-infected individuals. CONCLUSION: Physiological and haematological values of rescued capuchins were similar to those found in previous studies. Ancylostomiasis appears to cause alterations to haematological values of this species.
Assuntos
Cebinae , Cebus , Animais , Brasil , Cebinae/fisiologia , HaplorrinosRESUMO
RATIONALE: This study analyzes variability in the diets of wild bearded capuchin monkeys, Sapajus libidinosus, by analyzing stable carbon (δ13 C) and nitrogen (δ15 N) isotope ratios and elemental concentrations (%C and %N) of fecal samples and food items. Developing isotopic and elemental correlates for diets of habituated subjects is a necessary step towards applying similar methods to interpret diets of unhabituated or cryptic subjects. METHODS: Fecal samples from wild capuchins and their foods were collected at Fazenda Boa Vista, Brazil. Fecal samples from laboratory-housed Sapajus spp. and their foods were analyzed to establish diet-feces offsets for δ13 C, δ15 N, %C, and %N. Samples were dried, powdered, and measured for isotopic and elemental values. A Bayesian mixing model commutes isotopic and elemental data from wild capuchins into likely proportions of different food categories. RESULTS: The captive study shows small diet-feces spaces for Sapajus spp. of -0.8 ± 0.7 for δ13 C, -0.2 ± 0.4 for δ15 N, -6.1 ± 1.7% for %C, and -1.0 ± 0.6% for %N. The wild study shows omnivorous diets based on C3 , C4 , and CAM plants, and fauna. Subject diets are highly varied within and between days. Fecal data show age-related differences in diet and crop-raiding. There is no consistent isotopic or elemental difference between mothers and infants. CONCLUSIONS: Fecal stable isotope and elemental evidence employed in a Bayesian mixing model reflects the highly varied diets of capuchin monkeys in an isotopically heterogeneous environment. The isotopic and elemental variability reported here will aid similar diet reconstructions among unhabituated subjects in the future, but precludes tracking weaning isotopically among capuchins in this environment.
Assuntos
Cebinae/fisiologia , Dieta/veterinária , Comportamento Alimentar/fisiologia , Animais , Brasil , Isótopos de Carbono/análise , Fezes/química , Feminino , Masculino , Espectrometria de Massas , Isótopos de Nitrogênio/análiseRESUMO
Shifting to fallback food (FBF) consumption and crop raiding are behavioral adjustments that support primates' ability to endure in human-altered habitats. Nutritional models predict that the consumption of preferred foods leads to increased competition, while consumption of staple fallback foods results in decreased competition. We analyzed the competitive regime faced by individuals in a group of 133 blond capuchin monkeys (Sapajus flavius), an endangered species that inhabits a 270-ha fragment of Atlantic forest in northeast Brazil. During the study year, quantitative analyses show that fruits were a preferred food, while sugarcane was used as a staple FBF. As predicted by primate fallback foraging models, the consumption of sugarcane helped the group to survive in this fragment by providing these animals with half of the food they consumed throughout the year. Contrary to predictions, group dispersion increased with greater fruit abundance, while direct competition peaked during the consumption of sugarcane. We suggest that, although it is abundant and scattered in the area, the long handling time required to process sugarcane before consumption facilitates the direct competition. Overall, the pattern found indicates that consumption of a staple FBF does not directly translate into decreased competition and increased stability of social groups in forest fragments.
Assuntos
Cebus/fisiologia , Comportamento Competitivo , Comportamento Alimentar , Saccharum , Animais , Brasil , Cebinae/fisiologia , Produtos Agrícolas , Espécies em Perigo de Extinção , Feminino , MasculinoRESUMO
BACKGROUND: Establish baseline values for ophthalmic diagnostic tests in Sapajus libidinosus. METHODS: Ophthalmic diagnostic tests, namely Schirmer tear test 1 (STT-1), intraocular pressure (IOP), B-mode ultrasound, culture of the bacterial conjunctival microbiota, and conjunctival exfoliative cytology, were performed in 15 S. libidinosus. RESULTS: Mean values found were as follows: 2.50 ± 2.94 mm/min for the STT-1; 13.3 ± 3.32 mm Hg for the IOP; 2.47 ± 0.41 mm for the depth of the anterior chamber; 2.86 ± 0.96 mm for the axial length of the lens; 10.97 ± 0.48 mm for the depth of the vitreous chamber; and 16.32 ± 1.24 mm for the axial length of the eyeball. The bacterial genus most frequently found was Staphylococcus spp. Conjunctival cytology showed intermediate epithelial, squamous superficial epithelial, and keratinized cells. CONCLUSIONS: Determination of baseline values for eye measurements and ophthalmic tests will assist in the diagnosis of eye diseases in S. libidinosus monkeys.
Assuntos
Cebinae/fisiologia , Técnicas de Diagnóstico Oftalmológico/veterinária , Testes Diagnósticos de Rotina/veterinária , Oftalmopatias/veterinária , Fenômenos Fisiológicos Oculares , Animais , Conjuntivite Bacteriana/diagnóstico , Conjuntivite Bacteriana/veterinária , Técnicas de Diagnóstico Oftalmológico/instrumentação , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Oftalmopatias/diagnóstico , Feminino , Pressão Intraocular , Masculino , Valores de ReferênciaRESUMO
Females across a range of animal taxa produce vocalizations and signals uniquely associated with periods of mating. While such signals may ultimately function to increase female attractivity to males, conflicting findings challenge the extent to which these signals co-vary in accordance with the probability of conception. Female black capuchin monkeys (Sapajus nigritus) display an elaborate repertoire of both vocal and visual components as part of their socio-sexual behavior, and previous analyses have shown that the rates of production of visual, but not vocal, components provide graded information on female ovulation. It remains possible, however, that the acoustic parameters of these sexual calls, rather than their rate of productions, co-vary with female fertility. To test this, we analyzed structural and temporal call parameters from estrous calls and post-copulatory calls recorded over five consecutive mating seasons in 12 sexually mature females at Iguazú National Park, Argentina. Calls given during the fertile phase of the female ovarian cycle were compared with those given during the non-fertile phase, as determined by profiles of female reproductive hormones. Similarly, within the fertile phase, we tested whether temporal or spectral acoustic parameters of calls gradually change with the approach of ovulation. We did not find any significant relationship between call parameters and the two measures of female fertility in either female estrous calls or post-copulatory calls. However, some differences between pre- and post-copulatory calls were apparent. Overall, our results indicate that sexual calls in black capuchin females do not provide precise information about the timing of ovulation, but may allow listeners to make probabilistic inferences about whether copulations have taken place. This, combined with previous findings, suggests that females in our study may use signals in different modalities to convey information about their fertility and sexual behavior with varying degrees of precision.