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Chaves, O. M.

Publications and source records attributed to Chaves, O. M..

3 recordsLinked to original sources

Plant diversity in diet of Costa Rican Primates in contrasting habitats: a meta-analysis

In human-modified tropical landscapes, the survival of arboreal vertebrates, particularly primates, depends on their plant dietary diversity. Here, we assessed diversity of plants included in the diet of Costa Rican non-human primates, CR-NHP (i.e. Alouatta palliata palliata, Ateles geoffroyi, Cebus imitator, and Saimiri oerstedii) inhabiting different habitat types across the country. Specifically, we assessed by analyzing 37 published and unpublished datasets: (i) richness and dietary -plant diversity, (ii) the {beta}-diversity of dietary plant species and the relative importance of plant species turnover and nestedness contributing to these patterns, and (iii) the main ecological drivers of the observed patterns in dietary plant . Diet data were available for 34 Alouatta, 16 Cebus, 8 Ateles, and 5 Saimiri groups. Overall dietary plant species richness was higher in Alouatta (476 spp.), followed by Ateles (329 spp.), Cebus (236 spp.), and Saimiri (183 spp.). However, rarefaction curves showed that -diversity of plant species was higher in Ateles than in the other three primate species. The {gamma}-diversity of plants was 868 species (95% C.I.=829-907 species). The three most frequently reported food species for all CR-NHP were Spondias mombin, Bursera simaruba, and Samanea saman. In general, plant species turnover, rather than nestedness, explained the dissimilarity in plant diet diversity ({beta}sim> 0.60) of CR_NHP. Finally, primate species, habitat type (life zone and disturbance level) and, to a lesser degree, sampling effort were the best predictors of the dietary plant assemblages. Our findings suggest that CR-NHP diets were diverse, even in severely-disturbed habitats.

animal behavior and cognition↗

Wildlife is imperiled in peri-urban landscapes: threats to arboreal mammals

Urbanization and deforestation impose severe challenges to wildlife, particularly for forest-living vertebrates. Understanding how the peri-urban matrix impacts their survival is critical for designing strategies to promote their conservation. We investigated the threats faced by brown howler monkeys (Alouatta guariba clamitans) in peri-urban regions of Rio Grande do Sul (RS) and Santa Catarina (SC) states, southern Brazil, by compiling negative interaction events (hereafter NIE) reported over more than two decades. We assessed the major NIEs, their distribution among age-sex classes, and the predictors of NIE-related mortality. After 20+ years of monitoring, we compiled 540 NIEs (RS = 248 and SC = 292). Electrocution by power lines was the most frequent cause of death or injury (37%), followed by dog attack (34%), vehicle collision (17%), and human mistreatment (12%). The occurrence of lethal injuries ranged from 5% to 69% depending on the type of NIE and on which state it occurred in. The overall post-NIE mortality was 56%. Adults of both sexes were the most affected individuals in both study regions. The minimal adequate GLM model explained 83% of the variation in NIE-related mortality. State, NIE type, and age-sex class were the main predictors of mortality. Overall, mortality was lower in SC and higher among adult females than in the other classes. We found that the survival of brown howler monkeys in the forest-urban interface is constrained by both the urban infrastructure and the growing interactions with humans and domestic and stray dogs (Canis familiaris). We propose the placement of aerial bridges, road signs and speed bumps in areas of frequent animal crossing, the sterilization of stray dogs, and the sensitization of local inhabitants on the importance of respecting and protecting wildlife to reduce their NIEs with humans and domestic animals in the forest-urban interface.

ecology↗

Leaf and flower consumption modulate the drinking behavior in a folivorous-frugivorous arboreal mammal

Water is vital for the survival of any species because of its key role in most physiological processes. However, little is known about the non-food-related water sources exploited by arboreal mammals, the seasonality of their drinking behavior and its potential drivers (including diet composition, temperature, and rainfall). We investigated this subject in 14 wild groups of brown howler monkeys (Alouatta guariba clamitans) inhabiting small, medium, and large Atlantic Forest fragments in southern Brazil. We found a wide variation in the mean rate of drinking among groups (range=0-16 records/day). Streams (44% of 1,258 records) and treeholes (26%) were the major types of water sources, followed by bromeliads in the canopy (16%), pools (11%), and rivers (3%). The type of source influenced whether howlers used a hand to access the water or not. Drinking tended to be evenly distributed throughout the year, except for a slightly lower number of records in the spring than in the other seasons, but it was unevenly distributed during the day. It increased in the afternoon in all groups, particularly during temperature peaks around 15:00 and 17:00. We found via generalized linear mixed modelling that the daily frequency of drinking was mainly influenced by flower (negatively) and leaf (positively) consumption, whereas fruit consumption, fragment size, rainfall, and mean ambient temperature played negligible roles. The influence of leaf consumption is compatible with the metabolite detoxification hypothesis, which states that the processing of this fibrous food requires the ingestion of larger volumes of water to help in the detoxification/excretion of its metabolites. In sum, we found that irrespective of habitat size and climatic conditions, brown howlers seem to seek a positive water balance by complementing preformed and metabolic water with drinking water, even when it is associated with a high predation risk in terrestrial sources.

animal behavior and cognition↗