Information about resource partitioning among small cat species that live in sympatry in South America is fairly incomplete. Knowledge about feeding habits is essential for understanding the role of ...these predators in the environment, the impact on prey populations, and potential competition among themselves and with other carnivores. This study aimed to describe and compare the diet of four sympatric small cats in the grasslands of southern Brazil. We analysed the stomach contents of 37 Geoffroy's cats (Leopardus geoffroyi), 27 margays (Leopardus wiedii), 14 pampas cats (Leopardus colocola), and 20 jaguarundis (Herpailurus yagouaroundi) obtained as road kill in the Brazilian Pampa in southern Brazil. Small mammals were the most representative class consumed by all cats, followed by Aves, Reptilia, and Amphibia. Some items, such as rodents Cavia aperea, Akodon sp., Oligoryzomys sp. and Passeriformes were consumed by all cat species. Niche overlap varied widely, from 10% (margay x jaguarundi) to 92% (jaguarundi x pampas cat). Niche breadth indicated that jaguarundi were the most specialized of the cats (Bsta = 0.24) in this region, with a diet closely associated to C. aperea. Margay consumed more items associated with arboreal behaviour than other cat species, but consumed more terrestrial items than arboreal ones. The pampas cat consumed mostly terrestrial species associated with open fields. Geoffroy's cat consumed mammals found in a diversity of habitats, indicating high ecological flexibility. Species with more similarity in diet such as jaguarundi and pampas cat probably present temporal segregation in activity. In conclusion, despite their habitat and diet similarities, these four species explore distinct microhabitats by foraging different prey groups, what favor them to live in sympatry.
Wild boar are considered one the world's worst invasive species and linked to biodiversity loss, competition for resources, predation of native species, and habitat modifications. In this study, we ...use camera traps to evaluate whether the invasive wild boar had an effect on the medium-sized mammal community of a protected area in southern Brazil. Based on photographic records, we evaluated whether the presence and relative abundance of wild boar was associated with a decrease in diversity or change in activity of medium-sized mammals. All comparisons were made between samples where wild boar were present or absent. The records of each camera during a season were considered a sample. The wild boar was the fourth most common species in the study area being present in 7.8% of the photographic records. The species richness of mammals was not negatively affected by the occurrence of wild boar and most common species did not exhibit changes in the daily activity pattern. However, we recorded an increase in the time elapsed between an observation of wild boar and the record of the next species relative to the average latency period observed among other mammalian species. This average latency period was similar to that observed in the case of large predators such as Puma, and its increase could be reflective partly of the avoidance of native species to wild boar. Nevertheless, our results show that the effect of invasive wild boar on the mammal community is not large as expected.
The lesser grison (
) is one of the least known carnivores in the Neotropical region. Its wide geographical occurrence and range of habitats could lead to morphological variations along its ...distribution. So, this study aimed to investigate the variation in skull shape and size of this species, by testing the existence of ecotypes adapted to their respective environments (Uruguayan savanna and Atlantic Forest), as well as its relationship with selected abiotic variables.
The skulls of 52 museum specimens were photographed in the ventral, dorsal, and lateral views, and were analyzed using geometric morphometric techniques.
We found sexual size dimorphism, with males being larger than females. The shape variation between sexes, as well as between ecoregions, is mostly explained by the effect of allometry. The specimens from Uruguayan savanna are larger than the ones from the Atlantic Forest. Size variation was also significantly correlated to latitude, temperature and precipitation patterns. No correlation between skull shape with geographical distance was detected.
Morphometric measurements and diet data of lesser grison in regions from higher latitudes than our sampling show a tendency to heavier individuals, and the consumption of bigger prey compared to Uruguayan savanna. The results indicated the smaller specimens associated to low variability in annual temperature, congruent to Atlantic Forest region. An explanation for observed variation may be related to the "resource rule" but, due the minimal natural history information regards this species, we can just speculate about this.
Geoffroy’s cat (
Leopardus geoffroyi
) is a small neotropical felid that has been the focus of a few dietary studies in the Brazilian Pampa. In order to better understand its trophic ecology, it is ...essential to accurately determine its diet and to evaluate potential relationships between prey composition and habitat suitability. To achieve this, we employed both DNA barcoding and morphology to identify prey items and compared the effectiveness of these methods. We then estimated the habitat suitability of Geoffroy’s cat and compared it with the suitability of the most important prey species in the region. DNA barcoding was found to be more accurate at identifying prey species. Analysis of the most important prey species revealed that Geoffroy’s cat in the Brazilian Pampa has a diverse diet preying primarily on small mammals, with
Cavia aperea
,
Oligoryzomys nigripes
, and
Oligoryzomys flavescens
being the most important species. Geoffroy’s cat had higher suitability in habitats with intermediate vegetation cover. Our best-fit model in the GLM analysis suggested that the habitat suitability of the three prey species combined explain better the variations in suitability of the predator, with two species positively and one negatively related to the predator’s suitability. This suggests that Geoffroy’s cat exhibits a generalist behavior, preying on available species within its distribution. By combining a dietary study with efficient prey identification and habitat suitability analysis, we were able to gain a more comprehensive understanding of the complex ecological network of this felid.
The canid genus Lycalopex comprises six recently diversified South American species whose evolutionary relationships have been remarkably challenging to resolve. We analyzed 6000 bp of mitochondrial ...DNA (mtDNA) from 55 Lycalopex individuals (L. sechurae = 4, L. culpaeus = 7, L.griseus = 8, L.gymnocercus = 17, L.vetulus = 13 and L. fulvipes = 6), and nine specimens from the closely related species Cerdocyon thous, Chrysocyon brachyurus and Speothos venaticus, to reconstruct their phylogenetic relationships, estimate the support for species-level monophyly, and date their divergences. In addition, we also sequenced seven nuclear segments from the same taxa. Three different phylogenetic approaches converged on the same mitochondrial topology with strong support for most nodes. All species were confirmed to be monophyletic for mtDNA, except for one intriguing case in which two L. vetulus individuals carried L. gymnocercus haplotypes, potentially implying a case of interspecies admixture. L. vetulus was the first species to diverge (ca. 1.2 Mya), followed by L. sechurae and then L. gymnocercus. The most internal group comprised L. griseus and the sister-species L. culpaeus and L. fulvipes, which diverged around 430,000 years ago in southern Argentina or Chile. The analysis of nuclear markers revealed several examples of intra-specific variation coupled with lack of species monophyly, consistent with pervasive incomplete lineage sorting and/or hybridization in this recent radiation. Our results provide robust mitochondrial resolution of this challenging radiation, and illustrate the difficulty of attaining similar success with traditional nuclear markers.
Between 2000 and 2010, digestive tracts collected from carnivore carcasses found in southern Brazil were analyzed to determine the frequency and proportion of items constituting the diets of each ...species. Material was collected and analyzed from 194 animals of 10 species:
,
(Canidae),
(Procyonidae),
(Mustelidae),
(Mephitidae),
,
,
,
, and
(Felidae). Most of these species are sympatric, which makes them potential competitors when sharing, to a greater or lesser degree, the same resources. The food niche breadth was relatively narrow, demonstrating that even generalist species, such as the crab-eating raccoon, used food resources rather unequally. An extensive overlap (>90%) in food niches was found among the cat species, the grison, and the Pampas fox, which had diets based on rodents. Crab-eating raccoons occupied a different food niche, based on aquatic or semiaquatic prey and fruits.
was unique in exploiting arthropods and insect larvae as basic dietary items.
The hoary fox (Lycalopex vetulus) is the only species of the Canidae (Mammalia: Carnivora) endemic to Brazil, and so far has been the target of few genetic studies. Using microsatellites and mtDNA ...markers, we investigated its present genetic diversity and population structure. We also tested the hypothesis that this species currently hybridizes with the pampas fox (L. gymnocercus), as suggested by previous mtDNA data from two individuals. We collected tissue and blood samples from animals representing most of the two species' distributions in Brazil (n = 87), including their recently discovered geographic contact zone in São Paulo state. We observed that the hoary fox exhibits high levels of genetic diversity and low levels of population structure. We identified six individuals from São Paulo state with clear evidence of hybridization based on introgressed pampas fox mtDNA and/or admixed microsatellite genotypes (three individuals bore both types of evidence). These results demonstrate the existence of admixed individuals between hoary and pampas foxes in southeastern Brazil, representing the first identified case of inter-species admixture between native South American canids. We discuss our findings in the context of the evolutionary history of these foxes and address potential conservation implications of this interspecies hybridization process.
The lesser anteater Tamandua tetradactyla is possibly the most common member of the order Pilosa and occurs in almost all tropical environments in South America. Although commonly recorded in mammal ...inventories, this species is not abundant, and little is known about its ecology. The food habits of the species are mainly based on ants, but the type and contribution of other arthropods to the diet, especially termites, remains a subject little discussed in the literature. In the present study, we carried out a comprehensive assessment of stomach contents of 16 roadkilled anteaters found in grassland ecosystems in the Brazilian Pampa. We found 73,890 prey, with ant and termite species being the most representative dietary resources. Ants were present in 100% of the stomachs and represented more than 85% of all items consumed, totaling 34 species. Termites were present in 62.5% of the stomachs and represented 14.6% of all items consumed and, summed up five species. We also found six other arthropod taxa but with an insignificant proportion of the biomass intake. Our results contribute to increase knowledge on T. tetradactyla feeding habits in the subtropical grasslands of Southern Brazil.
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