Pampas Fox Lycalopex Gymnocercus Research Articles

Natural history notes on Pampas Fox Lycalopex gymnocercus (Mammalia: Carnivora: Canidae) in the Paraguayan Chaco

We provide some natural history notes on the Pampas Fox Lycalopex gymnocercus from the Paraguayan Chaco. Information is presented on diet, distribution (with the first formal documentation of the species in the Oriental region), local beliefs, mortality, and possible play behavior. Photographic documentation of the existence of sarcoptic mange in wild foxes in the Paraguayan Chaco is also provided.

First record of the pampas fox Lycalopex gymnocercus (Fischer, 1814) at the north-central region of Paraná state, Brazil

Notas sobre Mamíferos Sudamericanos es una revista de la Sociedad Argentina para el Estudio de los Mamíferos (SAREM). Publica información acotada donde se describen nuevas localidades de registro, datos sobre comportamiento y aspectos ecológicos de mamíferos neotropicales.

RECORD OF A LEUCISTIC PAMPAS FOX LYCALOPEX GYMNOCERCUS (CARNIVORA: CANIDAE) IN NORTHEASTERN OF ARGENTINA

Leucism is a frequent chromatic mutation in mammals that causes partial or complete fur depigmentation. This type of mutation is interesting because they have physiological and ecological implications. We report here the first record of leucism in a pampas fox Lycalopex gymnocercus (Carnivora: Canidae), photographed using a camera trap in the northeast of the province of Corrientes, Argentina. Although cases of hypopigmentation are apparently very rare among pampas foxes, they could actually be more frequent than previously assumed. Given the ecological and physiological importance of these anomalies, researchers should report all records of this type in order to understand the degree to which these genetic variants are present in wild populations of different species of vertebrates.

Spatio-temporal interactions of carnivore species in a coastal ecosystem in Argentina

Land-sea interface is an ecotone where the intersection of marine and terrestrial ecosystems create unique ecological conditions for terrestrial mobile species and freshwater-adapted organisms to exploit marine-derived food resources. Mammalian carnivores play an important role in almost any ecosystem where they live due to their top-down (or trophic cascade) effects on prey species and primary producers, thus structuring ecosystems along varied food-web pathways. We use camera trapping to study the patterns of coexistence, habitat use and activity pattern of carnivores species in a coastal area in southern Buenos Aires province, Argentina. We were able to detect five of the seven species of Mammalian carnivores being the Pampas fox Lycalopex gymnocercus and Geoffroy's cat Leopardus geoffroyi the two most common. Geoffroy's cat seems to use more intensively those areas close to the shoreline, while we found little support of it for Pampas fox; which seems to use more inland areas. Congruently, we found evidence of a lack of spatial and, to a lower extent, temporal avoidance between the two most common carnivore species of our study area. Our findings support those previous studies indicating that the coastal dunes have an important role in the conservation of the biodiversity of Buenos Aires province. Wildlife conservation is compatible with carefully-designed ecotourism and limited infrastructure development and this may be a unique chance for the areas of Buenos Aires coast that have not been affected yet by poorly planned, conservation-unfriendly urbanization.

The Pampas Fox Lycalopex gymnocercus (Carnivora, Canidae) in the Late Pleistocene of Northern Uruguay

Canids are a very diverse and widely distributed group of carnivorous mammals. These animals entered South America in the early stages of faunistic interchange and later during the Pleistocene. However, the fossil record of these organisms is quite scarce on the continent, particularly in Uruguay. In the present contribution, two skulls associated with mandibles are described. Both materials were referred to as individuals of the Pampas fox Lycalopex gymnocercus, which was supported by morphological and morphometric analysis. These materials were found in late Pleistocene sediments (Sopas Formation) from different localities of northern Uruguay. Some aspects of their systematic and trophic dynamics are discussed. The remains of these animals have previously been listed but never described; thus, this material is the first fossil record reliably determined for this species in Uruguay.

FIRST RECORD OF PIEBALDISM IN Lycalopex gymnocercus (CARNIVORA, CANIDAE) IN THE PAMPA BIOME, SOUTHERN BRAZIL

Several cases of albinism, melanism, leucism and piebaldism in mammals have already been reported in the scientific literature. Such genetic mutations are important to be reported, because it can affect the ecological interactions of Pampas Fox individuals with piebaldism, such as predation and mating. Here we report the first case of piebaldism for the Pampas Fox Lycalopex gymnocercus (Carnivora, Canidae) , observed in a rural area within the municipality of Bage, Rio Grande do Sul state, Southern Brazil.

Summer habitat use and activity patterns of wild boar Sus scrofa in rangelands of central Argentina.

Biological invasions are one of the main components of human-caused global change and their negative impact on invaded ecosystems have long been recognized. Invasive mammals, in particular, can threaten native biodiversity and cause economic impacts in the region where they are introduced, often through a wide range of conflicts with humans. Although the wild boar, Sus scrofa, is considered by the IUCN as one of the 100 invasive species most damaging to biodiversity in the world, in Argentina there have only been a few studies focused on its ecology with most of them conducted in protected areas. In this study, we evaluated the effect of several factors related with human disturbance, landscape composition, degree of fragmentation and the presence of a potential competitor and a predator on the habitat use of wild boar using data from camera traps and site-occupancy modeling. Additionally, we described the daily activity pattern of the species and we studied the level of overlap with both a potential competitor and a predator. The sampling effort totaled 7,054 camera trap days. Farm density, proportion of shrubland and proportion of grassland with bushes were the detection variables included in the most supported model whereas proportion of grassland and capture rate of the Pampas fox Lycalopex gymnocercus were the occupancy variables included in the most supported model. However, the proportion of grassland was the only variable that showed statistically significant support in the averaged model, indicating that habitat use of wild boar in this area was significantly negatively affected by the level of grass cover. Wild boars were mostly nocturnal, with more activity between 21:00 and 3:00 and a peak around midnight. Wild boars showed a high level of overlap with the activity pattern of the Pampas fox and a low overlap with the activity pattern of the puma Puma concolor. Despite wild boar being introduced in Argentina a few decades ago, this study is the first landscape-scale research carried out in an agricultural landscape in Argentina and the first one based on camera-trapping data. Our study contributes valuable information that could be used to design strategies to reduce wild boar population or to minimize the damage caused by this invasive species in Argentina.

Adenoviruses of canine and human origins in stool samples from free-living pampas foxes (Lycalopex gymnocercus) and crab-eating foxes (Cerdocyon thous) in São Francisco de Paula, Rio dos Sinos basin.

The spread of enteric viruses of domestic animals and human beings to wild species can be facilitated by the resistance of these viruses on the environment and their ability to be transmitted by water and contaminated food. The health status of the populations of pampas foxes Lycalopex gymnocercus) and crab-eating foxes (Cerdocyon thous) is largely unknown and the landscapes occupied by these animals in southern Brazil have been threatened by human occupation and expansion of agriculture. In this work, the search of genomes of human and canine adenoviruses in feces from these wild carnivores was used to track the dissemination of domestic animals and human pathogens to the free-living populations in a wildlife reserve located in southern Brazil. This was performed by virus-specific differential real-time polymerase chain reactions (qPCR) on stool specimens, avoiding capture and additional stress to the animals. Genus-specific conventional reverse-transcriptase PCR (RT-PCR) was complementarily performed aiming the detection of enteroviruses (EV) and rotaviruses (RV) on these same samples. HAdV genomes were found on 14 out of the 17 (82.35%) stool samples analysed, whereas CAV was found co-infecting 5 of these samples. RV genomes were detected on 7 of the 17 samples (41.18%) and all samples were negative for EV. The results point to the dispersion of HAdV and RV at a high rate to these species of South American wild carnivores, which can be an effect of growing anthropisation of the habitat of these animals.

Dissimilar responses of the Gray brocket deer (Mazama gouazoubira), Crab-eating fox (Cerdocyon thous) and Pampas fox (Lycalopex gymnocercus) to livestock frequency in subtropical forests of NW Argentina

This study represents the first analysis of livestock influence over individual mammal species in NW Argentina forests. Through camera-trapping, I found a negative correlation between frequencies of occurrence of livestock (sheep, goats and cattle) and Gray brocket deer Mazama gouazoubira, and a modification of the daily activities patterns of the latter according to changes in density of the former. However, no evident associations between Crab-eating fox Cerdocyon thous and Pampas fox Lycalopex gymnocercus frequencies and livestock were found. This study provides insights on the effects of extensive ranching over mammal species in NW forests of Argentina, where this activity is of major importance among forests inhabitants.