Lycalopex Griseus Research Articles

Mapping the distribution and risk factors of Anaplasmataceae in wild and domestic canines in Chile and their association with Rhipicephalus sanguineus species complex lineages

Anaplasma platys and Ehrlichia canis are members of the Anaplasmataceae family that cause disease in dogs and are mainly transmitted by Rhipicephalus sanguineus species group ticks. We performed a cross-sectional study on these pathogens across six bioclimatic regions of Chile, including 719 free-ranging rural dogs, 132 Andean foxes (Lycalopex culpaeus), and 82 South American gray foxes (Lycalopex griseus). Dog and fox blood samples were first screened for DNA of Anaplasmataceae followed by two Ehrlichia-specific protocols. Antibodies against Anaplasma sp. and E. canis were assessed by immunofluorescence in dogs. Ectoparasites were collected and identified, with the determination of the lineages of the Rhipicephalus sanguineus species group by molecular and phylogenetic analyses. Finally, potential risk factors for infection were investigated across the different bioclimatic regions and host species. All DNA amplicons obtained from the screening protocol corresponded to Anaplasma platys. The occurrence of both A. platys DNA and antibodies was confirmed in all six bioclimatic regions, except for regions at high altitude and/or without either R. sanguineus species group lineage present. Dogs infested with R. sanguineus ticks were significantly more prone to be infected and exposed to Anaplasma spp. Prevalence of DNA was significantly higher in juvenile (19%) than in adult dogs (9%), whereas the opposite was found for seroprevalence (19% versus 35%, respectively). Overall prevalence of A. platys DNA was higher in dogs (11%) than in foxes (4%), probably owing to markedly lower tick infestations in the foxes. Ehrlichia canis DNA was not detected in any sample, and antibodies against this pathogen were detected only in four dogs, in areas with both R. sanguineus lineages present. Free-ranging dogs in Chile could be favoring the maintenance of A. platys in all areas suitable for its tick vector. Although apparently infrequent, spillovers from dogs to foxes may be taking place and should be considered in management plans in Chile.

Domestic Dogs and Wild Foxes Interactions in a Wildlife-Domestic Interface of North-Central Chile: Implications for Multi-Host Pathogen Transmission.

Domestic dogs (Canis familiaris) often cohabite at interfaces shared by humans and wildlife, interacting with wild canids as predators, prey, competitors and reservoirs of several multi-host pathogens, such as canid-borne micro and macro parasites that could impact on wildlife, livestock and public health. However, spatio-temporal patterns of indirect interactions as promoters of pathogen transfer between domestic and wild canids are largely unknown. In this study, we used camera traps to describe the activity patterns and habitat use of dogs, chilla (Lycalopex griseus) and culpeo (Lycalopex culpaeus) foxes and identify the local-scale factors that may affect the frequency of dog-fox interactions through an anthropization gradient of the Coquimbo region, Chile. We assessed local-scale variables that may predict the number of interactions between dogs and foxes, and compared the time interval between dog-culpeo and dog-chilla interactions. Our findings suggested that closeness to urbanized zones predicts the frequency of indirect interactions between dogs and foxes. We found higher number of dog-fox interactions (60 interactions) at a periurban site adjacent to two coastal towns (Tongoy and Guanaqueros), compared to other two more undisturbed sites (12 interactions) increasingly distanced from urbanized areas. We showed that dogs interacted more frequently with chilla foxes (57 interactions) than with culpeo foxes (15 interactions), and the first interaction type occurred almost exclusively at the periurban site, where dogs and chillas were more frequently detected than in the other sites. We detected a marked temporal segregation between dogs and foxes, but dog-chilla interactions resulted in shorter time intervals (2.5 median days) compared to dog-culpeo interactions (7.6 median days), suggesting a higher potential risk of pathogen spillover between the first species pairing. Based on previous studies, we suggest periurban zones may constitute a potential focus of pathogen exposure between dog and fox populations in the study area. Our research contributes to improving the knowledge on the spatio-temporal patterns of interspecific contact between invasive and native carnivores within the context of multi-host pathogen dynamics. Our outcomes will inform theoretical epidemiological models designed to predict and minimize the contact risk between domestic and threatened species, guiding effective control strategies at the wildlife-domestic interface.

Seasonal variation in the diet of two predators in an agroecosystem in southern–central Chile

In ecosystems, seasonal fluctuations in the availability of resources can promote effects on species with similar trophic requirements, increasing the probability of interspecific competition. This scenario becomes more evident in human–dominated landscapes where homogenization of space can contribute to the shortage of resources, modifying species feeding behavior to an uncertain degree. Understanding how these species modify their feeding habits within the context of habitat transformation is of special interest. We evaluated the diversity of prey and overlap for two predators, the chilla fox Lycalopex griseus and the barn owl Tyto alba, during three seasons in 2018 (winter, spring and summer). The study was based on the analysis of feces and pellets in a landscape with agricultural predominance in Southern–central Chile. We found the chilla fox had a generalist dietary profile, feeding on a broad spectrum of prey, with predominance of lagomorphs and, to a lesser extent, rodents. In contrast, the diet of the barn owl mainly consisted of small rodents, with little variation across seasons. Analyses of dietary overlap showed fluctuations during the periods surveyed, with a maximum value in winter and a minimum value in spring. Variations in the consumption of prey based on their size could facilitate their coexistence in the study area.

Inferring Species Interactions from Long-Term Monitoring Programs: Carnivores in a Protected Area from Southern Patagonia

Protected areas recently created in Argentina often include previously degraded lands, such as sheep ranches in the Patagonian deserts. We show the results of a 14-year monitoring program of three formerly persecuted carnivores, the culpeo fox (Lycalopex culpaeus), the South American grey fox (Lycalopex griseus) and the puma (Puma concolor), in two abandoned sheep ranches that were incorporated into a Patagonian national park approximately 25 years ago. The culpeo fox population underwent an average annual decline of 10–23%, whereas the grey fox and puma populations increased at an average annual rate of 7% and 19%, respectively. The grey fox’s increasing trends were strongly correlated with the decline of the culpeo fox, whereas the correlations between the fox and puma trends were weaker. Culpeo fox decline was stronger in the ranch where sheep and predator controls had been removed earlier. These relationships between species trends support the competitive release hypothesis, assuming that puma competition with the culpeo fox for trophic resources is stronger than competition with the grey fox, and that the puma can exclude culpeo foxes through interference. Species trends suggest a competitive hierarchy between fox species, with grey fox being the inferior competitor. However, mechanisms other than competition could not be discounted. Our study illustrates how long-term monitoring of interacting species allows a better understanding of ecological processes and wildlife ecology.

Endoparasitic fauna of two South American foxes in Chile: Lycalopex culpaeus and Lycalopex griseus.

Native foxes face serious threats related to anthropic activities and the uncontrolled pets. However, the transmission of several pathogens such as parasites by domestic dogs is an important conservation issue with limited attention in Chile. The lack of a proper identification of the helminths of wild canids in the country, based mostly in coprological studies, limited our knowledge in potential interspecific transmission. Thus, the aim of the present survey was to identify the parasitic fauna of two native canids, the Andean fox (Lycalopex culpaeus) (n=49) and Chilla (Lycalopex griseus) (n=17), from several localities in Chile through a complete parasitological survey. Sixteen different species were identified, 9 of which are new host records for Andean fox and two for Chilla fox in South America, and three are recorded for first time in Chile. Also, five of them are of zoonotic concern and six are known to use domestic dogs as their principal hosts. These findings have implications for public health and the conservation of canids whose interspecific transmission of parasites with domestic dogs is confirmed through these findings. The need for an exhaustive surveillance of wild carnivores is emphasized considering these hosts as important sources of micro- and macroparasites.

EAR MITES, OTODECTES CYNOTIS, ON WILD FOXES (PSEUDALOPEX SPP.) IN CHILE

We found the ear mite parasite (Otodectes cynotis; Acari: Psoroptidae) in two distant insular endangered fox populations in Chile. We identified O. cynotis in both the Darwin's fox (Pseudalopex fulvipes) from Chiloé and the Fuegian culpeo (Pseudalopex culpaeus lycoides) in Tierra del Fuego. These populations are approximately 2,000 km apart. Infestation rates were high for both endemic foxes: 76% (19/25) of Darwin's foxes were affected, and 73% (11/15) of Fuegian culpeos had ear mites. Two Darwin's foxes had abundant ear discharge, and one of these also exhibited secondary infections of Morganella morganii and Geotrichum sp. fungi. Mites were characterized molecularly as Otodectes spp. for the Fuegian culpeo samples. Genetic analyses of two mites found the O. cynotis genotype I, as well as what appeared to be a new allele sequence for O. cynotis. These results confirmed the hypothesis of a worldwide distribution species of ear mite. Introduced chilla foxes (Pseudalopex griseus; n=11) on Tierra del Fuego Island and domestic dogs (Canis lupus familiaris; n=379) from both islands were also sampled, but they showed no signs of infection. Our findings provided insight into the genetic diversity, the origins, and the possible impact of this globally distributed mite on endemic free-ranging populations of foxes.

Underlying social attitudes towards conservation of threatened carnivores in human-dominated landscapes

AbstractCarnivore conservation depends on people's willingness to implement management practices to reduce threats to carnivores and mitigate conflicts between carnivores and domestic animals. We assessed the willingness of rural communities in central-southern Chile to (1) conserve carnivores, and (2) adopt management practices to reduce predation of domestic animals, a key factor triggering carnivore–human conflicts in rural areas. The study focused on five carnivores: the chilla Lycalopex griseus, the culpeo Lycalopex culpaeus, Darwin's fox Lycalopex fulvipes, the guiña or kodkod Leopardus guigna, and the puma Puma concolor. We found that rural communities perceived that threats towards carnivores rarely occurr in their region, contrary to the literature on this subject; people's attitudes differed depending on the carnivore; and people were willing to adopt management practices to help conserve carnivores (e.g. overnight protection of domestic animals and investment in infrastructure for henhouses and cowsheds), except leashing dogs. The willingness to conserve carnivores and adopt practices that would help do so may be associated with how these measures affect people's well-being. Although rural communities would like carnivores to be conserved, this cannot be achieved unless some pivotal practices, such as management of domestic dogs, are adopted by these communities. For successful biodiversity conservation outcomes in human-dominated landscapes, the social incentives necessary for rural communities to adopt appropriate management practices must be identified and implemented.

Assessing the natural circulation of canine vector-borne pathogens in foxes, ticks and fleas in protected areas of Argentine Patagonia with negligible dog participation.

We collected blood and/or ectoparasites from 49 South American grey foxes (Lycalopex griseus) and two Andean foxes (L. culpaeus) caught in two National Parks of southern Argentine Patagonia (Bosques Petrificados, BPNP; and Monte León, MLNP) where dogs are nearly absent (density < 0.01 dog/km2). Common ectoparasites were the flea Pulex irritans (88% prevalence) and the tick Amblyomma tigrinum (29%). Conventional PCR and sequencing of 49 blood samples, 299 fleas analysed in 78 pools, and 21 ticks revealed the presence of DNA of the following canine vector-borne pathogens: in grey foxes, Rickettsia sp. (3%), hemoplasmas (8%), including Mycoplasma haemocanis, and Hepatozoon sp. (50%); in P. irritans, Bartonella spp. (72% of flea pools from 76% of foxes), mostly B. vinsonii subsp. berkhoffii but also B. rochalimae, Anaplasmataceae (Wolbachia sp.; 60% and 54%), and M. haemocanis/haemofelis (29% and 18%); and in A. tigrinum, Hepatozoon sp. (33% of ticks in 4 of 7 foxes). No piroplasmid DNA was detected in any sample. Andean foxes were negative for all tested pathogens. Two different Hepatozoon haplotypes were detected: the most prevalent was phylogenetically associated with H. felis, and the other with H. americanum and related sequences. Amblyomma tigrinum and Hepatozoon sp. were more abundant and/or prevalent in BPNP than in colder MLNP, 300 km southwards, perhaps located close to the limit for tick suitability. Bartonella v. berkhoffii was also significantly more prevalent in fleas of foxes in BPNP than in MLNP. This study provides novel information about natural host-pathogen associations in wildlife, markedly extends the distribution area in South America of arthropods and vector-borne pathogens of veterinary and public health interest, and contributes preliminary evidence about the potential role of A. tigrinum and P. irritans as vectors, respectively, for potentially new species of Hepatozoon from Lycalopex spp. and for M. haemocanis that should be further investigated.

Serologic Survey of Brucella canis and Leptospira spp. in Free-Ranging Wild and Domestic Canids from Tierra del Fuego, Chile.

We investigated exposure to Brucella canis and Leptospira spp. in sera from 56 canids sampled between 2008 and 2012 in Tierra del Fuego, Chile. No seropositives to B. canis were found. We detected antibodies against Leptospira spp. in Fuegian culpeo fox (Pseudalopex culpaeus lycoides; 20%), chilla foxes (Pseudalopex griseus; 8%), and dogs (Canis lupus familiaris; 3%).

Diet of the South american gray fox Lycalopex griseus in an agroecosystem of southern-central Chile

Lycalopex griseus is a canid distributed in Chile and part of Argentina. Although its food habits have been extensively documented, data for anthropized environments are missing. Understanding the response of this species in these habitats is key, given the progressive modification of the landscape throughout its range. The study area is an agroecosystem of southern-central Chile. Scats were collected throughout the study area and analyzed in the laboratory. Food remains in scats were identified to species and quantified, considering the percentage of the various prey categories in terms of both relative frequency and relative biomass. Thirteen categories were found, with rodents dominating in terms of both relative frequency and percent biomass, followed by birds and arthropods. The presence of exotic species in the food spectrum is highlighted, represented by orders Lagomorpha and Rodentia. Plant material was found to a lesser extent. The diversity of preys evidences that Lycalopex griseus is mainly generalist in this type of habitat, as arboreal species were scarce in the diet, an expected finding considering the predominance of herbaceous vegetation in the study area. Lagomorphs were poorly represented compared to other latitudes, suggesting segregation with other species.

Diet, dietary selectivity and density of South American grey fox, Lycalopex griseus, in Central Chile.

The South American grey fox Lycalopex griseus is a canid widely distributed in southern South America; however, some aspects of its biology are still poorly known. We studied the diet and density of L. griseus in the Lago Peñuelas Biosphere Reserve, in Central Chile. The trophic niche breadth was B = 6.16 (Bsta = 0.47) and prey diversity was H' = 2.46 (Hmax ' = 3.17, J' = 0.78). The highest proportions of prey consumed in the diet were Oryctolagus cuniculus (52.21%) and other mammals (32.78%). We compared these results with a latitudinal gradient of diet results for this species in Chile. L. griseus eats mostly mammals (>90% of total prey), consuming the rodent Phyllotis darwini and reptiles in the northern zone; Oryctolagus cuniculus, Octodon degus and Abrocoma bennetti in the central zone; Abrothrix spp. and lagomorphs in the southern zone; and Lepus capensis and Ovis aries in the austral zone. The estimated density of L. griseus in Lago Peñuelas NR was 1.3 foxes/km2 .

Richness of plants, birds and mammals under the canopy of Ramorinoa girolae, an endemic and vulnerable desert tree species

Dominant woody vegetation in arid ecosystems supports different species of plants and animals largely dependent on the existence of these habitats for their survival. The chica (Ramorinoa girolae) is a woody leguminous tree endemic to central-western Argentina and categorized as vulnerable. We evaluated 1) richness of plants, birds and mammals associated with the habitat under its canopy, 2) whether richness is related to the morphological attributes and to the features of the habitat under its canopy, and 3) behavior displayed by birds and mammals. We recorded presence/absence of plants under the canopy of 19 trees in Ischigualasto Provincial Park. Moreover, we recorded abundance of birds and mammals and signs of mammal activity using camera traps. Our camera traps captured more than 80, 90 and 50 % of plants, birds and mammals, respectively. The coverage estimate was 83 % for birds and 89 % for mammals. Bird species richness decreased by -43 %, for every unit increase in number of stems; although richness of plants and mammals was not explained by any variable considered. Birds and mammal species invested more time in foraging than they did in moving or resting under canopies. The abundance of South American gray fox (Lycalopex griseus) increased 9 % with abundance of birds, though not with abundance of mammals. This is the first study to assess the role of R. girolae in the provision of biodiversity-related ecosystem services; a relevant aspect because their conservation can enhance biodiversity in arid ecosystems.

Management of Protected Areas and Its Effect on an Ecosystem Function: Removal of Prosopis flexuosa Seeds by Mammals in Argentinian Drylands.

The ecological function of animal seed dispersal depends on species interactions and can be affected by drivers such as the management interventions applied to protected areas. This study was conducted in two protected areas in the Monte Desert: a fenced reserve with grazing exclusion and absence of large native mammals (the Man and Biosphere Ñacuñán Reserve; FR) and an unfenced reserve with low densities of large native and domestic animals (Ischigualasto Park; UFR). The study focuses on Prosopis flexuosa seed removal by different functional mammal groups: “seed predators”, “scatter-hoarders”, and “opportunistic frugivores”. Under both interventions, the relative contribution to seed removal by different functional mammal groups was assessed, as well as how these groups respond to habitat heterogeneity (i.e. vegetation structure) at different spatial scales. Camera traps were used to identify mammal species removing P. flexuosa seeds and to quantify seed removal; remote sensing data helped analyze habitat heterogeneity. In the FR, the major fruit removers were a seed predator (Graomys griseoflavus) and a scatter-hoarder (Microcavia asutralis). In the UFR, the main seed removers were the opportunistic frugivores (Lycalopex griseus and Dolichotis patagonum), who removed more seeds than the seed predator in the FR. The FR shows higher habitat homogeneity than the UFR, and functional groups respond differently to habitat heterogeneity at different spatial scales. In the FR, because large herbivores are locally extinct (e.g. Lama guanicoe) and domestic herbivores are excluded, important functions of large herbivores are missing, such as the maintenance of habitat heterogeneity, which provides habitats for medium-sized opportunistic frugivores with consequent improvement of quality and quantity of seed dispersal services. In the UFR, with low densities of large herbivores, probably one important ecosystem function this group performs is to increase habitat heterogeneity, allowing for the activity of medium-sized mammals who, behaving as opportunistic frugivores, did the most significant seed removal.

Fleas and Ticks in Carnivores From a Domestic-Wildlife Interface: Implications for Public Health and Wildlife.

Fleas and ticks are parasites of wild and domestic mammals, and can be vectors of several pathogens. In rural areas, domestic carnivores such as the domestic dog (Canis lupus familiaris L.), may act as a "bridge" between natural areas and human settlements where ectoparasites can be used as a metric of such link. The aim of this study was to identify fleas, ticks, and Rickettsia spp., collected from domestic and wild carnivores in a natural reserve and surrounding human settlements in Central Chile, using morphological keys and molecular analysis. We surveyed 170 households from which 107 dogs and eight cats were sampled. From the natural reserve, we sampled two chilla foxes (Pseudalopex griseus Gray), two lesser grison (Galictis cuja Molina), three kodkods (Leopardus guigna Molina), and four dogs. From dogs, we collected Ctenocephalides felis Bouché, Ctenocephalides canis Curtis, Pulex irritans L., and Rhipicephalus sanguineus s.l. Latreille; C. felis was the most frequent ectoparasite. Cats were infested only by C. felis and Rh. sanguineus s.l. From wild carnivores, we obtained C. canis and P. irritans, the latter being most frequent. Molecular analysis of P. irritans detected 10 haplotypes and two main clades, which tended to separate fleas from wild and domestic hosts. Molecular analysis of ompA and ompB genes confirmed the presence of Rickettsia felis in fleas collected from owned dogs and cats, which could represent a potential risk factor of R. felis transmission in the area.

Detection of Leishmania DNA in wild foxes and associated ticks in Patagonia, Argentina, 2000 km south of its known distribution area.

BackgroundZoonotic Visceral Leishmaniasis (ZVL) is a vector-borne disease affecting humans and other mammals and caused by the protozoan parasite Leishmania (Leishmania) infantum (syn. L. chagasi), belonging to the L. donovani complex. The regions in Northern Argentina (above 32 °S) are its southern distribution limit in South America.ResultsWe detected Leishmania sp. DNA (most likely belonging to the L. donovani complex) in 37.5 % of 32 grey foxes (Pseudalopex griseus) captured in Argentinean Patagonia (48°S and 50°S). Eleven monosexual pools of Amblyomma tigrinum ticks from eight different foxes (six grey foxes and two culpeo foxes P. culpaeus) were also positive. The southernmost known distribution limit for L. infantum, and the southernmost reported capture of a phlebotominae, had previously been 2000 and 750 km north of our study area, respectively.ConclusionsThis finding is significant because it markedly extends the distribution area of leishmaniasis; supports the existence of a sylvatic cycle in the absence of dogs; and has implications in transmission, indicating that either sand fly distribution is broader than currently thought or non-sand fly Leishmania maintenance is possible. Additional molecular, parasitological, epidemiological and entomological studies are still needed.

Almacenadores y frugívoros oportunistas: el papel de los mamíferos en la dispersión del algarrobo (Prosopis flexuosa DC) en el desierto del Monte, Argentina

Campos, C.M., Velez, S. 2015. Opportunistic scatter hoarders and frugivores: the role of mammals in dispersing Prosopis flexuosa in the Monte desert, Argentina . Ecosistemas 24(3): 28-34. Doi.: 10.7818/ECOS.2015.24-3.05 Prosopis flexuosa woodlands provide multiple goods and services. Currently, they are undergoing a strong retraction as a result of a historical extractive use; hence it becomes urgent to promote the conservation and sustainable management of these woodlands as a system. The objective of this study is synthesizing the knowledge of mutualistic and antagonistic interactions between mammals and Prosopis fruits and seeds, particularly considering opportunistic animals that consume fruits: scatter hoarders and frugivores. Small rodents (such as Eligmodontia typus and Microcavia australis ) are potential seed dispersers because they predate on a few seeds and store the rest in caches on the ground surface. Opportunistic frugivores, like wild mammals ( Dolichotis patagonum, Lepus europaeus, Lycalopex griseus, Lama guanicoe, etc.), and domestic mammals (donkey, horse, cow) disperse seeds by endozoochory, affording benefits such as transport of huge numbers of seed, removal of the barriers maintaining dormancy and disinfection of insect-attacked seeds. However, endozoochory brings costs to the viability and germination capacity of seeds, depending on the disperser involved. In a scenario of continuous land use changes and global climate change, knowledge of the diverse array of animals that benefit dispersal provides scientific grounds for considering that the biodiversity associated with woodlands must be included in their management and conservation.

Native forest replacement by exotic plantations triggers changes in prey selection of mesocarnivores

ABSTRACT Replacement of native forests by forest plantations may change the composition and abundance of small mammals, thus influencing the foraging behavior of mesocarnivores in these human-created habitats. We assessed how differences in prey abundance between native forests and exotic plantations in southern Chile may explain the prey selection of four mesocarnivores, as analyzed from their scats. Using a spatial zero-inflated Poisson model, we determined that the abundance of most small mammals was lower in plantations than native forests, except for three common species, which had similar or larger abundances in exotic plantations. We assessed mesocarnivores' prey selection by assessing the coefficients and log-ratios of use and availability of a Bayesian Resource Selection Function. We determined that in native forest, the preferences of kodkod ( Leopardus guigna ) for arboreal prey was stronger, whereas chilla fox ( Pseudalopex griseus ) and Darwin's fox ( Pseudalopex fulvipes ) exhibited a selective preference for ground prey. Darwin's fox also exhibited a habitat-dependent changes in their selection for Darwin's leaf-eared mouse ( Phyllotis darwini ), from a positive log ratio in native forest to a negative ratio in exotic plantations. Conversely, culpeo fox ( Pseudalopex culpaeus ) selected long-tailed colilargo ( Oligoryzomys longicaudatus ) and Chilean climbing mouse ( Irenomys tarsalis ) in plantations only, even though these prey were more abundant in native forests. Although mature commercial forest plantations may provide feeding grounds for mesocarnivores, depending on their species-specific ability to capture available prey, the decline of small mammal availability in plantations may modify the prey selection of mesocarnivores.

Diurnal Human Activity and Introduced Species Affect Occurrence of Carnivores in a Human-Dominated Landscape.

Diurnal human activity and domestic dogs in agro-forestry mosaics should theoretically modify the diurnal habitat use patterns of native carnivores, with these effects being scale-dependent. We combined intensive camera trapping data with Bayesian occurrence probability models to evaluate both diurnal and nocturnal patterns of space use by carnivores in a mosaic of land-use types in southern Chile. A total of eight carnivores species were recorded, including human-introduced dogs. During the day the most frequently detected species were the culpeo fox and the cougar. Conversely, during the night, the kodkod and chilla fox were the most detected species. The best supported models showed that native carnivores responded differently to landscape attributes and dogs depending on both the time of day as well as the spatial scale of landscape attributes. The positive effect of native forest cover at 250m and 500 m radius buffers was stronger during the night for the Darwin's fox and cougar. Road density at 250m scale negatively affected the diurnal occurrence of Darwin´s fox, whereas at 500m scale roads had a stronger negative effect on the diurnal occurrence of Darwin´s foxes and cougars. A positive effect of road density on dog occurrence was evidenced during both night and day. Patch size had a positive effect on cougar occurrence during night whereas it affected negatively the occurrence of culpeo foxes and skunks during day. Dog occurrence had a negative effect on Darwin's fox occurrence during day-time and night-time, whereas its negative effect on the occurrence of cougar was evidenced only during day-time. Carnivore occurrences were not influenced by the proximity to a conservation area. Our results provided support for the hypothesis that diurnal changes to carnivore occurrence were associated with human and dog activity. Landscape planning in our study area should be focused in reducing both the levels of diurnal human activity in native forest remnants and the dispersion rates of dogs into these habitats.

Conditioned taste aversion in the grey fox (Pseudalopex griseus), in Southern Argentine Patagonia

Attempts to control cougar (Puma concolor) and culpeo fox (Pseudalopex culpaeus) populations in Patagonia through poisoning, negatively affects grey foxes (Pseudalopex griseus) and many other non-target species. It is therefore advisable to develop selective predator control methods. Among a wide range of potential methods, are those based on manipulating the behaviour of non-target species. Conditioned taste aversion (CTA) develops when an animal associates taste with subsequent illness, and, after recovery, avoids the referent taste. Food aversions can be potentially useful in efforts to reduce losses of non-target species when lethal baits are distributed to control other predators. We evaluated two ways to add the aversion agent Levamisole hydrochloride to a bait to generate CTA in grey foxes. We established one control (without Levamisole) and two treatments: plain Levamisole and an ion-exchange resin complex (resinate: Amberlite® IRP-64) aiming to mask the taste of Levamisole. Foxes that ate plain Levamisole baits, ate fewer baits than those in control (26.7% plain Levamisole baits vs. 83.3% untreated baits, P=0.002) even after plain Levamisole was no longer present in the baits (40.0% vs. 86.6% untreated baits, treatment and control respectively, P=0.007). Foxes that ate Levamisole resinate baits, also ate fewer baits than those in control (50.0% Levamisole resinate baits vs. 83.3% untreated baits, P=0.043) but then resumed consumption when baits no longer contained the Levamisole resinate (73.3% vs. 86.6% untreated baits, treatment and control respectively, P=0.329). Thus, foxes that failed to detect the plain Levamisole in baits acquired CTA to the bait. Contrary to our expectations, foxes detected the Levamisole resinate, associated illness with it and so resumed eating baits as soon as the resinate was withdrawn. Additionally, in the control, where foxes were familiar with untreated “safe” baits, we repeated the treatment with Levamisole resinate baits to test latent inhibition (decrement in conditioning to a stimulus as a result of its prior exposure). We found that treated bait consumption did not decrease as before, during a similar number of days (76.6% Levamisole resinate baits vs. 83.3% untreated baits, P=0.631), suggesting that latent inhibition prevented development of CTA within our experimental time period. CTA induced among grey foxes that consume plain Levamisole baits might spare them from being poisoned in attempts to control other species of predators.

Estado del zorro gris &lt;em&gt;Lycalopex griseus&lt;/em&gt; (Gray, 1837) (Mammalia: Canidae) en el Perú

Se sustenta la presencia del zorro gris Lycalopex griseus (Gray, 1837) en la costa sur del Perú en base a información morfológica externa y craneal. Esta especie es de similar tamaño a L. sechurae (Thomas, 1900) pero diferenciable en una mayor longitud del hocico y menor amplitud del cráneo; esta diferencia es respaldada en un Análisis de Componentes Principales. Se sugiere que la población del zorro gris en el Perú podría constituir una subespecie nueva de L. griseus por encontrarse más al norte de su distribución tradicionalmente conocida y separada de otras subespecies por el Desierto de Atacama en el norte de Chile, notable barrera biogeográfica.