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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&ndash, 23%, whereas the grey fox and puma populations increased at an average annual rate of 7% and 19%, respectively. The grey fox&rsquo, 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.

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. Fil: Nielsen, Sigrid. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Travaini, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Vassallo, Aldo Iván. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Procopio, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Zapata, Sonia Cristina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina

We searched for correspondence between morphol- ogy and trophic habits in an assemblage of six species of coexisting carnivoransfromPatagoniatoconfirmthepredictive powerof the studyof the trophic morphologyas anapproachto the study of resource partitioning, which is often utilized in paleontological studies. The six species were assigned to four morphoguilds and to four trophic guilds, although the species composition of both spaces was only coincident during one of the twostudied time periods. Themost obvious explanationfor this lack of correspondence is based on the assumption that species can change from one ecological guild to another, while their relative positions in the morphospace will befixed. There- fore, the observed lack of correspondence could be searched in the contextof differences betweenthe ecologicalandevolution- ary scales. Althoughmorphological specialization toward some type of diet has been corroborated in our assemblage, the inference of interactions in ecological time amongspecies from the past fromits morphology must be considered with caution

The summer diet of the Patagonian opossum Lestodelphys halli was studied in southern Argentinean Patagonia. Faeces of opossums captured alive and stomach contents from dead animals were collected and analyzed. A wide variety of invertebrates (87.2% frequency of occurrence) followed by birds and reptiles (10.64%) occurred both in faeces and stomachs, and fruits were occasionally consumed. Although the Patagonian opossum was reported as a carnivorous species in captivity, feeding mainly on rodents, reptiles, birds and invertebrates, we did not find remains of rodents in the diet of the opossums. We suggest that Patagonian opossums are not an efficient rodent predator in the wild. The high consumption of invertebrates, reptiles, birds and fruits during the warm season when these items are abundant reflects the opportunistic behavior of this species. Estudiamos la dieta estival de la comadrejita patagónica Lestodelphys halli en el sureste de la Patagonia Argentina, por medio del análisis de contenidos estomacales provenientes de animales muertos y de fecas. Encontramos una gran variedad de invertebrados (87,2% de frecuencia de ocurrencia) seguido de aves y reptiles (10,64%) tanto en estómagos como en fecas. Los frutos fueron escasos en la dieta. En cautividad, la comadrejita patagónica se alimenta fundamentalmente de roedores, reptiles, aves e invertebrados. Sin embargo, no encontramos restos de roedores en la dieta de la comadrejita. Sugerimos que la comadrejita patagónica no es un predador eficiente de roedores en estado silvestre. El alto consumo de invertebrados, reptiles, aves y frutos durante el verano, cuando estos ítems son abundantes, refleja el comportamiento oportunista de esta especie. Fil: Zapata, Sonia Cristina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Procopio, Diego Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Travaini, Alejandro. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rodríguez, Alejandro. Consejo Superior de Investigaciones Científicas. Estación Biológica de Doñana; España

Although Tadarida brasiliensis is one of the most widely distributed species of bats in Argentina, it is nevertheless extremely scarce in Patagonia. We report a second record of T. brasiliensis for Santa Cruz province, which fills a gap in the geographical distribution of this species in that province and is also the third southernmost record for the species and for any molossid bat in the world. Fil: Zapata, Sonia Cristina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Procopio, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Morgenthaler, Annick. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Travaini, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina

There is evidence for the ecological extinction of the native prey of the puma Puma concolor in north-western Argentine Patagonia. In this study we examine whether this is also the case in southern Patagonia. From 2004 to 2007 we examined the puma's diet in three protected areas and two sheep ranches in Santa Cruz province. A total of 282 puma scats were analysed. In two of the protected areas and in the ranches 60-74% of the puma's diet was native prey. Prey species were primarily guanaco Lama guanicoe, followed by Patagonian mara Dolichotis patagonum, lesser rhea Pterocnemia pennata pennata, Patagonian pichi Zaedyus pichiy and Magellanic penguin Spheniscus magellanicus. In the third protected area the main prey was the European hare Lepus europaeus. Our results show a clear difference in the diet of the puma in southern compared to north-western Patagonia. Large native herbivores (i.e. guanaco and lesser rhea) maintain their role as the main prey species for the puma in southern Patagonia. We suggest, therefore, that native prey could be restored to those areas of Argentine Patagonia, such as the north-west, where they are currently ecologically extinct. Facilitating native species recovery and/or restoration and applying more rigorous controls to prevent the introduction of potential alien prey species of the puma both, within and outside protected areas, needs to be evaluated as a regional strategy. Fil: Zanón Martínez, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Travaini, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Zapata, Sonia Cristina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Procopio, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina Fil: Santillán, Miguel Ángel. Universidad Nacional de La Pampa. Facultad de Ciencia Exactas y Naturales. Departamento de Recursos Naturales. Centro para el Estudio y Conservación de Aves Rapaces; Argentina

The Lesser Rhea (Rhea pennata pennata) has suffered a marked decline in numbers over recent decades, probably mainly as a result of livestock production and overhunting. Our aim was to investigate the factors that determine the distribution of Lesser Rheas in southern Patagonia and to generate a predictive regional distribution map. We surveyed 8000 km of roads and sighted 795 Lesser Rhea individuals or flocks. We also estimated environmental predictors from remotely sensed data and analysed the occurrence of Lesser Rheas in relation to these predictors. The predictors we examined were associated with four hypotheses explaining the distribution of Lesser Rheas: the persecution by ranchers, primary productivity, topography, and anthropogenic disturbance hypotheses. We built models for each hypothesis. Our results suggest that the distribution of Lesser Rheas is not negatively affected by persecution by ranchers, as the species is more abundant in areas with high stocking levels of sheep, but is positively influenced by primary productivity and negatively by the proximity of human habitation. The resulting distribution map can be used as a management tool for government agencies and highlights the conservation priorities for managing this declining and emblematic species.

Culpeo fox (Pseudalopex culpaeus) and gray fox (Pseudalopex griseus) are heavily culled in Patagonia. Fox populations seem to persist thanks to spatial refuges from which hunted areas are repopulated, following a source– sink dynamics. Sustainable use of Patagonian foxes warrants the design of a monitoring program in nature reserves and areas subjected to predator control. During 7 years, we used visitation indices to bait stations in a national park and neighboring sheep ranches of southern Argentina. We operated bait stations during three consec- utive nights and calculated seven indices of relative abundance. For each fox species, we compared the power of different monitoring designs and scenarios that combined visitation indices, effort (number of bait station lines and survey frequency) while controlling for type I error, and magnitude of population change during a given period. We looked at the combinations that produced high power (β ≤ 0.24). The operation of bait stations during several nights markedly increased statistical power. Index 7 (recording visits 72 h after activation) exhibited the lowest variation and improved expected power to detect a population trend. Both fox species could be monitored simultaneously, with power >0.76 in the short term (5 years), activating 24 bait station lines. We conclude that monitoring programs for culpeo fox and gray fox based on bait stations are able to detect marked declines but are less useful to reliably detect moderate increases in abundance, especially in sheep ranches.

Presentamos el primer análisis cuantitativo de la dieta de Falco sparverius en el sur de Argentina. Identificamos 1169 ítems de presas en un total de 272 egagrópilas y siete restos de presas de cuatro sitios de estudio en la Patagonia. En esta área, F. sparverius se alimentó principalmente de escorpiones (Bothruridae), escarabajos (Coleoptera), hormigas (Formicidae), saltamontes (Acrididae), gorgojos (Curculionidae) y roedores (Rodentia). La dieta difirió significativamente entre los sitios de estudio en términos de la frecuencia de varios ítems entre las presas, pero no en términos de la biomasa. De acuerdo a la frecuencia, los insectos conformaron la mayor parte de la dieta en la mayoría de los sitios, pero los vertebrados contribuyeron más en términos de biomasa.

In this paper we show how new technologies can be incorporated from the gathering of field data on wildlife distribution to the final stage of producing distribution maps. We describe an integrated framework for conducting wildlife censuses to obtain data to build predictive models of species distribution that when integrated in a GIS will produce a distribution map. Field data can be obtained with greater accuracy and at lower costs using a combination of Global Positioning System, Personal Digital Assistant, and specific wildlife recording software. Sampling design benefits from previous knowledge of environmental variability that can be obtained from free remote sensing data. Environmental predictors derived from this remote sensing information alone, combined with automatic procedures for predictor selection and model fitting, can render cost-effective predictive distribution models for wildlife. We show an example with guanaco distribution in the Patagonian steppes of Santa Cruz province, Argentina.

We describe a new species within the genus Liolaemus from southeast Argentine Patagonia. This new taxon, Liolaemus yatel sp. nov., presents anatomical traits shared with the Liolaemus lineomaculatus section within the Liolaemus lineomaculatus group, especially the absence of precloacal pores in both sexes. However, Liolaemus yatel sp. nov. does not exhibit trifid dorsal scales, which is a diagnostic character of the L. lineomaculatus group. Moreover, this new species differs from other taxa of the L. lineomaculatus group in that dorsal and nuchal scales either completely lack keels or are slightly keeled. We also report, for the first time, the presence of trifid scales in Liolaemus magellanicus, another species included in the L. lineomaculatus section but constituting an independent lineage regarding the L. lineomaculatus group. The phenotypic traits of L. yatel sp. nov. and the presence of trifid scales in L. magellanicus provide additional information for the study of evolutionary relationships among the species of the L. lineomaculatus section, especially the establishment of their diagnostic character states.