Pablo F. Gregorio

National Scientific and Technical Research Council | conicet · INIBIOMA Instituto de Investigaciones en Biodiversidad y Medio Ambiente

Spatial subsidies of nutrients within and among ecosystems have profound effects on ecosystem structure and functioning. Large animals can be important drivers of nutrient cycling and transport as they ingest resources in some habitats and release them in others, even moving nutrients against elevational gradients. In high Andean deserts, vicuñas (...

The taxonomy and phylogeny of this species have been the subject of several published studies, including the use of genetic and genomic tools, which has allowed new advances in this topic. This chapter presents a summary of the names by which this species was called by the different cultures that lived in close relationship with the guanaco. Then,...

Desertification is the most important social, economic, and ecological problem in Patagonia. Several factors have contributed to the ecosystem impoverishment: inadequate use of natural grasslands; lack of training and advisory services for producers; scarce transference of management technologies adapted for arid areas; low value of primary product...

Resumen El uso sostenible de especies animales de la fauna silvestre requiere de lineamientos claros y orientados hacia a los criterios de bienestar animal. En este trabajo, se brindan una serie de pautas para las prácticas de manejo de poblaciones de guanacos silvestres, que surgen de los estudios científicos realizados desde el año 2000. Se descr...

The factors that regulate the abundance and distribution of wild herbivores are key components of a species’ ecology and include bottom-up and top-down mechanisms, as well as aspects related to social organization. In territorial ungulates, males distribute themselves to enhance access to females by anticipating how resources will influence female...

Ref.: Can. J. Zool. 98(1): 13–20 (2020) dx.doi.org/10.1139/cjz-2019-0070. The corrections are typographic in nature and do not affect the results or the discussion of the research.

Aggression is a social behaviour which can be affected by numerous factors. The quality and quantity of food resources may play an important role in the aggressiveness of territorial ungulates as the defence of these resources influences female choice and mating opportunities. However, the relationship between food resources and aggression remains...

Intraspecific variation in mating behavior has been documented in diverse taxa, including ungulates. Here, we report and describe for the first time the existence of alternative mating tactics in a wild guanaco (Lama guanicoe) partially migratory population. We document (1) a resource-defense tactic, widely reported for different populations; and (...

Si bien hubo una drástica reducción poblacional del guanaco en Argentina, estimada entre el 90 y 97% desde la colonización europea, la tendencia de los últimos 30 años fue en aumento (González & Acebes 2016). Actualmente, la población total estimada para Argentina es de un poco menos de un millón de guanacos (González & Acebes 2016) y la amplitud e...

El equilibrio entre la energía requerida para satisfacer las funciones vitales y la energía que se obtiene de la dieta representa un aspecto fundamental para comprender los atributos adaptativos de una especie a su ambiente. Nuestro objetivo fue evaluar la incidencia de la calidad de la dieta sobre los mediadores fisiológicos de la movilización ene...

Pregnancy status is usually not included in ecological studies due to the difficulty of its evaluation. The use of non-invasive methods is an opportunity to incorporate pregnancy on population studies as can be used avoiding physical restraint of the individuals. In this study, we evaluated sex steroid hormones in plasma and fecal samples on pregna...

In adaptive terms, animals are subject to challenges imposed by their environment. To address physiological patterns in wild mammals, the non‐invasive study of glucocorticoid hormones has become the main approach through two well‐defined conceptual frameworks: one is related to stress responses, whereas another refers to the glucocorticoids as phys...

The wild boar (Sus scrofa) is an invasive species and currently considered as one of the most dangerous species around the world. Although its negative impacts on ecosystems have been broadly described, little is known about its patterns of habitat use in protected areas of South America. In this study, we assessed macro and microhabitat patterns o...

A considerable increase in creatinine kinase (CK) activity and gastrin hormone due to exercise has been observed in sled dogs during endurance mushing races; however, there have been no studies on sled dogs during recreational mushing. Although oxytocin hormone is involved in social behaviors and empathy, it has not been studied in sled dogs. This...

Diet quality of wild guanacos and its influence on physiological indicators of energetic demand The guanaco (Lama guanicoe) is the dominant native herbivore of the arid lands in Argentina. It is a species with numerous anatomical-physiological features of great adaptive value that allow it to inhabit hostile zones in terms of its environmental feat...

In certain areas of South America, free-ranging, wild guanacos (Lama guanicoe) are exploited for fibre by local people. This activity includes the capture and handling of animals which can adversely affect their behaviour and physiology. This study investigated the behavioural and physiological responses of guanacos to shearing and handling activit...

The gastrointestinal parasite community of wild guanacos (Lama guanicoe) from La Payunia Provincial Reserve, Mendoza, Argentina. The parasite community of wild vertebrate hosts is composed of several species, but the natural structure of these communities is currently being affected by habitat fragmentation and the introduction of exotic species. T...

The parasite community of wild vertebrate hosts is composed of several species, but the natural structure of these communities is currently being affected by habitat fragmentation and the introduction of exotic species. The aim of this work was to identify, through the recognition of immature stages in feces, the gastrointestinal parasite species p...

Animals optimize the trade-off between the cost of not fleeing and the benefits of staying because the factors that influence flight decisions and the disturbance level of a particular stimulus can vary both spatially and temporally. Different factors (human impact and habitat characteristics) likely to modify anti-predator behaviour in different t...

Animals optimize the trade-off between the cost of not fleeing and the benefits of staying because the factors that influence flight decisions and the disturbance level of a particular stimulus can vary both spatially and temporally. Different factors (human impact and habitat characteristics) likely to modify anti-predator behaviour in different t...

Monitoring species abundance and distribution is a prerequisite when assessing species status and population viability, a difficult task to achieve for large herbivores at ecologically meaningful scales. Co-occurrence patterns can be used to infer mechanisms of community organization (such as biotic interactions), although it has been traditionally...

Live-shearing of wild guanacos Lama guanicoe may affect their reproductive success and population resilience, and therefore it is important to assess the biological sustainability of obtaining their wool. We evaluated effects of capture and shearing on survival and reproduction, population parameters, daily movements, ranging behaviour and spatial...

Habitat can constrain and shape successful ecological and physiological strategies, thus providing the context for the evolution of life-history traits. However, unpredictable challenges, such as storms, natural disasters, and human activities can also have great effects on stress. Glucocorticoids (GCs) are adrenal steroid hormones that play an imp...

Species occurrence depends on both environmental and biotic factors (species interactions). Consideration of species interactions when estimating functions of population distribution is unusual, and may be crucial to understand and predict how species use space and resources. In this study, we combine resource selection probability functions (RSPFs...

The concept of sociality has been associated with the effectiveness of antipredator mechanisms, like cooperative vigilance and the dilution effect. Lama guanicoe (guanaco) is a social native herbivore in South America and a social species. The objectives of this study were to evaluate the antipredator responses of different-sized groups of guanacos...

Both ethology and physiology can provide insights about stress conditions in wild animals during handling. Lama guanicoe (guanaco) is the major large herbivore inhabiting arid zones in Argentina. Since 2005, the Payún Matrú Cooperative, a business established and run by native people, has captured and handled guanacos for shearing at Payunia Reserv...