Monitoring vultures in the 21st century: The need for standardized protocols

This article calls on scientists, managers and organizations focused on vulture conservation to promote and use standardized monitoring programs based on sampling of molted feathers.Fil: Perrig, Paula Leticia. University of Wisconsin; Estados UnidosFil: Lambertucci, Sergio Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Donadio, Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Padro, Julian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. University of Wisconsin; Estados UnidosFil: Pauli, Jonathan Nicholas. University of Wisconsin; Estados Unido

More than just meat: Carcass decomposition shapes trophic identities in a terrestrial vertebrate

Most food web models fail to account for the full complexity of interactions within a community, particularly where microbes are involved. Carcasses are microbe-rich resources and may represent a common nexus for the macrobiome and microbiome, effectively uniting autotrophs, consumers, predators and microbiota. We evaluated the role of carcasses as multitrophic resources and explored dietary partitioning for a sexually dimorphic obligate scavenger known for its hierarchical social system. This study was set in a well-studied community of camelids Vicugna, Lama guanicoe, pumas Puma concolor and Andean condors Vultur gryphus in the Andes. We hypothesized that condors, by feeding on trophically distinct dietary substrates within any given carcass, would have highly variable trophic position (TP) values. Furthermore, we expected that the microbial consumers within the carcass would inflate TP values in both, the carrion and the condors. Thus, we expected that the trophic heterogeneity within a carcass could facilitate sex-based dietary partitioning in condors. We used a multifaceted approach to assess the foraging of Andean condors, using regurgitated pellet and bulk isotopic analyses, and also quantified the TP of the entire community of graminoids, camelids, camelid carrion, pumas, and female and male condors employing compound-specific stable isotopes analysis of amino acids. Our analysis of condor pellets and bulk isotopes revealed non-trivial plant consumption, close to 10% of condor diet. Isotope analysis of amino acids revealed that condors had highly variable TPs (2.9 ± 0.3) compared to pumas (3.0 ± 0.0) and camelids (2.0 ± 0.1), likely representing ‘trophic omnivory’, wherein the condors consume plants (TP = 1.0 ± 0.1) and microbe-colonized carrion (2.3 ± 0.1). Female condors exhibited a TP (2.8 ± 0.2) lower than strict carnivory, suggesting that they consume more plant biomass in a carcass, while males (TP = 3.1 ± 0.3) are likely consuming more of the microbe-rich animal tissue. Our study highlights that carcasses represent a trophically heterogeneous resource and that vertebrate scavengers can feed across trophic groups within the carcass, from autotrophs to secondary consumers, and from both the macrobiome and microbiome. Thus, integration of microbes in macroecological contexts can help to resolve trophic identity, and better characterize the importance of microbes in detritivorous and omnivorous species. Read the free Plain Language Summary for this article on the Journal blog.Fil: Barceló, Gonzalo. University of Wisconsin; Estados UnidosFil: Perrig, Paula Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. University of Wisconsin; Estados UnidosFil: Dharampal, Prarthana. University of Wisconsin; Estados UnidosFil: Donadio, Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fundación Rewilding Argentina; ArgentinaFil: Steffan, Shawn A.. United States Department of Agriculture. Agriculture Research Service; Estados Unidos. University of Wisconsin; Estados UnidosFil: Pauli, Jonathan Nicholas. University of Wisconsin; Estados Unido

Capturing and radio ear-tagging neonatal vicuñas

We used and evaluated the effectiveness of a hand-capture technique to capture and mark neonatal vicuñas (Vicugna vicugna) at San Guillermo National Park, west-central Argentina. We captured and marked 98 neonates during 5-31 January, 2008-2010. Capture success was 92% (106 attempts), with stationary marking teams being 2.5 times as successful in detecting and capturing neonates as mobile ones. Of neonates captured, 99% were 20 minutes old typically were too mobile to capture. Sex ratio at capture was biased toward males (1.5:1), while mean body weight and neck circumference were similar between sexes. Generally, mothers remained in sight during, and immediately reunited with their neonates after, capture. Four percent of the mothers ran out of sight but then returned, while 2% failed to return. Capture-related mortality was 5%, with maternal abandonment in response to capture activities (n = 3) the leading cause. Ear-tag transmitter had minimal effects on subsequent ear position. The success of our technique likely was based on terrain (flat) and vegetative conditions (short grass), high densities of animals for monitoring (particularly in a meadow), and a predictable, pulsed birth season. This hand-capturing method was efficient for handling and marking neonatal vicuñas. Combined with the use of ear-tag transmitters, it allows the study of important perinatal processes, including movement and mortality.Facultad de Ciencias Naturales y Muse

Capybara responses to varying levels of predation risk

Predators can generate physiological and behavioural responses in prey individuals. Thus, carnivore reintroductions might cause profound changes in communities and ecosystems by modifying antipredator responses. Combining observational and experimental approaches, we compared the short- and long-term antipredator responses of capybaras, Hydrochoerus hydrochaeris, between a landscape with a high density of predators (Pantanal, Brazil) and a landscape where predators became extinct in the mid-20th century but where a jaguar reintroduction project was in progress (Iberá, Argentina). Generalized linear models were used to test whether the presence of natural predators affects capybara behavioural budgets, gregarious behaviour and the associated physiological stress responses and to test whether, in the short term, capybaras increase their vigilance levels after detecting the proximity of a simulated predator (a playback of jaguar, Panthera onca, calls). Capybaras in the Pantanal did not show higher levels of vigilance but they spent a greater proportion of time foraging than did capybaras in Iberá. Pantanal groups were smaller and foraged closer to water. The baseline levels of stress hormones tended to be higher in Iberá. In response to simulated stimuli, both populations responded to predator sound cues by increasing vigilance, but Iberá groups also increased vigilance in response to a control sound, suggesting that they did not recognize the predator stimulus as a greater risk than another stimulus. In areas with predators, capybaras may reduce predation risk by choosing safer areas, where they can spend more time foraging when predators are not nearby. Vigilance may be only a reactive response to cues of the predator's proximity. Understanding the capybara's antipredator responses may help predict the potential effects and the success of jaguar reintroduction in a region where the jaguar has been absent for over 80 years.Fil: Avila, Ana Belen. Centro de Investigaciones del Bosque Atlántico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; ArgentinaFil: Corriale, Maria Jose. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Donadio, Emiliano. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina. Fundacion Rewilding Argentina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Di Bitetti, Mario Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; Argentina. Centro de Investigaciones del Bosque Atlántico; ArgentinaFil: Ponzio, Marina Flavia. Universidad Nacional de Córdoba. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Cantarelli, Verónica Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina; ArgentinaFil: de Angelo, Carlos Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; Argentina. Centro de Investigaciones del Bosque Atlántico; Argentin

Linking predation risk, ungulate antipredator responses, and patterns of vegetation in the high Andes

Whether large carnivores indirectly influence vegetation via prey behavior remains controversial because available evidence is largely correlational, and recent field experiments have found weak associations between risk experienced by prey and vegetative responses to herbivory. We combined observational data and a field experiment to test whether an ambush predator—the puma ( Puma concolor )—affected the antipredator behavior of its primary ungulate prey—the vicuña ( Vicugna vicugna )—which in turn had cascading effects on vegetation. We predicted that strong protective effects of pumas on vegetation would be most apparent in habitats where cover and terrain (i.e., physical complexity) facilitated the ambushing strategy of pumas. In 3 different habitats, we evaluated the relationships among predation risk, vicuña behavior, and—by deploying vicuña exclosures—vegetation structure and productivity. We also examined habitat-specific rates of vegetative regrowth. Risky habitats presented high physical complexity, a disproportionately large number of vicuñas killed by pumas, and high relative abundance of pumas. In these habitats, vicuñas displayed strong antipredator behaviors and exclosures did not affect vegetation, suggesting that pumas indirectly protected plants. Conversely, a safe habitat presented low structural complexity, a disproportionately low number of vicuñas killed by pumas, and low relative abundance of pumas. Here, vicuñas relaxed antipredator behaviors and exclosures had strong effects on vegetation. In 1 habitat deemed as risky, however, cascading effects were offset likely because water and nutrients were readily available to plants and regrowth was rapid. Our results show that large ambush carnivores can positively affect vegetation via nonconsumptive effects on their prey, and that these effects are habitat mediated. However, primary productivity modulated the strength of such effects, with high primary productivity dampening the observed cascading effects.Si los grandes carnívoros terrestres afectan indirectamente la vegetación vía cambios en el comportamiento de sus presas es controversial porque la evidencia existente es largamente correlacional, y experimentos de campo recientes encontraron una débil asociación entre el riesgo de depredación y las respuestas de la vegetación a la presión de pastoreo. En este trabajo evaluamos si un depredador de emboscada—el puma ( Puma concolor )—afecta las respuestas antidepredador de su presa principal—la vicuña ( Vicugna vicugna )—con efectos de cascada sobre la vegetación (i.e., graminoides). Predijimos que el efecto protectivo de los pumas sobre la vegetación sería más evidente en hábitats donde la cobertura y el terreno (i.e., complejidad estructural) facilitan la estrategia de emboscada del puma. En tres hábitats diferentes, evaluamos las relaciones entre el riesgo de depredación, el comportamiento de las vicuñas y—mediante la utilización de clausuras—la estructura y productividad de la vegetación. También examinamos tasas de rebrote en cada hábitat. Los hábitats riesgosos presentaron gran complejidad estructural, un número desproporcionadamente alto de vicuñas depredadas por pumas, y una alta abundancia relativa de pumas. En estos hábitats, las vicuñas mostraron fuertes comportamientos antidepredador y las clausuras afectaron levemente la vegetación, sugiriendo que los pumas indirectamente protegen las plantas. Contrariamente, el hábitat definido como seguro presentó poca complejidad estructural, un número desproporcionadamente bajo de vicuñas depredadas por pumas, y una baja abundancia relativa de pumas. Aquí, las vicuñas relajaron sus comportamientos antidepredador y las clausuras tuvieron un fuerte efecto sobre la vegetación. Sin embargo, en un hábitat definido como riesgoso los efectos de cascada fueron neutralizados, probablemente porque el agua y los nutrientes estaban disponibles para las plantas permitiendo un rápido rebrote. Nuestros resultados muestran que los grandes carnívoros pueden beneficiar a los productores primarios vía cambios en el comportamiento de sus presas, y que estos efectos están mediados por el tipo de hábitat. No obstante, la productividad primaria modula la intensidad de estos efectos, con altos niveles de productividad primaria amortiguando los efectos de cascada iniciados por el depredador tope.Fil: Donadio, Emiliano. University of Wyoming, Ecology and Department of Zoology and Physiology; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Buskirk, Steven W.. University of Wyoming, Ecology and Department of Zoology and Physiology; Estados Unido

Juvenile and adult mortality patterns in a vicuña (Vicugna vicugna) population

Neotropical ungulates are poorly understood with regard to age-specific mortality and how it relates to different mortality causes. During January 2008–April 2011, we investigated mortality patterns of calf (¨ 49% (n=93) and 91% (n=89) of the mortality in calves and adults, respectively. Body condition of adult vicunas killed by pumas varied seasonally and correlated with seasonal changes in primary productivity and forage and diet quality. Our results highlighted the importance of puma predation and low birth mass as proximate causes of vicuna mortality. How environmental factors (e.g., early summer precipitation) influence forage and ultimately mortality has yet to be determined.Fil: Donadio, Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Buskirk, Steven. University of Wyoming; Estados Unidos. University Avenue; Estados UnidosFil: Novaro, Andres Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin