Ecología trófica y tafonomía del Jote de cabeza negra, Coragyps atratus (Cathartidae), y su comparacion con los Cathartidae del Noroeste Patagónico

Tesis presentada para optar al Grado de Doctor en Ciencias NaturalesFil: Ballejo, Fernando. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin

Framing of visual content shown on popular social media may affect viewers’ attitudes to threatened species

Content published on social media may affect user’s attitudes toward wildlife species. We evaluated viewers’ responses to videos published on a popular social medium, focusing particularly on how the content was framed (i.e., the way an issue is conveyed to transmit a certain meaning). We analyzed videos posted on YouTube that showed vultures interacting with livestock. The videos were negatively or positively framed, and we evaluated viewers’ opinions of these birds through the comments posted. We also analyzed negatively framed videos of mammalian predators interacting with livestock, to evaluate whether comments on this content were similar to those on vultures. We found that the framing of the information influenced the tone of the comments. Videos showing farmers talking about their livestock losses were more likely to provoke negative comments than videos not including farmer testimonies. The probability of negative comments being posted on videos about vultures was higher than for mammalian predators. Finally, negatively framed videos on vultures had more views over time than positive ones. Our results call for caution in the presentation of wildlife species online, and highlight the need for regulations to prevent the spread of misinformed videos that could magnify existing human-wildlife conflicts.Fil: Ballejo, Fernando. 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: Plaza, Pablo. 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: 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; Argentin

A long and troublesome journey: People's perceptions and attitudes along the migratory path of a scavenger bird

In recent decades, there has been a growing interest in integrating the social sciences and conservation studies to inform a more realistic management approach. Indeed, an understanding of people's perception of fauna helps in the evaluation of possible conflicts with humans, and provides tools to solve these conflicts. However, perceptions may change along a species geographical distribution. Scavenger birds are not exempt from these conflicts as many farmers blame them for attacking and killing livestock. We evaluated the knowledge, perceptions and attitude of people regarding New World vultures along a migratory path in South America. We conducted 114 interviews with farmers in six different localities between Argentine Patagonia and central Bolivia. About half (48.2%) of the interviewees considered vultures harmful to livestock and a substantial number (24.5%) considered killing these birds as a solution for the conflict. The perception of the damage caused by these birds was worse in vultures wintering and breeding areas, than along the migration route. People with a higher level of education and greater numbers of livestock exhibited more negative perceptions. However, many people (53%) still believed that scavenger birds are important for the environment. Our results suggest that acknowledgment of services provided by scavengers makes killing of scavengers less likely. Educational strategies are needed to increase levels of appreciation toward the ecosystem services provided by vultures, over those of perceived damages.Fil: Ballejo, Fernando. 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. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Graña Grilli, Maricel. 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. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: 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; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentin

Black Vulture (Coragyps atratus) seasonal diet in rural and urban areas of north-western Patagonia

El estudio de la dieta de aves carroñeras es relevante porque estas especies cumplen un importante rol en la eliminación de cadáveres, reduciendo el desarrollo y exposición de patógenos sobre los tejidos cadavéricos. El objetivo de este trabajo es estudiar la dieta del Jote Cabeza Negra (Coragyps atratus) a lo largo del año y evaluar la relación entre los restos que consume y el hábitat utilizado en el noroeste patagónico. Se colectaron 488 egagrópilas en dos dormideros comunales, uno ubicado en un ambiente urbano (Dina Huapi) y otro en un ambiente rural (Estancia Chacabuco). Los mamíferos exóticos fueron los más consumidos (principalmente Bos taurus, Lepus europaeus, Cervus elaphus y Ovis aries), seguidos por los artrópodos. Se encontró una diferencia en la selección de carroña entre ambos sitios, siendo los artrópodos y Lepus europaeus más comunes en Estancia Chacabuco y Bos taurus y las aves en Dina Huapi. Los individuos de Dina Huapi presentaron una selección de carroña uniforme a lo largo del año, mientras que los de Estancia Chacabuco mostraron una correlación negativa en el consumo de mamíferos y artrópodos, lo que podría indicar una relación entre la disponibilidad de carroña y el consumo de artrópodos.The relevance of the study of the diet of scavenger birds relies on the important role they play as carcass removers, reducing exposure and development of pathogens in cadaveric tissues. The aim of this study is to examine the diet of the Black Vulture (Coragyps atratus) throughout an entire year and to evaluate the relationship between diet and habitat use in north-western Patagonia. A total of 488 pellets were collected in two roosts located in an urban (Dina Huapi) and a rural environment (Estancia Chacabuco). Exotic mammals (mainly Bos taurus, Lepus europaeu, Cervus elaphus and Ovis aries) were the most consumed items, followed by arthropods. A difference was found in the selection of carrion between sites, being arthropods and Lepus europaeus more common in Estancia Chacabuco and Bos taurus and birds in Dina Huapi. Dina Huapi individuals presented a uniform selection of carrion throughout the year, while those in Estancia Chacabuco showed a negative correlation in the consumption of mammals and arthropods, which could indicate a relationship between carrion availability and arthropod consumption

Taphonomy of bones remains from pellets of Coragyps atratus (black vulture) in the northwest of the argentinian Patagonia

Existen diversos estudios actualísticos en tafonomía sobre diferentes especies de aves de presa. Sin embargo, este tipo de trabajos en aves carroñeras no había sido considerado hasta el momento en Argentina, a pesar que ellas cumplen un papel fundamental en la alteración y transporte de cadáveres. Coragyps atratus (jote de cabeza negra) tiene la particularidad de formar posaderos comunales cercanos a áreas de actividades humanas y de alimentarse de animales de todos los tamaños, por lo que pueden interferir en la formación de sitios arqueológicos. El objetivo de este trabajo es realizar un análisis tafonómico sobre los restos óseos recuperados de egagrópilas de C. atratus en el noroeste patagónico, con el fin generar herramientas que permitan identificar a estas aves como posibles agentes acumuladores. Se recolectaron 469 egagrópilas distribuidas en tres posaderos del Noroeste patagónico. Se identificaron los elementos recuperados y se evaluaron los grados de alteraciones por ácidos gástricos. Lepus europaeus y Ovis aries dominaron las muestras. Los elementos más representativos pertenecen al autopodio, principalmente falanges. Todos ellos muestran signos de digestión, que van desde porosidades superficiales, perforaciones y fracturas, con la desaparición de la médula en el caso de varias falanges; denotando diferencias en relación al tamaño de la presa consumida.There are several actualistic taphonomic studies regarding different species of birds of prey. However, the studies focus on scavenger birds have been scarcely considered in Argentina, despite the fact that they play a fundamental role in the alteration and transportation of carcasses. A peculiar characteristic of Coragyps atratus (black vulture) is that it builds communal roosts near places where human activities are developed and it feeds on animals of varying size, which may interfere with the formation of archaeological sites. The aim of this study is to perform a taphonomic analysis of the bones remains retrieved from pellets of C. atratus in the Northwest of Patagonia, with the purpose of creating tools that allow the identification of these birds as possible accumulator agents. 469 pellets, distributed in the three roosts of the patagonic norhtwest, were gathered. The elements retrieved were identified and the degrees of alterations caused by gastric acids were evaluated. Lepus europaeus and Ovis aries predominate in the samples. The main elements belong to the articular bones, mainly phalanges. They all show signs of digestion, from surface porosities to perforations and fractures, and in the case of several phalanges, the disappearance of marrow, denoting differences regarding the size of the ingested prey.Fil: Ballejo, Fernando. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Anatomía Comparada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Fernández, Fernando Julián. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Anatomía Comparada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: De Santis, Luciano J. M.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Anatomía Comparada; Argentin

Taphonomy of bones remains from pellets of Coragyps atratus (black vulture) in the northwest of the argentinian Patagonia

Existen diversos estudios actualísticos en tafonomía sobre restos de presas de diferentes especies de aves raptoras. Sin embargo, este tipo de trabajos en aves carroñeras ha sido escasamente considerado hasta el momento en Argentina, a pesar que ellas cumplen un papel fundamental en la alteración y transporte de cadáveres. Coragyps atratus (jote de cabeza negra) tiene la particularidad de formar posaderos comunales cercanos a áreas de actividades humanas y de alimentarse de animales de todos los tamaños, por lo que pueden interferir en la formación de sitios arqueológicos. El objetivo de este trabajo es realizar un análisis tafonómico sobre los restos óseos recuperados de egagrópilas de C. atratus en el Noroeste patagónico, con el fin de generar herramientas que permitan identificar a estas aves como posibles agentes acumuladores. Se recolectaron 469 egagrópilas distribuidas en tres posaderos del Noroeste patagónico. Se identificaron los elementos recuperados y se evaluaron los grados de alteraciones por ácidos gástricos. Lepus europaeus y Ovis aries dominaron las muestras. Los elementos más representativos pertenecen al autopodio, principalmente falanges. Todos ellos muestran signos de digestión, que van desde porosidades superficiales, perforaciones y fracturas, con la desaparición de la médula en el caso de varias falanges; denotando diferencias en relación al tamaño de la presa consumida.There are several actualistic taphonomic studies regarding different species of birds of prey. However, the studies focus on scavenger birds have been scarcely considered in Argentina, despite the fact that they play a fundamental role in the alteration and transportation of carcasses. A peculiar characteristic of Coragyps atratus (black vulture) is that it builds communal roosts near places where human activities are developed and it feeds on animals of varying size, which may interfere with the formation of archaeological sites. The aim of this study is to perform a taphonomic analysis of the bones remains retrieved from pellets of C. atratus in the Northwest of Patagonia, with the purpose of creating tools that allow the identification of these birds as possible accumulator agents. 469 pellets, distributed in the three roosts of the patagonic norhtwest, were gathered. The elements retrieved were identified and the degrees of alterations caused by gastric acids were evaluated. Lepus europaeus and Ovis aries predominate in the samples. The main elements belong to the articular bones, mainly phalanges. They all show signs of digestion, from surface porosities to perforations and fractures, and in the case of several phalanges, the disappearance of marrow, denoting differences regarding the size of the ingested prey.Facultad de Ciencias Naturales y Muse

Trophic niche overlap among scavengers in Patagonia supports the condor-vulture competition hypothesis

Animals that share resources tend to use different foraging strategies in order to decrease potential competition. Scavenging birds using the same nutritional resources can segregate into different space and time scales. However, it has been suggested that when the species do not co-evolve to achieve such segregation competition may result. Our aim was to study the trophic niche overlap between three species of obligate scavengers, the Andean Condor Vultur gryphus, Turkey Vulture Cathartes aura and American Black Vulture Coragyps atratus, which are the main avian consumers of carcasses in north-western Patagonia. Black Vultures arrived in the area relatively recently, have expanded their distribution following human activities, and have been suggested to compete with the threatened condor. We collected pellets in communal roosts of the three species to determine their diet, and to estimate the diversity (Shannon Index) and diet similarity (Pianka overlap index). We found that the Turkey Vulture has greater niche breadth and, apart from domestic livestock, it incorporates smaller items such as fish, reptiles and a great number of birds, carnivores and mice. Although the Black Vulture diet includes arthropods, they feed primarily on introduced ungulates, overlapping more with condor diet when roosting far from urban centres. As these latter two species share the same food resource, human activities that positively affect the abundance of the Black Vulture could increase competition among them, with possible implications for the conservation of the Andean Condor.Facultad de Ciencias Naturales y Muse

Unravelling negative interactions between humans, mammalian carnivores and raptors in South America

Human-wildlife interactions can be negative when the needs and behavior of wildlife negatively influence human goals, or vice-versa, and management of these interactions may lead to conflict. Here, we review information on negative interactions between humans and wildlife in South America contained in 136 scientific publications, focusing on terrestrial mammalian predators and raptors. We found that most studies were conducted in Brazil, Argentina, Chile and Colombia. The methodology most commonly used to investigate negative interactions was interviews with rural inhabitants. Studies were performed mainly on interactions involving large felids such as Panthera onca and Puma concolor, and —to a lesser extent— on other mammalian predators and raptors such as eagles or scavenger birds. The main drivers of negative interactions involved perceived or actual impacts on human economy (material) (e.g., livestock or crop losses) or were based on non-material (intangible) aspects (e.g., fear, myths, and religious beliefs). The studies showed that negative attitudes and perceptions toward terrestrial mammalian predators and raptors are widespread in South America. Although non-lethal strategies for mitigation of negative interactions have been proposed, most are not widely used and lethal controls are still very common. A multidisciplinary approach is required, based on multiple actions (e.g., improving livestock practices, running educational programs, increasing stakeholder involvement, providing farmers with solutions), which would minimize negative interactions and promote coexistence between humans and wildlife. This is key to maintaining threatened species, ecological interactions and healthy environments in the anthropized landscapes of biodiverse South America.Las interacciones entre el ser humano y la fauna silvestre pueden ser negativas cuando las necesidades y el comportamiento de la fauna silvestre influyen negativamente en las metas de las personas, o viceversa, y manejar estas interacciones puede generar conflictos. En este artículo revisamos la información científica sobre este tipo de interacciones en 136 publicaciones realizadas en Sudamérica. Nos centramos en los mamíferos depredadores terrestres y en las aves rapaces . Encontramos que la mayoría de los estudios se realizaron en Brasil, Argentina, Chile y Colombia. La metodología más utilizada fueron las entrevistas a habitantes de zonas rurales. Los estudios se realizaron principalmente sobre interacciones con grandes félidos como Panthera onca y Puma concolor, y —en menor medida— sobre otros mamíferos depredadores y aves rapaces como las águilas o las aves carroñeras. Los impulsores principales de estas interacciones fueron los impactos -percibidos o reales- sobre la economía (materiales) como pérdidas de ganado o cultivos, o aspectos no materiales (intangibles) como miedo, mitos y creencias religiosas. Los estudios mostraron que las actitudes y percepciones negativas hacia los mamíferos depredadores y las aves rapaces están muy extendidas en Sudamérica. Aunque se propusieron estrategias no letales para mitigar las interacciones negativas, la mayoría no se utiliza ampliamente y los controles letales siguen siendo muy comunes. Se requiere un enfoque multidisciplinario, basado en diversas acciones (e.g., mejorar las prácticas ganaderas, realizar programas educativos, aumentar la participación de las partes interesadas, proporcionar soluciones a los agricultores) que minimicen las interacciones negativas y promuevan la coexistencia entre los seres humanos y la fauna silvestre. Esto es clave para conservar las especies amenazadas, fomentar las interacciones ecológicas y mantener entornos saludables en los paisajes antropizados de la biodiversa Sudamérica.Estación Experimental Agropecuaria BarilocheFil: Ballejo, Fernando. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Grupo de Investigaciones en Biología de la Conservación; ArgentinaFil: Ballejo, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Plaza, Pablo. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Grupo de Investigaciones en Biología de la Conservación; ArgentinaFil: Plaza, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Di Virgilio, Agustina. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Grupo de Investigaciones en Biología de la Conservación; ArgentinaFil: Di Virgilio, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lucherini, Mauro. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Grupo de Investigaciones en Biología de la Conservación; ArgentinaFil: Lucherini, Mauro. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gaspero, Pablo Gabriel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Guerisoli, María de las Mercedes. Museo Argentino de Ciencias Naturales Bernardino Rivadavia. Division Mastozoologia; ArgentinaFil: Guerisoli, María de las Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Novaro, Andres. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Novaro, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Novaro, Andres. Wildlife Conservation Society; ArgentinaFil: Funes, Martin. Wildlife Conservation Society; ArgentinaFil: Lambertucci, Sergio Agustin. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Grupo de Investigaciones en Biología de la Conservación; ArgentinaFil: Lambertucci, Sergio Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Small mammals (Didelphimorphia, Rodentia and Chiroptera) from Pampean Region, Argentina

We studied small mammal assemblages recovered from owl pellets collected at 11 locations throughout the Argentina's Pampean Region. We identified 21 species, including two marsupials, one bat, and 18 rodents. From the analysis of this dataset, we could distinguish three main groups of small mammals that currently inhabit the Pampean Region: 1) a group of taxa related to Pampean agroecosystems (Calomys spp., Akodon azarae, and Oligoryzomys flavescens); 2) a group of Brazilian species (Cavia aperea, Oxymycterus rufus, Necromys lasiurus, Necromys obscurus, Holochilus brasiliensis, and Monodelphis dimidiata); and 3) a group including species from Patagonia, Espinal and Monte phytogeographic provinces (Microcavia australis, Oligoryzomys longicaudatus, Eligmodontia typus, Graomys griseoflavus, and Akodon molinae). In addition, we documented the first record of a species of the large-bodied group of Calomys in Buenos Aires province, expanding its distribution ca. 420 km southward.Facultad de Ciencias Naturales y Muse

Presumed killers? Vultures, stakeholders, misperceptions, and fake news

Vultures and condors are among the most threatened avian species in the world due to the impacts of human activities. Negative perceptions can contribute to these threats as some vulture species have been historically blamed for killing livestock. This perception of conflict has increased in recent years, associated with a viral spread of partial and biased information through social media and despite limited empirical support for these assertions. Here, we highlight that magnifying infrequent events of livestock being injured by vultures through publically shared videos or biased news items negatively impact efforts to conserve threatened populations of avian scavengers. We encourage environmental agencies, researchers, and practitioners to evaluate the reliability, frequency, and context of reports of vulture predation, weighing those results against the diverse and valuable contributions of vultures to environmental health and human well-being. We also encourage the development of awareness campaigns and improved livestock management practices, including commonly available nonlethal deterrence strategies, if needed. These actions are urgently required to allow the development of a more effective conservation strategy for vultures worldwide.Peer reviewe