Natural history of the Red-backed Hawk, Buteo polyosoma: a review

Realizo una revisión de la literatura publicada sobre la historia natural del Aguilucho Común Buteo polyosoma complementada con mis observaciones de campo a lo largo de Chile, en particular de dos localidades: San Carlos de Apoquindo, 20 km al E de Santiago, y la Reserva Nacional Las Chinchillas, en Aucó, 300 km al N de Santiago. Además presento información cuantitativa de la dieta en Chile centro-N. La revisión la divido en 13 temas: distribución y taxonomía;nombres comunes; color del plumaje e identificación; morfometría y peso; historia de vida y reproducción; uso del hábitat; dieta; ritmos de actividad, tipos de vuelo y conductas de caza; agresión; vocalizaciones; abundancia; mortalidad; y otros hábitos. Con este trabajo se actualiza la información disponible para la especie y se la hace más accesible a la comunicad cientifica latino americana.In this papel I review the available literature on the natural history of the Red-backed Hawk, Buteo polyosoma. I supplement it with my own observations throughout Chile, specially my detailed studies at San Carlos de Apoquindo, 20 km E Santiago, and at Chinchilla National Reserve, at Aucó, 300 km N Santiago. I also document the diet of Red-backed hawks qualitatively in the second site. There view was covered in thirteen topics: Distribution and taxonomy; common names; color and field identification; morphometry and weight; life history and reproduction; habitat use; diet; activity, flight modes and hunting behavior; aggressions;vocalizations; abundance; mortality; and other topics. With this work, the current knowledge of the natural history of the Red-backed Hawk is updated, and made more accessible to the latinamerican scientific community

Historia natural del águila <i>Geranoaetus melanoleucus</i>: una revisión

Realizamos una revisión de la literatura y condensamos la informacion de diferentes autores acerca de la historia natural del águila Geranoaetus melanoleucus. Complementamos esta información con nuestras propias observaciones de campo entre localidades a lo largo de Chile. Ellas provienen de la Reserva Nacional Las Chinchillas (300 km al norte de Santiago), de San Carlos de Apoquindo (20 km al este de Santiago) y del Parque Nacional Torres del Paine (350 km al norte de Punta Arenas). Tratamos detalladamente los siguientes tópicos: distribución y taxonomía, color del plumaje e identificación, morfometría y peso, historia de vida y reproducción, uso del hábitat, dieta, ritmos de actividad, tipos de vuelo y conductas de caza, agresión, vocalizaciones, abundancia, mortalidad y otros hábitos.Con este trabajo se actualiza el estado del conocimiento de la biología del águila y se hace accesible la información que se ha documentado en revistas de circulación local y documentos de dificil acceso a la comunidad científica interesada.Natural history of the Grey Eagle-buzzard, Geranoaetus melanolucus: a review. We reviewed and summarized the literature concerning the natural history of the Grey Eagle-buzzard Geranoaetus melanoleucus. We suplement this information with our own field records from three sites along Chile. They are the Chinchilla National Reserve (300 km north of Santiago), San Carlos de Apoquindo (20km east of Santiago), and Torres del Paine National Park (350 km north of Punta Arenas).We covered in detail the following topics: distribution and taxonomy, color and field identification, morphometry and weigth, life history and reproduction, habitat use, diet, activity, flight modes and hunting behavior, aggression, vocalizations, abundance, mortality, and other topics. With this review we update the current knowledge of the biology of the Grey Eagly-buzzard, and render more accessible the information documented in journals and books of local circulation to the interested scientific community

UNEXPECTED LACK OF EFFECT OF THE INVASIVE AMERICAN MINK ON NESTING SURVIVAL OF FOREST BIRDS

Nest predation by invasive mammalian predators can cause major impacts on native bird populations. The American mink (Neovison vison) was recently introduced on Navarino Island in southern Chile. The mink established as a new terrestrial mesopredator on the island with documented impacts on waterfowl breeding success. However, little is known about mink effects on forest bird’s reproduction. Here, we investigated nest-predation rate by native predators and the invasive mink on open-cup nesting forest birds by using artificial and natural nests. In six different plots, we deployed a grid (7 x 2) of 14 artificial nests spaced by 50 m and at random heights from the ground. We used camera traps in each nest to identify predators. At each plot, we estimated predator relative abundance using camera traps, Sherman traps, and bird point counts. We estimated nest survival probability as a function of nest age, concealment, distance to the river, and nest height. Additionally, we monitored 43 natural nests of five open-cup nesting bird species. Contrary to expected, mink was not a main predator of nests, depredating only one natural nest. The native raptor Chimango Caracara (Milvago chimango) was the main nest predator, preying on 39.8% artificial nests and 27.0% natural nests. We also found evidence that Chimango Caracara learned to associate the artificial nests with the egg reward. We argue that the lower abundance of mink in the forest and a mismatch between mink peak activity patterns and bird breeding phenology can result in low depredation. Mink impacts, however, may be more pervasive in summer months and on fledglings when mink activity peaks, and more research should be conducted to assess these questions. Our results are valuable to better understand mink impacts on biodiversity and to prioritize conservation actions on species more severely affected

Sub-Antarctic Biocultural Conservation Program

Poster presented at the 2013 Ecological Society of America (ESA) Annual Meeting. This poster discusses research on assessing habitat preference of invasive American minks (Neovison vison) using trap-cameras in Navarino Island, Chile

Daily patterns of activity of passerine birds in a Magellanic sub-Antarctic forest at Omora Park (55°S), Cape Horn Biosphere Reserve, Chile

Abstract Ecosystems in the sub-Antarctic region can be subjected to extreme weather conditions year-round. Little data exist that show any relationship between climatic variables and activity patterns of passerine birds, despite the fact that weather patterns can have a dramatic influence on the foraging strategies of these birds in different seasons. Passerine birds must balance the risk of starvation and the risk of predation in accordance with variation in environmental variables. The goal of this study was to determine the relationship of season, habitat type and weather patterns with the daily activity patterns of three diurnal passerine bird species from different trophic guilds. Unlike most low-latitude passerine species, the three passerine bird species in Omora Park on Navarino Island do not show strict adherence to a bimodal activity pattern; instead, these birds show a variety of activity patterns throughout the year that differ by trophic guild and habitat type. These modifications in activity patterns may be an adaptation to minimize the risk of predation and starvation in the face of temperature-dependent food availability

Invasive expansion of the American Mink (Neovison vison) in the Cape Horn Biosphere Reserve, Chile

This article reports the continued expansion of the American mink to new sites in the Cape Horn Biosphere Reserve

Spray Drying of Xoconostle Juice: Interaction of Microstructure, Function, and Drying Operation Conditions

The xoconostle fruit (Opuntia matudae) is rich in polysaccharides, soluble fiber, simple phenols, betalains, and ascorbic acid. However, its consumption is limited due to its high acidity. Spray drying could be a technological option to strengthen the sustainability of xoconostle giving a re-valorization as a possible natural additive for the food industry. The food powders have to be designed considering aspects related to the effect of processing conditions on final quality properties; in this case, the effect of different drying air temperatures was evaluated on moisture content, water activity (Aw), glass transition temperature, microstructure, antioxidant activity, phenolic, and betalain compounds. For all cases, the drying air temperature had a positive effect on physical stability, at low levels of water activity and moisture content, and glass transition temperature (Tg) was increased. The biological functionality (assessed through phenolics, betalain compounds, and antioxidant activity) was also kept constant for all processing conditions investigated. However, the most evident changes were observed at microscopic scale analyzed through morphometric parameters

Experiencia clínica: kanamicina a dosis bajas en infecciones del tracto urinario

Se estudiaron 35 pacientes con diferentes tipos de infección urinaria, los cuales fueron tratados con kanamicina a la dosis de 500 mgs. por día durante 7 días. Fue posible de esta manera controlar el 60 por ciento de las bacterias del grupo en mención. Este resultado es considerado satisfactorio por los autores. Con la dosis empleada no se observaron manifestaciones secundarias atribuíbles al medicamento. A esta dosis es posible administrarlo por un período de tiempo más prolongado que lo habitua