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Formosa, Argentina

van der Heide G.,Fundacion ECO | Fernandez-Duque E.,Fundacion ECO | Fernandez-Duque E.,CONICET | Fernandez-Duque E.,University of Pennsylvania | And 2 more authors.
International Journal of Primatology | Year: 2012

Small-scale ecological variables, such as forest structure and resource availability, may affect primate groups at the scale of group home ranges, thereby influencing group demography and life-history traits. We evaluated the complete territories of 4 groups of owl monkeys (Aotus azarai), measuring and identifying all trees and lianas with a diameter at breast height ≥10 cm (n = 7485). We aimed to determine all food sources available to each of those groups and to relate food availability to group demographics. For analyses, we considered the core areas of the home range separately from the 80% home range. Our results showed that groups occupy territories that differ in size, species evenness, stem density, and food species' stem abundances. The territories differed in the availability of fruits, flowers, and leaves, and most fruit sources were unevenly distributed in space. Differences among territories were more pronounced for the whole range than they were for the core areas. Despite marked differences among territories in structure and food availability, the number of births and age at natal dispersal were quite similar, but 1 group had a consistently lower group size. Our results suggest that owl monkey groups occupy territories of different structure and composition and food availability, yet ones that contain similar quantities of, mostly, dry season fruit sources. We propose that groups inhabit these territories to overcome food shortages safely during limiting periods, specifically the dry season, in this markedly seasonal forest. The occupancy and defense of territories with strict boundaries may therefore be associated with food resources available during limiting seasons that may be the ones influencing life history patterns and demographics. © 2011 Springer Science+Business Media, LLC.


Fernandez-Duque E.,Fundacion ECO | Fernandez-Duque E.,CONICET | Fernandez-Duque E.,University of Pennsylvania | van der Heide G.,University of Texas at San Antonio
International Journal of Primatology | Year: 2013

Limited food resource availability during yearly dry seasons can influence population dynamics and direct life-history evolution. We examined actual food production during two dry seasons and its relationship to feeding, life history, and demography in territorial, monogamous, and pair-living owl monkeys (Aotus azarae azarae). To quantify food availability in 16.25 ha of gallery forest in the Argentinean Chaco, we collected phenological data, from dry season fruit sources (N = 894), twice a month, during July and August of 2008 and 2009. At the same time, we collected feeding data from the four groups (N = 1448 h) inhabiting that forest portion. We also examined demographic data on births, natal dispersal, and group size. Our data show that owl monkeys occupy territories, and core areas, that produce food consistently, even during harsh times. Following the 2009 drought, less fruit was available than in 2008, but the 50 % core areas produced fruit amounts comparable to the 80 % territories. Owl monkeys showed dietary flexibility; fruits were the most frequent food item in 2008, whereas all groups increased their consumption of leaves in 2009. Infant production was lower in 2008 than after the drought of 2009. Interbirth intervals between the 2 yr were longer than the mean for the population, and more individuals dispersed in 2008 than in 2009. Our study suggests that owl monkeys occupy territories that provide similar amounts of reliable dry season foods within the core areas. Although access to these core areas may allow them to overcome severe dry seasons, our findings underscored the difficulties of understanding the potential causal relationships between ecological factors and demographic and life-history parameters. © 2013 Springer Science+Business Media New York.


Juarez C.P.,CONICET | Rotundo M.A.,Fundacion ECO | Berg W.,Fundacion ECO | Fernandez-Duque E.,CONICET | Fernandez-Duque E.,University of Pennsylvania
International Journal of Primatology | Year: 2011

The benefits to researchers of capturing and collaring free-ranging primates are numerous, but so are the actual and potential costs to the individuals. We aimed to 1) evaluate quantitatively the possible demographic long-term costs of radio-collaring a free-ranging primate species, and 2) evaluate qualitatively the costs to the subjects and the overall benefits to the research program that results from monitoring a large number of groups with collared individuals during many years. Between 2000 and 2009, we captured, recaptured, and radio-collared 146 owl monkeys (Aotus azarai) to study the behavior, demography, and genetics of the species. To evaluate the potential long-term costs of the collaring procedures on the population, we compared the demographic composition of groups (n = 20) in our core study area with those of undisturbed groups (n = 20) in a control area within the same forest. Groups in both areas ranged in size between 2 and 5 individuals. Surprisingly, group size tended to be larger among the study groups owing to more infants and juveniles in those groups than in the control groups. The benefits to the research program have included, among others, the reliable identification of individuals, increased sample sizes, the recovery of specimens, studies of dispersal, outreach activities, and conservation education. Still, some of the benefits will become tangible only when the project persists on time; is fully approved and supported by local authorities; and has broad community participation, as well as conservation and education goals. Thus, any serious initiative to capture and collar individuals should be the result of an extremely careful evaluation of benefits and costs. © 2010 Springer Science+Business Media, LLC.


Erkert H.G.,University of Tubingen | Fernandez-Duque E.,Fundacion ECO | Fernandez-Duque E.,University of Pennsylvania | Rotundo M.,Fundacion ECO | Scheideler A.,Helmholtz Center Munich
Chronobiology International | Year: 2012

Among the more than 40 genera of anthropoid primates (monkeys, apes, and humans), only the South American owl monkeys, genus Aotus, are nocturnal. However, the southernmostly distributed species, Aotus azarai azarai, of the Gran Chaco may show considerable amounts of its 24-h activity during bright daylight. Due to seasonal changes in the duration of photophase and climatic parameters in their subtropical habitat, the timing and pattern of their daily activity are expected to show significant seasonal variation. By quantitative long-term activity recordings with Actiwatch AW4 accelerometer data logger devices of 10 wild owl monkeys inhabiting a gallery forest in Formosa, Argentina, the authors analyzed the seasonal variation in the temporal niche and activity pattern resulting from entrainment and masking of the circadian activity rhythm by seasonally and diurnally varying environmental factors. The owl monkeys always displayed a distinct bimodal activity pattern, with prominent activity bouts and peaks during dusk and dawn. Their activity rhythm showed distinct lunar and seasonal variations in the timing and daily pattern. During the summer, the monkeys showed predominantly crepuscularnocturnal behavior, and a crepuscularcathemeral activity pattern with similar diurnal and nocturnal activity levels during the cold winter months. The peak times of the evening and morning activity bouts were more closely related to the times of sunset and sunrise, respectively, than activity-onset and -offset. Obviously, they were better circadian markers for the phase position of the entrained activity rhythm than activity-onset and -offset, which were subject to more masking effects of environmental andor internal factors. Total daily activity was lowest during the two coldest lunar months, and almost twice as high during the warmest months. Nighttime (21:0006:00h) and daytime (09:0018:00h) activity varied significantly across the year, but in an opposite manner. Highest nighttime activity occurred in summer and maximal daytime activity during the cold winter months. Dusk and dawn activity, which together accounted for 43 of the total daily activity, barely changed. The monkeys tended to terminate their nightly activity period earlier on warm and rainy days, whereas the daily amount of activity showed no significant correlation either with temperature or precipitation. These data are consistent with the dual-oscillator hypothesis of circadian regulation. They suggest the seasonal variations of the timing and pattern of daily activity in wild owl monkeys of the Argentinean Chaco result from a specific interplay of light entrainment of circadian rhythmicity and strong masking effects of various endogenous and environmental factors. Since the phase position of the monkeys' evening and morning activity peaks did not vary considerably over the year, the seasonal change from a crepuscularnocturnal activity pattern in summer to a more crepuscularcathemeral one in winter does not depend on a corresponding phase shift of the entrained circadian rhythm, but mainly on masking effects. Thermoregulatory and energetic demands and constraints seem to play a crucial role. © 2012 Informa Healthcare USA, Inc.


Caballero C.,Fundacion ECO | Jantus-Lewintre E.,Fundacion Para La Investigacion Del Hospital General Universitario Of Valencia | Carrato A.,Fundacion ECO | Carrato A.,University of Alcala | And 15 more authors.
Clinical and Translational Oncology | Year: 2014

Objectives: Under the auspices of the Foundation for Excellence and Quality in Oncology (ECO), the Translational Research in Oncology Medical Services Study (INTRO) was conducted with the aim of describing the current state of, and future expectations for translational cancer research in Spanish medical centres. The first step in the investigation was intended to analyse the current condition of the national Medical Oncology Services network by examining different aspects of the oncology research field. Methods: A descriptive and observational multicentre study was performed at a statewide level; information was collected by surveying a cross-section of all those responsible for Medical Oncology Services in Spain. Results: The survey was completed by key informants, who were selected independently by each service, between September 2010 and April 2011. We were able to gather comprehensive data from a total of 27 Spanish hospitals. These data enabled us to describe the allocation of human and material resources devoted to clinical and translational research across the Medical Oncology Services and to describe the organisational and functional components of these services and units. These data included information pertaining to the activities developed, their funding sources, and their functional dependence on other internal or external bodies. Finally, we explored the degree of dissemination and use of some specific techniques used for the genetic diagnosis of cancer, which have recently been introduced in Medical Oncology within the Spanish healthcare system. Conclusions: A wide range of variability exists between different oncology services in Spanish hospitals. Time should be spent reflecting on the need and opportunities for improvement in the development of translational research within the field of oncology. © 2013 Federación de Sociedades Españolas de Oncología (FESEO).

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