158 research outputs found

    Distribución y aspectos poblacionales del lobo Ibérico en la provincia de Ourense

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    Para determinar el área de distribución del lobo en la provincia de Ourense (noroeste de España) se realizaron prospecciones de campo consistentes en itinerarios de muestreo para localizar indicios y se enviaron cuestionarios a los Agentes del Servicio de Conservación de la Naturaleza de la Xunta de Galicia y a las Sociedades de Cazadores del área de estudio. Los resultados se registraron sobre cuadrículas U.T.M. 10x10 Km. Se constata presencia del lobo en el 79,2% de las cuadrículas estudiadas, estimando el área de distribución en la provincia en 6.400 km2. Para la localización de los grupos familiares inicialmente se prospectó el territorio a nivel de cuadrículas U.T.M. 10x10 Km y en función de los resultados y la información recibida se eligieron determinadas zonas para realizar estaciones de escucha y espera. Determinamos durante el periodo de estudio la existencia de 25 grupos familiares. La densidad estimada en la provincia es de 2,10 – 3,28 lobos /100 km2. De los casos de mortalidad conocidos entre enero de 1999 y abril de 2002 (n=37), un elevado porcentaje se debió a atropellos (70,27%) principalmente en dos vías concretas y un 8,10% correspondió a envenenamientos. Actualmente la densidad del lobo en Ourense es superior a la obtenida en provincias limítrofes, pero amenazas de origen antrópico tanto directas (veneno, persecución ilegal...) como indirectas (incendios forestales, grandes infraestructuras viales, parques eólicos...) pueden estar condicionando la existencia de grupos familiares e incluso la presencia de la especie en determinadas zonas

    Distribución y aspectos poblacionales del lobo Ibérico (Canis lupus signatus) en las provincias de Pontevedra y A Coruña (Galicia)

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    Para determinar el área de distribución del lobo en las provincias de Pontevedra y A Coruña se realizaron itinerarios de muestreo y se enviaron cuestionarios a los Agentes de Medio Ambiente de la Xunta de Galicia y a las Sociedades de Cazadores del área de estudio. Los resultados se representaron en cuadrículas U.T.M. 10x10 Km. Se ha confirmado la presencia del lobo en el 67,05% de las cuadrículas del área de estudio. La especie se distribuye de forma continua en ambas provincias, donde estimamos un área de distribución de 6.400 km2 en la provincia de A Coruña y 3.200 km2 en la de Pontevedra, ocupando principalmente el área montañosa de la Dorsal Gallega y el occidente de A Coruña; esta última zona está conectada con el resto del área de distribución del lobo en Galicia a través del norte de la provincia de Pontevedra. Para la localización de las manadas se muestreó el territorio a nivel de cuadrícula U.T.M. 10x10 Km, y en las zonas donde se detectó una mayor concentración de indicios, se realizaron estaciones de escucha y espera con el fin de localizar la presencia de manadas (cachorros y adultos). Se determinó la presencia de 29 manadas (14 en la provincia de A Coruña y 15 en Pontevedra), de las cuales se confirmó la reproducción del 52%. Se ha estimado un tamaño poblacional para la provincia de A Coruña entre 87-129 lobos (1,36-2,02 lobos/100 Km2) y entre 95-140 para la provincia de Pontevedra (2,97-4,38 lobos/100 Km2). Las zonas de mayor densidad se localizaron en la Dorsal Gallega. Se han localizado algunas manadas en áreas muy humanizadas, lo que podría explicar que la principal causa de mortalidad conocida entre enero de 2000 y octubre de 2003 (n=29) sea el atropello (n=21)

    Monitoring wolf populations using howling points combined with sign survey transects

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    Wolves respond to simulated howling, especially during the mating and breeding seasons. Simulated howling points are, therefore, commonly used by many wolf researchers around the world to estimate pack numbers in a given area. A large amount of information is available on various pack breeding areas in Asturias, the only region in north-western Spain where the Iberian wolf (Canis lupus signatus, Cabrera 1907) is not classed as a game species. Wolf research began there in the early 1980s. We present the results of the latest study on population status, conducted between July and November, 2001. Using sampling transects to detect wolf scat and scratch marks and designated howling and observation points, twenty one (21) wolf packs were definitely located, with two others considered “likely”. Nineteen (19) packs were detected using howling points (n=314). The results of this study show that simulated howling points and sampling transects are reliable and inexpensive way of detecting wolf packs

    Wolf habitat selection when sympatric or allopatric with brown bears in Scandinavia

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    Habitat selection of animals depends on factors such as food availability, landscape features, and intra- and interspecific interactions. Individuals can show several behavioral responses to reduce competition for habitat, yet the mechanisms that drive them are poorly understood. This is particularly true for large carnivores, whose fine-scale monitoring is logistically complex and expensive. In Scandinavia, the home-range establishment and kill rates of gray wolves (Canis lupus) are affected by the coexistence with brown bears (Ursus arctos). Here, we applied resource selection functions and a multivariate approach to compare wolf habitat selection within home ranges of wolves that were either sympatric or allopatric with bears. Wolves selected for lower altitudes in winter, particularly in the area where bears and wolves are sympatric, where altitude is generally higher than where they are allopatric. Wolves may follow the winter migration of their staple prey, moose (Alces alces), to lower altitudes. Otherwise, we did not find any effect of bear presence on wolf habitat selection, in contrast with our previous studies. Our new results indicate that the manifestation of a specific driver of habitat selection, namely interspecific competition, can vary at different spatial-temporal scales. This is important to understand the structure of ecological communities and the varying mechanisms underlying interspecific interactions

    Growth velocity in children with environmental enteric dysfunction is associated with specific bacterial and viral taxa of the gastrointestinal tract in Malawian children

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    Environmental enteric dysfunction (EED) is characterized by diffuse villous atrophy of the small bowel. EED is strongly associated with stunting, a major public health problem linked to increased childhood morbidity and mortality. EED and subsequent stunting of linear growth are surmised to have microbial origins. To interrogate this relationship, we defined the comprehensive virome (eukaryotic virus and bacteriophage) and bacterial microbiome of a longitudinal cohort of rural Malawian children with extensive metadata and intestinal permeability testing at each time point. We found thirty bacterial taxa differentially associated with linear growth. We detected many eukaryotic viruses. Neither the total number of eukaryotic families nor a specific viral family was statistically associated with improved linear growth. We identified 3 differentially abundant bacteriophage among growth velocities. Interestingly, there was a positive correlation between bacteria and bacteriophage richness in children with subsequent adequate/moderate growth which children with subsequent poor growth lacked. This suggests that a disruption in the equilibrium between bacteria and bacteriophage communities might be associated with subsequent poor growth. Future studies of EED and stunting should include the evaluation of viral communities in addition to bacterial microbiota to understand the complete microbial ecology of these poorly understood entities

    Human Resource Flexibility as a Mediating Variable Between High Performance Work Systems and Performance

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    Much of the human resource management literature has demonstrated the impact of high performance work systems (HPWS) on organizational performance. A new generation of studies is emerging in this literature that recommends the inclusion of mediating variables between HPWS and organizational performance. The increasing rate of dynamism in competitive environments suggests that measures of employee adaptability should be included as a mechanism that may explain the relevance of HPWS to firm competitiveness. On a sample of 226 Spanish firms, the study’s results confirm that HPWS influences performance through its impact on the firm’s human resource (HR) flexibility

    Highlighting the drastic body size decline in Cantabrian Brown Bear, Chamois and Wild Horse during the Holocene

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    [EN] During the Holocene, Iberian ecosystems have changed dramatically in response to different biotic and abiotic drivers. Typically, the impact of these changes on ecosystems is assessed in terms of the variation of diversity in the communities that compose them. However, there are a wide variety of population-specific parameters of vital importance for the maintenance of the structure and health of these ecosystems. In this study, we have focused on the drastic decrease in body size (body mass) during the Holocene in three large mammal species in the Cantabrian Mountains. Namely, the brown bear (Ursus arctos), the chamois (Rupicapra pyrenaica parva) and the wild horse (Equus ferus ferus). The research combines the analysis of new findings with an exhaustive compilation of previously published data to assess changes in the body size of these species at different geographical (European, Iberian and Cantabrian Regions) and chronological scales (during the Quaternary – i.e. Pleistocene and Holocene). We aim at assessing the impact of anthropogenic and climatic factors on macromammal populations in the Iberian Peninsula, using new data obtained from the new archaeo-palaeontological site of Cueva de Llamazares (León, Spain). The results show that, although the final decline in body size during the Holocene occurred in the three species, each of them seems to have been driven by different factors. Bear populations seem more influenced by their mobility versus the potential impact of changing in human hunting dynamics, while changes in vegetation cover would have been most important for chamois, and the gradual effect of climate changes for horse populations. Research covering broad chronological ranges in the past helps understanding the present and future dynamics of these species, thus contributing to their conservation and managementSIThe author(s) disclosed receipt of the following financial sup-port for the research, authorship, and/or publication of this ar-ticle: This research activity was funded by the Research GroupQ-GEO (Geología Ambiental, Cuaternario y Geodiversidad, Universidad de León, León, Spain). D.F. was supported by theAyuda del Programa de Formación de Profesorado Universi-tario (FPU20/03389) and is a Ph.D. student at the Programade Doctorado en Biología at the Universidad Complutense de Madri

    Habitat selection by brown bears with varying levels of predation rates on ungulate neonates

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    In northern Eurasia, large carnivores overlap with semi-domestic reindeer (Rangifer tarandus) and moose (Alces alces). In Scandinavia, previous studies have quantified brown bear (Ursus arctos) spring predation on neonates of reindeer (mostly in May) and moose (mostly in June). We explored if habitat selection by brown bears changed following resource pulses and whether these changes are more pronounced on those individuals characterised by higher predatory behaviour. Fifteen brown bears in northern Sweden (2010–2012) were fitted with GPS proximity collars, and 2585 female reindeers were collared with UHF transmitters. Clusters of bear positions were visited to investigate moose and reindeer predation. Bear kill rates and home ranges were calculated to examine bear movements and predatory behaviour. Bear habitat selection was modelled using resource selection functions over four periods (pre-calving, reindeer calving, moose calving, and post-calving). Coefficients of selection for areas closer to different land cover classes across periods were compared, examining the interactions between different degrees of predatory behaviour (i.e., high and low). Bear habitat selection differed throughout the periods and between low and high predatory bears. Differences among individuals’ predatory behaviour are reflected in the selection of habitat types, providing empirical evidence that different levels of specialization in foraging behaviour helps to explain individual variation in bear habitat selection

    The diel niche of brown bears: constraints on adaptive capacity in human‐modified landscapes

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    [ENG] Diel activity rhythms, representing the behavioral pattern of the sleep–wake cycle, may be adjusted by wildlife in response to changes in environmental conditions. An increase in nocturnality is typically recognized as an adaptive strategy to segregate from humans and mitigate heat stress. Numerous studies have investigated spatial patterns and habitat use of large carnivores in human-modified landscapes, but little research has examined their activity rhythms. We compiled Global Positioning System data (2004–2022) for 139 brown bears Ursus arctos from six populations across Europe, representing a human-modified landscape, and the Greater Yellowstone Ecosystem, U.S.A., representing a landscape with limited human impact, which we used to calculate hourly movement rates as an activity proxy. Using a Bayesian approach to model the temporal autocorrelation of activity data, we tested if the extent of nocturnality in brown bears is modulated by intensity of human encroachment, accounting for primary productivity and maximum ambient temperature. All bear populations exhibited a predominantly bimodal, crepuscular pattern of activity, although Yellowstone bears were proportionally more crepuscular and diurnal. Whereas the effect of primary productivity was variable, all European populations became more nocturnal in response to higher human encroachment and reduced diurnal and crepuscular activity at higher summer temperatures, decreasing overall diel activity levels. Yellowstone bears displayed the greatest shift towards nocturnality among all populations in response to increasing human encroachment, and increased nocturnal activity to compensate for lower diurnal and crepuscular activity at higher summer temperatures. Our research indicates that European bears in human-modified landscapes may be reaching a limit in the behavioral plasticity they can manifest in their activity patterns, being already constrained into increased nocturnality. Our findings enhance the understanding of brown bear adaptive capacity to accommodate future changes, such as urbanization and increasing temperatures, to the ecosystems they inhabitSIThis work was supported by the Faculty of Veterinary Medicine, University of Zagreb (Croatia); U.S. Geological Survey; U.S. National Park Service; U.S. Fish and Wildlife Service; U.S. Forest Service; Wyoming Game and Fish Department; Montana Fish, Wildlife and Parks; Idaho Department of Fish and Game; Eastern Shoshone and Northern Arapaho Tribal Fish and Game Department; Swedish Environmental Protection Agency; the Norwegian Environmental Protection Agency; Wildlife Conservation Society, New York (U.S.A.). PC was funded by the European Union— NextGenerationEU National Biodiversity Future Center

    Testing the influence of habitat experienced during the natal phase on habitat selection later in life in Scandinavian wolves

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    Natal habitat preference induction (NHPI) occurs when characteristics of the natal habitat influence the future habitat selection of an animal. However, the influence of NHPI after the dispersal phase has received remarkably little attention. We tested whether exposure to humans in the natal habitat helps understand why some adult wolves Canis lupus may approach human settlements more than other conspecifics, a question of both ecological and management interest. We quantified habitat selection patterns within home ranges using resource selection functions and GPS data from 21 wolf pairs in Scandinavia. We identified the natal territory of each wolf with genetic parental assignment, and we used human-related characteristics within the natal territory to estimate the degree of anthropogenic influence in the early life of each wolf. When the female of the adult wolf pair was born in an area with a high degree of anthropogenic influence, the wolf pair tended to select areas further away from humans, compared to wolf pairs from natal territories with a low degree of anthropogenic influence. Yet the pattern was statistically weak, we suggest that our methodological approach can be useful in other systems to better understand NHPI and to inform management about human-wildlife interactions
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