746 resultados para COMMUNAL NESTING
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A extracção clandestina de areia, nas faixas costeiras e nos leitos das ribeiras, tem sido prática de muitos agregados familiares cabo-verdianos. Nas últimas décadas, a praia de Calhetona (Ilha de Santiago) foi um dos muitos locais que sofreram degradação ambiental significativa, devido à realização desta actividade sem quaisquer planos de extracção e de posterior recuperação das áreas degradadas. Este trabalho, através da conjugação de recolha de dados por inquérito, observação directa e pesquisa documental e bibliográfica, teve como objectivos a caracterização da comunidade (que habita no bairro de Ponta Calhetona) que se dedica à extracção de areia na praia de Calhetona, a descrição da dinâmica da actividade extractiva, a avaliação da percepção que a comunidade tem relativamente às consequências da sua actividade e a descrição do impacte ambiental resultante da extracção de areia. Da análise dos inquéritos, efectuados em Fevereiro de 2012, a 25 chefes de agregados familiares que efectuam a extracção de areia na praia de Calhetona, constata-se que estes são maioritariamente mulheres, predominantemente com idade compreendida entre os 40 e os 59 anos, domésticas, com baixa escolaridade, com famílias numerosas e/ou alargadas a seu cargo e dedicando-se à extração de areia à mais de 10 anos. Os inquiridos, face à situação de vulnerabilidade económica, à falta de emprego e à grande procura de areia para a construção civil, vêem nesta actividade uma fonte de rendimento. Contudo, o proveito obtido desta actividade difícil e potencialmente perigosa é reduzido. Quem efectivamente beneficia são os camionistas que compram a areia a quem procede à extracção e a vendem ao consumidor final pelo dobro do preço. Os inquiridos demonstram uma consciência generalizada dos diversos impactes ambientais negativos resultantes da sua actividade, mas alegam que a extracção de areia é uma das poucas alternativas existentes para providenciar o sustento dos seus agregados familiares. Com base na comparação do estado actual da praia de Calhetona com relatos de habitantes locais, relativos às características da mesma no passado, verifica-se que nos últimos 40-50 anos, desde que se iniciou a intensa extracção de areia nesta praia, o seu aspecto físico se degradou claramente. Essa degradação caracteriza-se principalmente pelo recuo da linha de costa, pela quase ausência de areia e pela salinização dos solos localizados nas proximidades da praia, para além dos consequentes impactes negativos sobre a desova das tartarugas e o turismo balnear.
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Only a few studies, and mostly in temperate climates in Europe, have examined the breeding and diet of long-eared owls (Asia otus) compared to studies of cavity-breeding owls, possibly because of the difficulties in reaching the nests of the former. Here we studied a population of long-eared owls, monitoring the diet of breeding owls and that of owls at a communal roost, every two to three months during 2006 -2009, in a semi-arid region in Israel. It was found that the studied owls produced more young than in most countries in Europe. Diet was not associated with breeding parameters of the owls, whereas laying date was negatively correlated with both clutch size and number of nestlings. We found that more social voles (Microtus socialis) and fewer birds and house mice (Mus musculus) made up the diet at nests than that of adults at the roosts. The diet and breeding of long-eared owls in Israel differ from that in Europe, with birds and mice comprising an important part of the diet, in addition to voles.
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El projecte té com a objectiu general descriure accions comunitàries relacionades amb el menjar i la cohesió social. L’objectiu específic del projecte és recollir bones pràctiques d’entitats de Barcelona que treballin sobre la cohesió social i els espais alimentaris amb l’objectiu de dinamitzar l’intercanvi d’elements culturals, entre d’altres. La metodologia emprada en aquest treball ha estat un estudi descriptiu transversal de tipus qualitatiu, tenint en compte les tècniques emprades: anàlisi documental, observació participant i entrevistes a professionals. Les experiències analitzades per a la realització del treball resulten experiències d’èxit que basen la seva activitat en la utilització de l’alimentació com a eina per treballar la cohesió social, a partir de la creació d’espais comunitaris que permeten l’intercanvi d’elements culturals entre els participants
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Contexte et cadre: L'Institut universitaire de médecine sociale et préventive (IUMSP) de Lausanne a été mandaté par la Fondation Leenaards pour élaborer un cadre pour l'évaluation de l'impact d'un processus communautaire sur la santé des aînés dans la ville d'Yverdon, appelé "Quartiers solidaires". "Quartiers solidaires" est une méthodologie de développement communautaire, créée par l'unité de travail social communautaire de Pro Senectute Vaud. Elle a pour but d'améliorer la qualité de vie actuelle et future des personnes âgées au sein de leur quartier. Pour atteindre cet objectif, les habitants, et en particulier les aînés, sont invités à devenir auteurs et acteurs de leurs propres projets en créant une communauté locale. Le projet "Quartiers solidaires" à Yverdon s'inscrit par ailleurs dans le cadre d'un projet communal de politique d'action sociale de la ville, Qualité de vie, s'appliquant au niveau de la ville et impliquant divers acteurs et instances. L'IUMSP propose, pour l'élaboration de ce cadre, d'utiliser un outil : le "modèle de catégorisation des résultats". Cet outil, appelé aussi SMOC (Swiss Model for Outcome Classification), permet à tous les partenaires impliqués dans le projet Quartiers solidaires d'établir ensemble un état de situation à laquelle ils sont confrontés (c'est à dire une analyse des problèmes auxquels ils doivent faire face), ainsi qu'une théorie d'action (c'est à dire un schéma qui structure les activités, en cours et planifiées, selon les divers objectifs visés). Cet outil, caractérisé par sa démarche participative, a été utilisé dans le cadre d'ateliers réunissant les différentes parties prenantes du projet. [...] Le modèle est basé sur la santé dans sa définition la plus large (telle que définie par l'OMS), englobant donc la qualité de vie, et est en adéquation avec l'approche écologique, qui repose sur une vision élargie des déterminants de la santé. [Auteurs, p. 7-8]
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In their invasive ranges, Argentine ant populations often form one geographically vast supercolony, genetically and chemically uniform within which there is no intraspecific aggression. Here we present regional patterns of intraspecific aggression, cuticular hydrocarbons (CHCs) and population genetics of 18 nesting sites across Corsica and the French mainland. Aggression tests confirm the presence of a third European supercolony, the Corsican supercolony, which exhibits moderate to high levels of aggression, depending on nesting sites, with the Main supercolony, and invariably high levels of aggression with the Catalonian supercolony. The chemical analyses corroborated the behavioural data, with workers of the Corsican supercolony showing moderate differences in CHCs compared to workers of the European Main supercolony and strong differences compared to workers of the Catalonian supercolony. Interestingly, there were also clear genetic differences between workers of the Catalonian supercolony and the two other supercolonies at both nuclear and mitochondrial markers, but only very weak genetic differentiation between nesting sites of the Corsican and Main supercolonies (F(ST) = 0.06). A detailed comparison of the genetic composition of supercolonies also revealed that, if one of the last two supercolonies derived from the other, it is the Main supercolony that derived from the Corsican supercolony rather than the reverse. Overall, these findings highlight the importance of conducting more qualitative and quantitative analyses of the level of aggression between supercolonies, which has to be correlated with genetic and chemical data.
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Les partis politiques ont comme vocation de structurer le débat démocratique et de constituer un trait d'union entre le citoyen et l'Etat. En Suisse, ils sont fortement sollicités en raison de l'importante quantité de scrutins organisés chaque année aux échelons communal, cantonal et national, mais leur organisation reste très peu professionnalisée. Comme ils doivent par ailleurs faire face à l'effritement de leur base partisane et à l'inflation des coûts de la politique, le risque est grand qu'ils soient mis en difficulté dans l'accomplissement de leur tâche d'intégration et de formation de l'opinion. Cette étude se concentre sur les pratiques de financement des partis cantonaux et nationaux du PDC, du PRD, du PS, de l'UDC et des Verts. S'appuyant sur les données empriques récoltées en 1997 et en 2007, elle décrit dans quelle mesure les moyens financiers des partis ont évolué au cours des dix dernières années. Les analyses portent sur le volume et l'origine des fonds et elles permettent notamment de saisir comment s'articulent les clivages en matière de financement. Die politischen Parteien haben die Aufgabe, die demokratische Debatte zu strukturieren und ein verbindendes Element zwischen dem Bürger und dem Staat zu bilden. In der Schweiz werden sie angesichts der grossen Anzahl jährlich auf kommunaler, kantonaler und nationaler Ebene durchgeführten Wahlgänge besonders stark beansprucht, ihre Organisationen sind aber wenig professionalisiert. Da sich die Parteien heute mit abnehmenden Parteienbindungen und steigenden Kosten der Politik konfrontiert sehen, steigt das Risiko, dass sie ihre Aufgaben der Integration und der politischen Meinungsbildung kaum mehr wahrnehmen können. Diese Arbeit konzentriert sich auf die Finanzierungspraktiken der kantonalen und nationalen Parteien CVP, FDP, SP, SVP und Grüne. Die Analysen stützen sich ab auf empirische Angaben zu Herkunft und Umfang der Parteifinanzen, die in den Jahren 1997 und 2007 erhoben wurden und erlauben es, die Unterschiede hinsichtlich der Finanzierung zu erläutern.
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1. The environment of parasites is determined largely by their hosts. Variation in host quality, abundance and spatial distribution affects the balance between selection within hosts and gene flow between hosts, and this should determine the evolution of a parasite's host-range and its propensity to locally adapt and speciate. 2. We investigated the relationship between host spatial distribution and (1) parasite host range, (2) parasite mobility and (3) parasite geographical range, in a comparative study of a major group of avian ectoparasites, the birds fleas belonging to the Ceratophyllidae (Siphonaptera). 3. Flea species parasitizing colonial birds had narrower host ranges than those infesting territorial nesters or birds with an intermediate level of nest aggregation. 4. The potential mobility and geographical ranges of fleas decreased with increasing level of aggregation of their hosts and increased with the fleas' host ranges. 5. Birds with aggregated nest distribution harboured more flea species mainly due to a larger number of specialists than solitarily nesting hosts. 6. These results emphasize the importance of host spatial distribution for the evolution of specialization, and for local adaptation and speciation in Ceratophyllid bird fleas.
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Wie steht es um die Beteiligung der Stimmbürgerinnen und Stimmbürger an lokalen Wahlen? Es mag angesichts der Bedeutung der Gemeinden im politischen Leben in der Schweiz erstaunen, dass zur Wahlbeteiligung auf kommunaler Ebene keine offiziellen, landesweiten Statistiken vorliegen. Damit waren Fragen nach dem Ausmass der lokalen Beteiligung im Verhältnis zur Beteiligung an nationalen Wahlen oder nach der Entwicklung der Beteiligung über die Zeit hinweg bis anhin kaum zu beantworten. Ebenso fehlte es an Kenntnissen über unterschiedliche regionale Beteiligungskulturen und über den Einfluss von institutionellen Faktoren, wie beispielsweise der Existenz eines Gemeindeparlaments auf die Höhe der Wahlbeteiligung. Auf der Basis von fünf gesamtschweizerischen Gemeindeschreiberbefragungen, die in regelmässigen Abständen seit Ende der 1980er Jahren durchgeführt wurden, wird in dieser Publikation erstmals eine umfassende Gesamtsicht zu den lokalen Wahlen in der Schweiz präsentiert. Behandelt werden neben charakteristischen Besonderheiten lokaler Wahlen (Wahlort, Wahlsystem), Fragen zur Umstrittenheit und den Ergebnissen dieser Wahlen. Im Mittelpunkt steht die Wahlbeteiligung: Es wird gezeigt, wie sich diese über die Zeit hinweg verändert hat, wie sie sich im Verhältnis zur Beteiligung an kantonalen und nationalen Wahlen verhält und welche Faktoren zu einer hohen Wahlbeteiligung führen. Qu'en est-il de la participation électorale aux élections locales? De manière surprenante, sur le plan national, il n'existe aucune statistique officielle concernant la participation aux élections communales et ce, malgré l'importance des communes dans la vie politique suisse. Ainsi, jusqu'à présent plusieurs questions restaient sans réponse : l'importance de la participation aux élections locales en comparaison avec celle de la participation aux élections fédérales, l'évolution dans le temps de la participation aux élections locales, les différentes cultures régionales de participation électorale et l'influence de facteurs institutionnels (comme l'existence d'un Parlement communal) sur la participation électorale. Sur la base de cinq enquêtes menées à intervalles réguliers depuis la fin des années 1980 auprès de secrétaires municipaux de l'ensemble de la Suisse, cette publication présente pour la première fois une vue d'ensemble détaillée des élections locales en Suisse. Cette publication traite, en plus des caractéristiques des élections locales (système électoral, lieu de vote), de questions relatives au caractère disputé de ces élections et de leurs résultats. Le point central de cette publication est la participation électorale : les questions concernant son évolution dans le temps, son comportement par rapport à la participation aux élections cantonales et fédérales ainsi que les facteurs générant une augmentation de la participation sont également abordées.
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Capsule Habitat parameters associated with 706 Barn Owl (Tyto alba) nesting boxes in Israel were analysed. Pairs bred in 259 of the boxes. The intensity of agricultural practices at nestbox sites were shown to have only a weak effect on aspects of Barn Owl breeding in this region.
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Référence bibliographique : Weigert, 346
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The dress code of paper wasps, like that of humans, is related to their social habits: species with a flexible nest-founding strategy have highly variable black-and-yellow markings. This color polymorphism facilitates individual recognition and might have been selected to permit complex social interactions.
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The mating behavior and reproductive strategies of Alpine whitefish like Coregonus zugensis (Nusslin) are poorly understood, probably because they spawn in deep water where direct observations are difficult. In this study, we interpret life-history and sperm quality traits of fish that we caught from their spawning place. We found that males invest heavily into gonadal tissue (up to 5.6% of their body weight), which is, in comparison to other fish, consistent with external fertilization, distinct pairing and moderate to high communal spawning, or no pairing and low to moderate communal spawning. Sperm competition theory and recent experimental studies on other salmonids predict that males optimize ejaculate characteristics in relation to the costs of sperm and the level of competition they have to expect: dominant males are predicted to invest less into ejaculate quality and to have slower spermatozoa than subdominant males. We found that spermatozoa of older males are slower than those of younger males. Moreover, older males have larger breeding tubercles, a secondary sexual trait that has, in some previous studies, been found to be linked to good condition and to good genetic quality. Our results suggest that C. zugensis has age-linked reproductive strategies, that multimale spawning is common, i.e., that sperm competition plays a significant role, and that older males are on average dominant over younger males at the spawning place.
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Eusocial animal societies are typified by the presence of a helper (worker) caste which predominantly cares for young offspring in a social group while investing little in their own direct reproduction. A key question is what determines whether an individual becomes a worker or leaves to initiate her own reproduction. In some insects, caste is determined nutritionally during development. In others, and in vertebrate societies, adults are totipotent and the cues that determine caste are less well known. The mate limitation hypothesis (MLH) states that a female's mating status acts as a cue for caste determination: females that mate become reproductives, while those that fail to mate become workers. The MLH is consistent with empirical observations in sweat bees showing that over the course of the nesting season, there are increases in both the proportion of females that become reproductives and the frequency of males in the mating pool. We modelled a foundress's offspring sex-ratio strategy to investigate whether an increasingly male-biased operational sex-ratio over time is evolutionarily stable under the MLH. Our results indicate that such a pattern could occur if early workers were more valuable than late workers. This pattern was then more likely if male mortality was high, if worker mortality was low, if the value of a worker was high and if the period over which workers can help was short. Our results suggest that the MLH can be evolutionarily stable, but only under restrictive conditions. Manipulative experiments are now required to investigate whether mating determines caste in nature.
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Reliable estimates of the post-release mortality probability of marine turtles after incidental by-catch are essential for assessing the impact of longline fishing on these species.Large numbers of loggerhead turtles Caretta caretta from rookeries in the northwestern Atlantic Ocean have been by-caught annually in the southwestern Mediterranean Sea since the 1980s, but nothing is known about their post-release mortality probability under natural conditions. Pop-up archival transmitting tags were attached to 26 loggerhead turtles following incidental capture by Spanish longliners. Hooks were not removed, and 40 cm of line was left in place. The post-release mortality probability during the 90 d following release ranged from 0.308 to 0.365, and was independent of hook location. When the post-release mortality probability was combined with previously reported estimates of the mortality probability before hauling, the aggregated by-catch mortality probability ranged from 0.321 to 0.378. Assuming a total annual by-catch of 10656 loggerhead turtles by the Spanish longline fleet operating in the southwestern Mediterranean, by-catch results in 3421 to 4028 turtle deaths annually. This range is equivalent to 8.5−10.1% of the approximately 40000 turtles inhabiting the fishing grounds used by Spanish longliners, most of them from rookeries in the northwestern Atlantic. As a consequence, the accumulated mortality during the oceanic stage is expected to be larger for those loggerhead turtles of Atlantic origin that spend several years in the Mediterranean Sea than for turtles of the same cohort that remain in the Atlantic. For this reason, the Mediterranean can be considered a dead end for loggerhead turtle populations nesting in the Atlantic, although the actual demographic relevance of by-catch mortality of loggerhead turtles in the Mediterranean remains unknown.
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This work compared the behaviour of pre-parturient sows housed in intensive confined and outdoor systems, during the morning and afternoon prior to delivery. Eight sows were kept individually in farrowing crates or in paddocks with access to fresh pasture from 8 to 10 days before expected parturition. All outdoor sows built a nest within 24 hours before farrowing. On the morning and afternoon before farrowing they spent 6.5% of the time collecting grass and 7.5% of the time organizing the nest. Outdoor sows were observed more often than confined sows rooting (4.60% vs. 0.25%), feeding (10.2% vs. 3.0%), standing (51% vs. 13%) and walking (8% vs. 0%). Indoor sows redirected the nesting behaviour to other behaviours like attempts to dig the ground, nosing, biting and rooting parts of the crate, feeder or drinker, during 4.7% of the time. They also spent more time than outdoor sows inactive (85% vs. 60%), lying (72% vs. 41%), drinking (2.1% vs. 0.5%) and vacuum chewing (3.7% vs. 0.1%). The pre-parturient behaviour of sows was considerably affected by the husbandry system. The outdoor system appears to be more appropriate for the sows' welfare than the conventional confinement.