616 research outputs found

    Fence and plough for Lapwings: Nest protection to improve nest and chick survival in Swiss farmland

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    Switzerland had up to 1000 Lapwing pairs breeding in the 1970s. Actually, there are some 200. The crash was mainly due to a poor productivity of 0.2 to 0.4 fledglings per pair and year. To achieve a fledging rate of at least 0.8 required for population stability, a Recovery Programme was initiated to support a small population of 10-25 pairs breeding in central Switzerland. In 2004 to 2006 all nests were marked and spared during field labour by the farmers. As a result of a well established cooperation with the local farmers, not a single nest was destroyed by agricultural activities. However, there was a high risk of nest desertion when farming activities took place during the period of egg laying. Therefore, it might be worth to postpone field labour for some days to allow clutch completion. In 2005 and 2006, but not in 2004, most nests were protected from ground predators by surrounding entire fields rather than individual clutches with electro-fences as used in sheep farming. While 95 % of clutches within the fences hatched successfully, 61 % of unprotected nests were predated. In 2006 the influence of predation on chick survival was investigated by radio-tagging 81 chicks soon after hatching. They had no difficulties to cross the electro-fences. Predation occurred mostly at night (73 %) and outside the fences (87 %). Of 46 chicks predated at night only one was taken inside an electro-fence. Daytime predation played a minor role (27 % of all chick predations) and occurred at the same rate inside and outside the electro-fence. Reproductive success in 2005 was an estimated 0.8 fledging young per pair and year. In 2006, however, it dropped to 0.25 due to heavy chick predation.In den 1970er Jahren umfasste der Brutbestand des Kiebitzes in der Schweiz ca. 1000 Paare. Heute sind es schätzungsweise nur noch ca. 200. Für diesen dramatischen Rückgang dürfte in erster Linie der viel zu geringe Reproduktionserfolg verantwortlich sein (0.2-0.4 flügge Junge pro Brutpaar und Jahr). Um den Bruterfolg auf ein populationserhaltendes Mass von ca. 0.8 Jungen pro Paar zu steigern, wurde bei einem Restbestand in der Zentralschweiz (10-25 Paare) ein Artenförderungsprogramm in Angriff genommen. In den Jahren 2004-2006 wurden alle Kiebitzgelege markiert und auf diese Weise von der Feldbearbeitung ausgespart. Dank der ausgezeichneten Zusammenarbeit mit den örtlichen Landwirten ging in dieser Zeit kein Kiebitzgelege bei landwirtschaftlichen Feldarbeiten verloren. Wenn allerdings die Bodenbearbeitung während der Gelegeproduktion erfolgte, wurden verhältnismässig viele Bruten aufgegeben. Hier kann es ratsam sein, die landwirtschaftliche Bearbeitung hinauszuzögern bis die Vögel mit dem Bebrüten des Vollgeleges begonnen haben. 2005 und 2006, nicht aber 2004, wurden Kiebitzgelege zusätzlich mit einem Elektrozaun, wie er bei Schafhaltern üblich ist, gegen Raubsäuger gesichert. Eingezäunt wurden in der Regel ganze Felder. In den so gesicherten Kulturen schlüpften 95 % der Gelege, in den nicht eingezäunten nur 39 %. 2006 wurden 81 Kiebitzküken besendert, um deren Überlebensraten und den Einfluss der Prädation zu untersuchen. Die Küken konnten den Elektrozaun ohne weiteres passieren (bodennahe Maschen 10x15 cm). Kükenverluste durch Prädation ereigneten sich überwiegend nachts (73 % aller Verluste) und außerhalb der Elektrozäune (87 % aller Verluste). Von 46 in der Nacht prädierten Küken stammte nur eines aus einer Elektro-Umzäunung. Kükenverluste, die durch tagaktive Prädatoren verursacht wurden, spielten eine untergeordnete Rolle (27 % aller Verluste). Sie traten innerhalb und außerhalb der Elektroumzäunungen in gleichem Umfang auf. Der Bruterfolg des Kiebitzes lag in 2005 bei einem bestandserhaltenden Wert von 0.8 Küken pro Paar. In 2006 führten hohe, prädationsbedingte Kükenverluste zu einem Bruterfolg von lediglich 0.25 Küken pro Paar

    Ecological and social effects on reproduction and local recruitment in the red-backed shrike

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    Numerous hypotheses have been proposed to explain variation in reproductive performance and local recruitment of animals. While most studies have examined the influence of one or a few social and ecological factors on fitness traits, comprehensive analyses jointly testing the relative importance of each of many factors are rare. We investigated how a multitude of environmental and social conditions simultaneously affected reproductive performance and local recruitment of the red-backed shrike Lanius collurio (L.). Specifically, we tested hypotheses relating to timing of breeding, parental quality, nest predation, nest site selection, territory quality, intraspecific density and weather. Using model selection procedures, predictions of each hypothesis were first analysed separately, before a full model was constructed including variables selected in the single-hypothesis tests. From 1988 to 1992, 50% of 332 first clutches produced at least one fledgling, while 38.7% of 111 replacement clutches were successful. Timing of breeding, nest site selection, predation pressure, territory quality and intraspecific density influenced nest success in the single-hypothesis tests. The full model revealed that nest success was negatively associated with laying date, intraspecific density, and year, while nest success increased with nest concealment. Number of fledglings per successful nest was only influenced by nest concealment: better-camouflaged nests produced more fledglings. Probability of local recruitment was related to timing of breeding, parental quality and territory quality in the single-hypothesis tests. The full models confirmed the important role of territory quality for recruitment probability. Our results suggest that reproductive performance, and particularly nest success, of the red-backed shrike is primarily affected by timing of breeding, nest site selection, and intraspecific density. This study highlights the importance of considering many factors at the same time, when trying to evaluate their relative contributions to fitness and life history evolutio

    Copperhead Madrigal

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    Soupbone Madrigal

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    p. 18

    Prioritising prevention strategies for patients in antiretroviral treatment programmes in resource-limited settings

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    Expanded access to antiretroviral therapy (ART) offers opportunities to strengthen HIV prevention in resource-limited settings. We invited 27 ART programmes from urban settings in Africa, Asia and South America to participate in a survey, with the aim to examine what preventive services had been integrated in ART programmes. Twenty-two programmes participated; eight (36%) from South Africa, two from Brazil, two from Zambia and one each from Argentina, India, Thailand, Botswana, Ivory Coast, Malawi, Morocco, Uganda and Zimbabwe and one occupational programme of a brewery company included five countries (Nigeria, Republic of Congo, Democratic Republic of Congo, Rwanda and Burundi). Twenty-one sites (96%) provided health education and social support, and 18 (82%) provided HIV testing and counselling. All sites encouraged disclosure of HIV infection to spouses and partners, but only 11 (50%) had a protocol for partner notification. Twenty-one sites (96%) supplied male condoms, seven (32%) female condoms and 20 (91%) provided prophylactic ART for the prevention of mother-to child transmission. Seven sites (33%) regularly screened for sexually transmitted infections (STI). Twelve sites (55%) were involved in activities aimed at women or adolescents, and 10 sites (46%) in activities aimed at serodiscordant couples. Stigma and discrimination, gender roles and funding constraints were perceived as the main obstacles to effective prevention in ART programmes. We conclude that preventive services in ART programmes in lower income countries focus on health education and the provision of social support and male condoms. Strategies that might be equally or more important in this setting, including partner notification, prompt diagnosis and treatment of STI and reduction of stigma in the community, have not been implemented widely

    Prof. Dr. Drs. h.c. hans STUBBE

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