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Zürich, Switzerland

Over 13 years, the local breeding population and breeding localities of Common Kingfishers Alcedo atthis were monitored along a 30.8 km river stretch at the Upper Rhine. The local breeding population varied between 5 and 7 pairs. No correlation was found between the size of the local population and the number of ice days in the previous winter. Kingfishers occupied repeatedly the same 10 breeding localities, some of them for over 13 consecutive years. Based on the high occupation rate of breeding sites, the study area appears to be an optimal habitat. The described situation contrasts with the general picture of a species with high fluctuation in numbers and constantly changing breeding sites. We attribute this to habitat features typical for rivers with buffered flood regimes. The conservation of these highly attractive, durable nest sites should have priority in species action plans. © 2015, ALA. All rights reserved. Source

Aye R.,Schweizer Vogelschutz SVS BirdLife Schweiz | Bernardi E.,University of Lausanne | Christen W.,Langendorfstrasse 42 | Horch P.,Schweizerische Vogelwarte | And 12 more authors.
Ornithologische Beobachter | Year: 2013

The Corn Bunting is classified as Vulnerable according to the Swiss Red List and a priority species for recovery programmes. Its population in Switzerland has been estimated at 400 to 600 pairs in the years 1993-1996. The objective of the present study was to establish an updated population estimate for the period 2009-2011 and to identify the core areas for the conservation of the species. We based our population estimate on monitoring projects existing in four areas with corn bunting populations and for the rest of Switzerland on casual observations collected by the Swiss Ornithological Institute. This procedure resulted in an estimate of 93 to 103 territories on average for the years 2009-2011. The species has disappeared from many areas and a decline of about 80 % since the mid-1990s has to be assumed. Species recovery should therefore be of high priority in the remaining populations and in areas with a high potential. The current core areas of the species are the Champagne genevoise, the Grosses Moos, the Klettgau and the region from Lake Neuchâtel to Lake Geneva. Source

Since 1993, farmers have to manage a minimum of 5 % (7 % since 1998) of their cropped farmland as so-called ecological compensation areas to enhance biodiversity. Additional governmental funding is provided since 2003 for improved connectivity (ÖQV-V programme) and quality (ÖQV-Q programme) of these areas. Based on large-scale breeding bird census data from 1988 and 2008, we tested for 164 boroughs (each approx. 1000 ha) and 1027 landscape plots (40-60 ha each) whether population change of target species in agrienvironment schemes (UZL-species) was related to the extent and quality of ecological compensation areas within plots. Species richness and population size of UZL-species decreased by 20 % between 1998 and 2008. UZL-species bound to arable land showed an even stronger population decline of 50 %. The decline in a plot was proportional to the initial value in 1988. Revealed by analysis of variance, species richness and size of the breeding population in a plot were weakly correlated with the area of ecological compensation areas that fulfilled the standard of ÖQV-Q. However, total area of ecological compensation areas correlated only weakly with species richness and no effect was found for ecological compensation areas fulfilling the standard of ÖQV-V. The bottom line is that the ÖQV programme did mitigate the overall decline in breeding bird populations only slightly. The limited effects of the ÖQV programme on target species are attributed to methodological and biological causes. From a biological perspective, the ÖQV programme failed so far because most ecological compensation areas don't seem to constitute functional habitats for target birds. To generate a positive effect, the programme should focus on ecological compensation areas according to the standards of ÖQV-Q and new types in appropriate sizes and spatial position should be promoted that are relevant for birds (micro-structures with stunted growth of vegetation, stubble fields, shortterm fallow land, grassland with incomplete vegetation cover). We propose a shift towards an effect-based payment system that rewards the actual effect on biodiversity rather than the current effort-based compensation. Source

We evaluated the effectiveness of refuges for waterbirds on the Greifensee intended to mitigate the effects of disturbance from water-based recreational activities on birds, before (1994-1997) and after the marking (1998-2009) of the bird refuges. Adult Great Crested Grebes preferably moved into protected zones during the breeding season, the number of young per family increased in protected zones and they preferred protected lakesides during the moulting season. Furthermore, the temporal pattern of the onset of breeding during years with high nest densities suggested that protected areas were high-quality habitats of primary quality for Great Crested Grebes. However, the establishment of refuges did not affect the position of their likely nest sites. The population size of important reedbed birds (Little Bittern Ixobrychus minutus, Savi's Warbler Locustella luscinioides) increased simultaneously with the implementation of protected areas, whereas other species showed no change. Moreover, the bird refuges enabled species conservation measures i.e. for Common Tern Sterna hirundo or Common Black-headed Gull Larus ridibundus. In contrast to expectations, waterbird numbers in winter were higher outside than inside the refuges, probably because Great Crested Grebes increased in numbers and progressively rested in the open water. Based on these findings the authors list several recommendations for the establishment of protected zones on lakes. Source

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