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Results from the monitoring programs of the Swiss Ornithological Institute show that the breeding populations of several forest species for which deadwood is an important habitat element (black woodpecker, great spotted woodpecker, middle spotted woodpecker, lesser spotted woodpecker, green woodpecker, three-toed woodpecker as well as crested tit, willow tit and Eurasian tree creeper) have increased in the period 1990 to 2008, although not to the same extent in all species. At the same time the white-backed woodpecker extended its range in eastern Switzerland. The Swiss National Forest Inventory shows an increase in the amount of deadwood in forests for the same period. For all the mentioned species, with the exception of green and middle spotted woodpecker, the growing availability of deadwood is likely to be the most important factor explaining this population increase.

On behalf of the Federal Office for the Environment (FOEN), the Swiss College for Agriculture established the basis to foster oak species in Switzerland. For this, the growth areas of three oak species, common oak (Quercus robur), sessile oak (Q. petraea) and pubescent oak (Q. pubescens) were assessed throughout the entire country. The assessment was based on their physiological potential, their natural growth area and on the appearance of the middle spotted woodpecker. In addition, the older mixed oak stands were surveyed. These fundamental data were collected with a geographical information system and analyzed for each canton. Altogether, approximately one-fourth of the Swiss forest area is suitable for oak. The natural oak growth area covers however 38 500 ha only. About 19 000 ha of forest are populated by the middle spotted woodpecker and extended older mixed oak forests are found on approximately 24 500 ha. According to the applied evaluation matrix, the greatest potential for fostering oak species lies in eight cantons: Aargau, Zürich, Solothurn, Thurgau, Vaud, BaselLandschaft, Ticino and Schaffhausen.

From 1997–2003, forest management measures in favour of the vulnerable middle spotted woodpecker were conducted in an oak-hornbeam forest in northern Switzerland. In this study,we examine the consequences of these measures on population size and location of breeding cavities of middle spotted and great spotted woodpeckers. We found that population sizes of both species remained stable despite considerable forestry action taken in old oaks stands of vital importance for these woodpeckers. In areas where the two management measures «coppice-with-standards» and «thinning of coppicewith-standards stands» were applied, no differences in the number of breeding cavities of both species immediately before and after management intervention measures could be found. However, the proportion of breeding cavities of the great spotted woodpecker increased in old oak stands which were not subjected to management measures, while middle spotted woodpeckers used such stands as expected from their availability. We conclude that the two forest management measures are, at least on the short run, appropriate to the ecological requirements of the two woodpecker species.

The middle-spotted-woodpecker Dendrocopos medius, which was deemed to have disappeared from the littoral of Neuchâtel,is a species in full expansion today, particularly in the Bois du Devens (MULHAUSER & BLANT en prép.). Without differentiated silvicultural interventions-i.e. differentiated according to area-today this region would be dominated largely by the beech. The article presents the evolution of the forest Bois du Devens, the development of silvicultural practice during the 20th century and its effect on the expansion of the middlespotted-woodpecker. The analysis of the silviculture practised in this forest since 1920, fleshed out with the numerical basis of the silvicultural inventories, provides confirmation of the dependence of the middle-spotted-woodpecker on oaks of major dimensions, with a preference for highly fertile habitats and underlines the importance of mature forest stands. Such heterogeneous stands are rich in microstructures, cavity trees,big trees, trees that accomplish their full life cycle, as well as entire crowns that are left on the ground after trees have been cut.

A targeted nurturing of oak in the canton of Argovia goes against the natural development of forest stands where the dominant, naturally occurring species is beech. Because of this,afforestation with oak is both work intensive and costly and is therefore concentrated on sites where silvicultural, economical and ecological aspects have been taken into account. With the help of a simple model showing areas where, above all,oak is nurtured, comprehensively mapped forest stands were classed according to competitiveness and correlated to thermal levels, that represent an important site factor for oak. One important aspect surrounding the issue is the preservation of genetic resources and an adequate supply of appropriate seed from chosen autochthonal, indigenous oak stands. In addition,the endangered population of middle spotted woodpecker,which is tied to widespread sites of aged oak-rich deciduous stands, should be fostered. Taking ecological priorities into account a possible area to nurture oak has been demarcated in the Fricktal.