Woodpeckers as indicators of natural forest ecosystems

WeißrückenspechtCentral Europe is an old cultural landscape in which practically no area has been able to preserve its natural state. The far-reaching anthropogenic changes also affect the remaining type of forest strongly, that it is not known exactly what they look like under natural conditions. Largely unchanged forests can only be found on small remaining areas in some higher mountains and in the far east of Central Europe. Naturally, around 95% of Germany’s area would be covered with forest. The European beech or Common Beech (Fagus sylvatica) would probably occupy around 70% of the country’s area as the predominant tree species in western Germany. Due to their specific diet and the associated high degree of specialization, woodpeckers are particularly suitable as indicators for near-natural forest ecosystems. From this, the anthropogenic changes in the forests can be derived. The wealth of woodpecker species in Europe reflects quite well the strength of human influence on the originally forested landscapes. In almost all European countries, the clade of woodpeckers would probably be represented with 7 to 8 species if there would be still larger natural forest areas. The sensitivity of the woodpecker to habitat changes and thus its suitability as an ecological indicator increases with the degree of specialization and ranges from the “habitat generalist” Great Spotted Woodpecker (Dendrocopos major) to the highly endangered White-backed Woodpecker (Dendrocopos leucotos) and Three-toed Woodpecker (Picoides tridactylus).

Several studies, among others in the Bialowieza forest show that the White-backed Woodpecker is the most sensitive species of woodpeckers. It can only find optimal conditions in strictly protected reserves, mostly in national parks. In the past 80 years, three quarters of the White-backed Woodpecker habitat in the Bialowieza forest has been lost as a result of forestry management. The full dynamics of the natural forest only unfold in useless protected areas. This dynamic is necessary in order to provide the White-backed Woodpecker and the community of xylobiont insects from which it lives, the necessary proportion of dead wood. The lack of dead wood structures is the most significant difference between virgin forests and near-natural economic forests. An optimal deadwood stock of 5 to 10% of mature trees is never reached in the economic forests. In addition to the amount of dead wood, the quality of the dead wood is particularly important. As food specialists, many – especially large – beetles are dependent on deadwood of large dimensions, as this provides the larvae with a constant indoor climate over several years of development. With natural management, a large part of the woodpecker community including the old-wood-specialist Middle Spotted Woodpecker (Dendrocopos medius) can be preserved. The White-backed Woodpecker as a target species for the protection of largely natural deciduous forest ecosystems, on the other hand, requires the designation of total reserves without any management.

The Great Spotted Woodpecker, on the other hand, is probably the most professional user of blacksmiths. Sometimes natural cracks or niches in trees are processed so that they fit exactly for a certain food object. Or – sure as in this case – the woodpecker takes advantage of the forest fire and chisels the appropriate holes directly into the weakened tree. Especially now in winter, conifer seeds are the main food for the Great Spotted Woodpecker.

The Great Spotted Woodpecker is the carpenter of the forests. Its most important tool is the powerful chisel beak. He uses it to hammer caves into trunks and thick branches. There he can then pick out beetles and larvae or even put on an anvil to chop up nuts, fruits and, above all, pine, Spruce (Picea) cones or Larch (Larix) cones. Although the Great Spotted Woodpecker has a very varied diet with significant seasonal changes, an important food source consists on the one hand of larvae of wood beetles (Cerambycidae, Scolytidae, and Buprestidae) and on the other hand of plant food. Some plant material is rich in fat, especially in the form of softwood cones and in the form of various nuts. This type of food production is gaining in importance as winter feed. The Great Spotted Woodpecker can therefore be found in a variety of habitats.

To cope with the growing demand for top shots of the species of the Palearctic, Bird-Lens is keen to enrich the range of pictures of birds not only in the western Palearctic. Trips around the home range or to remote places to capture images were very successful. The nice image of the blog is only a first impression, what you will find in the gallery in the “Picture Shop” very soon. Just give bird-lens.com a message, if www.bird-lens.com could serve you with an image needed before the new pictures are online.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.