Der Einfluß des Elbebibers auf Waldbestände und forstwirtschaftliche Konsequenzen

Abstract

During the years 1991 to 1993 the species, Number, and diameter of trees cut by the beaver were recorded in five study areas in the Middle Elbe region near Wittenberg. So damages caused by the beaver in forest should be quantified. It could be shown that beavers prefer Populus, Betula and Cornus species but are also be able to change their feeding habitats in dependence of the local supply. They mainly cut trees of a lower diameter with an average of 3,45 cm. In old woods without much undergrowth they couse barking damages on old trunks. However, the total damage remains relatively low. lt fluctuated between 0,11 and 4,07 % with an annual amount of 1.8 to 12,6 fm per beaver Settlement. By testing commercial repellents used in agriculture and forestry a deterrent effect on the beaver habitats can be drawn: 1. Forest clearing directly to the bank should be avoided. 2. To prevent damages softwood strips of low diameters and a breadth of about 30m should be kept or plantetd along the bank of the water. 3. In areas seriously affected by the beaver single future trunks should be selected and protected individually. 4. Timber trees or forestry border along waters should be left to spontaneous succession.