Mountain forests and ungulates in the European Alps


Wild ungulates were rare or absent in the Italian Alps at the beginning of this century. In the past almost all forests were used for the farming of cattle, sheep and goats. In the southern part of the Alps the intensive use of forests for domestic animals has declined in this century and particularly during the last few decades. Simultaneously, after the Second World War, wild ungulates (especially red deer and roe deer) increased in number and expanded their range.
The coexistence between forest and wild ungulates, especially red deer, was made easier in the past by the availability of the valley bottoms and the outer areas of the valley for wintering. Nowadays, the natural migration of the red deer to bottoms of the valleys or to the plains outside the mountain range is prevented by the presence of roads and land settlements. In addition, ski areas and cross-country skiing inside valleys prevent the use of some areas as a winter range and represent a significant disturbance in winter. As a result of this situation the red deer and other ungulates are forced to winter in substitute areas which are not particularly suitable.
Mountain forests are more exposed to damage than plain forest. In these forests regeneration is only possible every few years, depending on the climate and on seed production. As a consequence, natural regeneration is divided into cohorts with a few years of difference between each. In the upper mountain and subalpine levels the early growth of the trees is very slow and young trees need an average period of 20-60 years (varying among the sites and the species) to reach a height of 150 cm. That means that the trees are exposed to browsing for a long period and a few years of overpopulation or a few severe winters, when animal populations are concentrated in a limited area, are enough to endanger a recruitment process of decades. Wild ungulates, although part of natural ecosystems, can cause damage when their densities are too high and also change the structure and dynamics of the forest as a result of the intensity and the selectivity of damage.
In all the Italian Alps the foresters apply naturalistic silviculture, using only natural regeneration and practicing single tree or small group selection in the mountain level and small group selection in the subalpine level. Forest management activities have a significant impact on wildlife but naturalistic silviculture offers two important benefits in the case of ungulates: good resistance to game damage owing to the abundance and the density of regeneration, and good ungulate habitat. Ungulate damage appears to influence silvicultural practices. In order to manage the problem effectively foresters need to be able to relate an observed effect on the tree seedlings and saplings to the effect the damage will have on the silvicultural system in terms of prospects of regeneration, changes of mixture and reduction in yield.

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