Spillningsinventering för bestämning av älgbetesbelastning på ungskog

Abstract: In the 1980’s the moose population in Sweden grew explosively due to big changes in the silviculture with clear cuttings instead of single-tree selection. Clear cuttings brought big areas of young forest and therefore a lot of fodder in one place. Since this change, the discussion about how to manage the moose population has grown into a very big problem. Forest owners think that the population needs to be strongly reduced because of all the damage that is done to the young forest when the moose seeks its food, and the economic losses because of that. At the same time hunters think that the moose population should be maintained at a level that allows a yearly yield, so that they can continue hunting on a yearly basis, which is a large part of the Swedish culture. Both forest owners and hunters are starting to understand that they must begin to cooperate in order to come up with a long lasting solution. Nowadays the attempt is to detect which amount of forest damage that is economically acceptable and on that basis determine how many moose that can be allowed in our forests. Independently on how many moose we should have, we must know have many we do have to be able to manage the population. To find this out, inventories of the moose population needs to be done. One of the most efficient ways of doing this is by droppings inventory and this has also proven to be the most economical way. We know approximately how many times a moose leave droppings every day and by counting all the droppings in one area we then, roughly, know how many moose there are. Most damage done by moose is during wintertime when the food situation is at its worst state. Young forests are then exposed because they are one of the few places moose can find fodder wintertime, due to its accessible branches and tops. Earlier studies show that grazing pressure on young forests are about five times higher than in other forests this time of the year. So to make this all a little more complex, we also need to know how big areas of young forests these moose have access to, to be able to foresee the damages that the moose can do. This is where this study comes in, for the purpose of it is to be the initial element in the quest of enlarging knowledge concerning the quantity and quality of fodder from young forests. Another reason for this study to be done, is for the sake of having a more recent study within the subject of grazing pressure on young forests and the final purpose is to find out if the results from droppings inventory can be used to produce statistically significant key figures that can be used to find out what the grazing pressure in one area really looks like. To be able to find this out, comparisons have been done to the earlier studies that say that the grazing pressure approximately would be about five times higher in young forests.