Impacts of semi-domesticated reindeer on structure of tundra and forest communities in Fennoscandia: a review

Abstract

Grazing and trampling by semi-domesticated reindeer are important factors controlling vegetation in northern Fennoscandia. In this article we review Nordic studies on the effects of reindeer on vegetation and animal communities. The studies have shown clear effects on vegetation, especially on Cladina lichen dominated sites. Cladina is the main forage of reindeer during winter and dominates climax vegetation in dry site types in the absence of reindeer. Reindeer can even affect galling and ground-dwelling invertebrates. Due to the special relationship between reindeer and Cladina majority of the research has concentrated on winter grazing on Cladina, but there are some studies of summer grazing which have also shown substantial changes in vegetation. Reindeer grazing increases richness and diversity of vegetation and invertebrate assemblages in most cases, but this influence depends on site type and grazing intensity. The enriching effect seems to be strongest at moderate grazing intensity.