The effect of sheep (Ovis aries) presence on the abundance of ticks (Ixodes ricinus)
Hege H. Steigedal, Leif E. Loe, Lise Grøva and Atle Mysterud in Acta Agriculturae Scandinavica, Section A – Animal Science
Hege H. Steigedal, Leif E. Loe, Lise Grøva and Atle Mysterud
The distribution of ticks is increasing in many parts of the world, including Norway. It has been suggested that this is linked to climate change while the role of different land use practices appears less clear. Here, we investigate the variation in abundance of questing ticks on the west coast of Norway and relate this to the presence of sheep, a tick host that also modifies the landscape through grazing. We found that questing tick abundance was higher in areas without sheep, suggesting that sheep alter vegetation in turn reducing tick survival. However, we cannot exclude that other mechanisms may also lead to reduced abundance of questing ticks; sheep may negatively affect the local density of red deer which is an important alternative host. In any case, sheep farming may contribute to limiting the local abundance of questing ticks and related diseases.