[The colonization of forested areas by Ixodes ricinus (Linné, 1758) in France: use of the roe deer, Capreolus capreolus (L. 1758) as a biological marker].

The roe-deer is a wild animal for which Ixodes ricinus has a particular fondness. Its territory is similar to that of the ticks and it is a species which is found throughout France yet which rarely leaves its territory. Given these conditions, a systematic parasitological examination of the ungulate can provide pertinent information concerning the forests inhabited by the tick. Since it is difficult to conduct a thorough examination of a large number of roe-deer over a limited space of time and on a large territory, the best solution is to examine the hind feet (hooves and tarsus) of the animal which are widely covered by the preimaginal stages of the tick. This biological material is easily available to the extent that the measurements of the animals are often used for game management. A preliminary study was conducted in Dordogne (southwestern France). Out of the 137 pairs of feet examined more than 50% carried the tick species (larvae or nymphs). The critical analysis of the results obtained throughout the investigation enables us to be more specific about the conditions of application of the advocated method.