Host seeking activity of ixodes ricinus ticks based on daily consecutive flagging samples

Abstract

The seasonality of I. ricinus was studied by three daily consecutive flaggings in four sites situated in an ecotone between a spruce forest and a peaty meadow, a spruce forest, a beech forest and a dense spruce forest. First day flagging samples represent the most commonly used method for description of tick seasonality. Since two consecutive flaggings remove ticks in the vegetation, third day flagging samples represent the number of ticks ascending into the vegetation, which was interpreted as being closely related to the size of the free living tick population. First day samples of nymphs were reasonably consistent with the typical bimodal seasonal pattern of activity (Gray, 1991). Third day samples showed a more stable seasonal development with no or only limited bimodality. The host seeking period or retention time in the vegetation, as defined by the ratio between first and third day samples differed within the season. The host seeking periods were found to be long in the spring, short in midsummer and intermediate in autumn. By analysing the host seeking period for dependency of weather parameters, it was found that host seeking periods primarily depend on relative humidity and solar radiation. No significant difference in tick abundance in third day samples could be related to weather conditions.