Factors influencing the distribution and activity of Dermacentor reticulatus (F.) ticks in an anthropopressure-unaffected area in central-eastern Poland

Introduction and objectives. Despite the increasing prevalence and significant role of D. reticulatus in pathogen transmission, the factors influencing its distribution and activity are still poorly known. The paper presents for the first time a study of the D. reticulatus ecology in a protected area, in which the dependence of D. reticulatus occurrence and activity on the ecological habitat type is analysed. Materials and methods. Tick collection and environmental monitoring were conducted from March - November 2012 and 2014 in five ecologically-diverse habitats in the Polesie National Park of central-eastern Poland. Results. The study shows that the most beneficial habitats for D. reticulatus are provided by meadow ecosystems dominated by plants from the class Molinio-Arrhenatheretea: Poa pratensis, P. trivialis, Festuca rubra, F. pratensis, and Alopecurcus pratensis, as well as Carex sp. sedges (64.78% of the tick collections). Less favourable conditions are offered by the fresh habitat covered by deciduous forest with dominance of Betula sp., A. pratensis, and Carex sp. sedges (15.27%), in the wet habitat dominated by Alnus glutinosa and Urtica dioica (9.00%), Betula humilis, Salix sp., and Carex sp. (8.44%), and in the subcontinental hornbeam forest Tilio-Carpinetum with poor undergrowth (2.50%). D. reticulatus avoids wet habitats with bog birch Betuletum pubescientis communities and moist pine forest Molinio-Pineteum, as well as habitats dominated by heather Calluna vulgaris. Conclusions. The distribution and dynamics of the activity of adult D. reticulatus depends on the biological and geoclimatic conditions prevailing in tick habitats. The structure of the flora colonising a habitat may be an indicator of the presence of this tick species.