Diurnal and Seasonal Activity of Unfed Adults of Rhipicephalus appendiculatus (Acarina: Ixodidae) in Relation to Some Intrinsic and Extrinsic Factors—III

Abstract

Groups of Rhipicephalus appendiculatus adults were prepared at three levels of hydration (100, 85 and 65%) and placed in small field enclosures. Some of the ticks were broadcast over the vegetation, while others were confined in nylon gauze bags and placed at soil level. Weight changes in the bagged ticks were monitored for 3 consecutive days by twice-daily weighing. Observations were made in the hot dry season, rainy season and the cool dry season. During the hot dry season there was a progressive loss in weight over the observation period, as during the night the ticks could not fully replace the water lost by day. In the rainy season there was an initial rapid uptake of water at night by the dehydrated groups and any weight losses during the day were easily replaced at night. In the cool dry season water losses were slight, and though ticks regained water at night, neither of the dehydrated groups became 100% hydrated during the period of observation.