Comparison of novel and conventional methods of trapping ixodid ticks in the southeastern U.S.A

Abstract

Tick-borne disease surveillance and research rely on resource-effective methods for tick collection. This study compared the respective performances of several trapping methods in a mixed grassland-forest habitat in western Tennessee. To test for temporal differences in effectiveness, sites were sampled monthly (April-August 2013) using dry ice, dragging, flagging, sweep netting, carbon dioxide (CO2 ) dragging and CO2 flagging methods. To evaluate the effect of habitat on method effectiveness, four methods (dragging, CO2 dragging, CO2 flagging and dry ice) were compared in four habitat types (bottomland deciduous, upland deciduous, coniferous and grassland) in June 2014. In the temporal comparison, ticks were found to be most abundant in April and May, and there was a significant sampling period and method interaction, such that method effectiveness varied across sampling period. Sweep netting was significantly less effective than the other methods. In the habitat comparison, dry ice trap collections represented the most effective method in upland deciduous and coniferous habitats. Flagging using CO2 was significantly less effective than CO2 dragging and dragging in bottomland deciduous habitats. The success of the various collection methods did not differ significantly within grassland habitats. Overall, dry ice trapping and dragging were the most effective methods for tick collection across time and habitat.

Keywords: Amblyomma americanum; Amblyomma maculatum; Dermacentor variabilis; Ixodes scapularis; carbon dioxide; dragging; flagging; questing; trapping.