Electrophysiological Responses of Three Tick Species1 to Carbon Dioxide in the Laboratory and Field1

Abstract

Olfactory perception to carbon dioxide gas was electrophysiologically investigated in Amblyomma americanum (L.), Amblyomma maculatum Koch, and Dermacentor variabilis (Say). Response time to carbon dioxide stimulation in females was of longer duration than in their conspecific males throughout all tests. Response times of females reached a peak at age 8–10 wk postmolt. Response times of males gradually decreased with age. Ticks preconditioned to low ambient carbon dioxide always produced response times of longer duration than ticks preconditioned to high ambient carbon dioxide. As preconditioning humidity increased, tick response time increased. Duration of tick response time to carbon dioxide at the temperature regimes tested was variable. Amblyomma americanum adults were selected for further study under field conditions to determine the efficacy of CO2 tick traps on attraction of ticks of various ages. A higher percentage of ticks 8–10 and 12–14 wk postmolt was retrapped.