1st Place: Blacklegged ticks, Ixodes scapularis, sense and avoid ant-frequented areas

Monday, November 14, 2022

11:06 AM – 11:18 AM PT

Location: Vancouver Convention Centre, Meeting Room 205

Presenting Author(s)

Claire E. Gooding (she/her/hers)

Graduate Student
Simon Fraser University
Burnaby, British Columbia, Canada

Co-Author(s)

RG

Regine Gries

Simon Fraser University
Burnaby, British Columbia, Canada
GG

Gerhard Gries

Professor
Simon Fraser University
Burnaby, British Columbia, Canada

Blacklegged ticks, Ixodes scapularis, are obligatory blood feeders and transmit more disease-causing microbes than any other blood-feeding arthropod. Despite their reputation as blood-feeders, ticks spend most of their lifespan off hosts. Off-host ticks are highly susceptible to predation, particularly by ants, but the mechanisms underlying predator avoidance behavior have not yet been studied. Because foraging ants deposit semiochemicals to communicate with nestmates, and because blacklegged ticks have no defenses against ant predation, we tested the hypothesis that ticks avoid ant-frequented areas by sensing the ants’ semiochemical deposits. In two-choice still-air olfactometers, we show that semiochemical deposits of thatching ants, Formica rufa, deter adult female blacklegged ticks. The deterrent semiochemicals originate from both the poison gland and Dufour’s. Extracts of both glands combined, but not of either gland alone, proved deterrent to ticks.