Push it: death is a stronger motivator than sex during the sea lamprey spawning migration.

Session: Invasive Species (4)

John Hume, Michigan State University, [email protected]
Thomas Luhring, University of Nebraska-Lincoln, [email protected]
Michael Wagner, Michigan State University, [email protected]

Abstract

One hundred years after they established, sea lamprey (Petromyzon marinus) continue to plague the Great Lakes. Controlling their numbers relies on pesticides to kill larvae in stream sediments, but adults are susceptible to behavioural manipulation while migrating. Sea lamprey use semiochemicals when selecting spawning habitat, localizing mates, and avoiding predators. Push-pull tactics - where attractive and repellent semiochemicals used in concert guide pests toward traps - has proven successful in controlling certain insects. We tested the effectiveness of this tactic in a sea lamprey-infested river in northern Michigan by applying repellent (a conspecific alarm cue) and attractant (a sex pheromone) semiochemicals in a push-pull configuration, attempting to guide sea lamprey towards traps. We found that alarm cue manipulates sea lamprey distribution by “pushing” them towards target areas, leading to rates of encounter with traps sufficient to achieve trapping-for-control targets. We failed to find evidence that the sex pheromone acted in an additive or synergistic manner with alarm cue; neither encounter rates with traps, nor trap captures, improved with the addition of the attractant. Therefore, behavioural manipulation using alarm cue could be an effective and benign means to reduce reliance on pesticide application to control this devastating invasive species.

Twitter handle of presenter
@thatlampreyguy