First evidence of attraction of adult river lamprey in the migratory phase to larval odour

Sexually immature, adult river lamprey Lampetra fluviatilis in the upstream migratory phase, were shown to be attracted to water conditioned with ammocoete larvae when tested using a two‐choice flume. Although preliminary, the data suggest that migrating adult river lamprey may be attracted to larval putative pheromone as recorded in sea lamprey Petromyzon marinus .