Larval Sea Lampreys (<i>Petromyzon marinus</i>) Do Not Emigrate from a Risky Habitat Under Semi-natural Conditions

Abstract

Sea Lamprey (Petromyzon marinus), invaded the upper Great Lakes in the early 20th century, precipitating abrupt declines ina number of native fish species. A recently proposed alternative method for the behavioural manipulation of Sea Lamprey populations is the use of conspecific damage-released alarm and predator cues as potential repellents. We examined whether larval Sea Lamprey (Petromyzon marinus) ammocoetes can be manipulated to emigrate from an area by labeling their habitat “risky” with the regular release of chemosensory alarm cues over several days. in a semi-natural laboratory environment, we exposed eight replicate groups of eight ammocoetes twice a day, for 7 days, to deionized water (control), ammocoete whole-body extract (damage-released alarm cue), and 2-phenylethylamine HCl (predator cue). None of the experimental stimuli induced emigration from the experimental arena. This approach does not hold any promise for ammocoete behavioural manipulation in the context of a Sea Lamprey integrated management program.