Many species use conspecific chemical cueing to coordinate biological functions such as migration, reproduction, defense, and habitat selection. In this thesis, I hypothesized that conspecific chemical cueing could be used by American Eels as mechanisms for bidirectional migration coordination and danger avoidance as functions of cue concentration and life stage dependency. In chapter 1, I investigated conspecific chemical cueing in the youngest actively migratory life stage, glass eels, regarding inland migration coordination. I demonstrated conspecific glass eel washing affinity over a wide range of concentrations, characterized cue concentration preferences and differentiation capabilities, and observed no change in response during pigmentation into elvers. In chapter 2, I investigated conspecific chemical cueing in the oldest migratory life stage, silver eels, to help maintain aggregations during the downstream spawning migration and to avoid danger. I characterized their behavioral responses to both live and dead silver eel conspecific odors in a laboratory flume bioassay using multiple scoring metrics, but observed no significant responses to either cue. Combined, this thesis offers a survey of chemical ecology within and across life stages of the American Eel, supports conspecific chemical cueing as a likely mechanism for inland migration coordination in glass eels, and contributes useful information toward species management and restoration efforts.
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