Partner Control and Environmental Fouling in the Crayfish-Branchiobdellid Symbiosis

Previous research found that crayfish (Cambarus chasmodactylus) may be engaged in a cleaning mutualism with ectosymbiotic worms (Annelida: Branchiobdellidae), yet mechanisms for symbiosis establishment and maintenance remain unknown. In addition, it is unclear why a co-occurring crayfish species (Orconectes cristavarius) hosts almost no worms. The research in this thesis seeks to answer some of these questions by incorporating field surveys with laboratory and field experiments to assess the influence of both partner control behaviors and environmental fouling on the interaction between crayfish and branchiobdellid worms.