ZULANDT, Thomas J.; ZULANDT-SCHNEIDER, Rebecca A.; MOORE, Paul A.; Labortory for Sensory Ecology, Bowling Green State University; Labortory for Sensory Ecology, Bowling Green State University; Labortory for Sensory Ecology, Bowling Green State University: Observing agonistic interactions alters subsequent fighting dynamics and outcomes in the crayfish, Orconectes rusticus

In many species, social interactions play a key role in deciding resource allocation. Typically, the more dominant individual receives more or higher quality food, mates, and shelters. In crayfish, hierarchies and dominance structures are often organized by dyadic interactions. In natural habitats, crayfish are very gregarious, and agonistic interactions often take place with other crayfish in the vicinity. In these situations there is potential for observers to gain valuable information about potential future opponents. Thus, we were interested in examing the potential impact of observing agonistic interactions on the subsequent social behavior. We allowed “test” crayfish to observe either a) two size-matched crayfish fighting, b) two size-matched crayfish not fighting, c.) an empty tank control, or d.) a negative control. The “test” crayfish was then placed in a separate arena and fought against a naive size-matched opponent. These second interactions were analzed by an observer, blind to the treatment, for initiation, winner-loser, and temporal dynamics of escalation. Our results indicate crayfish that observed an interaction lost significantly more often to naive crayfish than crayfish in the other treatments. In addition, there were changes in the fight dynamics for crayfish that observed encounters. These results have implications for hierarchies and social behavior in natural settings where observation of interactions by a third crayfish is common.