Individual and status recognition in the crayfish, Orconectes rusticus: The effects of urine release on fight dynamics

This study examined individual and status recognition in dyadic interaction s between crayfish and determines how blocking the release of urine, a know n source of chemical cues, may influence recognition. Behavioral characteri stics of agonistic interactions were compared between crayfish pairs that f ought each other previously (familiar) and pairs derived from individuals w ith past status history but no previous experience with one another (unfami liar). To address the role of urine born chemical cues in recognition, figh t dynamics were examined in urine blocked and non-blocked familiar and unfa miliar pairs. Our results indicate the existence of status recognition in crayfish as fir st fights were longer than second fights and the statistical interaction be tween fight number and familiar/unfamiliar treatment was similar. Urine cue s play a role in social recognition in that fights are longer and more inte nse when urine cues are absent than when urine cues are present. Communicat ion of behavioral state through urine appears to play an important role in the agonistic interactions of crayfish.