Abstract
Ilyoplax pusilla has been known to exhibit a unique mudusing territorial behavior termed barricade building. Most of the barricade builders are large males that can pair with females, which suggests that the barricade is built by males to aid courtship. We conducted this study to clarify whether the barricade building improves mating success. Barricade abundance and waving frequency was highest in June, corresponding to the peak of male courtship behavior. Males that paired with females built barricades significantly more frequently than did neighboring males that did not pair with females. These results suggest that barricading in I. pusilla enhances in pair formation.
