Mudballing revisited: Further investigations into the constructionbehaviour of male Uca tangeri

摘要

Male and female Uca tangeri (the only fiddler crab species to inhabit Europe) construct mudballs from mud excavated from within their burrows. Individual males placed similar patterns of mudballs each low tide, suggesting that there is some degree of stereotypy. When mudballs were experimentally moved further from the burrow or closer to it, males only repositioned those that were moved closer, placing them further away again. However, males did not replace mudballs that had been experimentally destroyed at the end of the mudballing phase when they had started to court females. In binary presentation tests, females showed no significant differences in response to mudballs made from different types of mud, or different numbers of mudballs. These results are consistent with earlier findings that male mudballs function as territory boundaries. However, we provide evidence that male mudballs have no function in female attraction, contrasting with previous studies.