WINNING STATUS OF REGENERATED-CLAWED MALES IN CONTESTS WITH ORIGINAL-CLAWED MALES IN AUSTRUCA PERPLEXA (BRACHYURA, OCYPODIDAE)

This study determines the winning status of regenerated-clawed males (regenerated males) in contests with original-clawed males (original males) in Austruca perplexa (H. Milne Edwards, 1852), and how they deal with original opponents. We observed that the numbers of regenerated and original winners were not different. The regenerated contestants, who were either burrow owners, or larger than their opponents, or avoided escalated contests (claw-interlock/fling), had the same chance of winning in comparison to their original opponents, and had a higher winning chance than regenerated contestants, who were either intruders, or smaller than their opponents, or did engage in escalated contests. Regenerated intruders tended to challenge opposite-handed opponents for avoiding claw-interlock (the risk of injury is high during claw-interlock), because claw-interlock is mechanically difficult between opposite-handed contestants. This study shows that regenerated contestants, who are either residents, or larger than opponents, or avoid fighting escalation, are able to compensate for the detrimental effect of regenerated claws during contests.