HABITS OF FIDDLER CRABS PEARSE. 



421 



to dart into his burrow, and if danger threatens he quickly retreats 

 to this refuge. If one of his fellows encroaches on his domain, how- 

 ever, he rushes forth and enters into fierce combat. Each crab makes 

 his hole the center from which his activities are conducted, and he 

 treats the approach of any intruder as an unfriendly act. 



Though combats between two males are most frequent, males some- 

 times fight with females, and members of the weaker sex not in- 

 frequently struggle with each other. If two males that differ 

 markedly in size fight, the larger combatant usually takes little 

 interest in the fight and soon makes off, even though he may be hotly 

 pursued by his smaller antagonist. "When a smaller fiddler trespasses 

 on a larger crab's territory, however, he is soon chased away. The 

 most spirited combats are between males of the same species. 



In fighting (fig. 6), the males face each other and often dance 

 about excitedly, at the same time frantically waving the small chela. 



p^Tr^i^j^i' 



Fig. 7. 



-PiDDLEKS DEFENDING THEIR BORROWS. 



Drawn by Tom Jones. 



The large chelae are locked together, like two men shaking hands, 

 and each contestant attempts to break off his opponent's claw by a 

 a sudden wrench. The strain is so great that when one of the 

 fighters loosens his hold rather than lose his claw, he is often thrown 

 backward into the air, sometimes as much as a meter. The writer 

 has never seen the great chela used as a club in fighting, as Alcock 

 (1892, p. 416) maintains, but it often serves as a shield to ward off 

 a thrust. If a male gets the worst of an encounter, he frequently 

 retreats into his burrow and giiards it by extending his claw from 

 the opening. (Fig. 7.) Sometimes one male catches another nap- 

 ping and enters his burrow. In such cases the owner waits nervously 

 about until the intruder comes out and then chases him away, or he 

 boldly goes down after the intruder with his large chela extended 

 before him and usually emerges soon after followed by the intruder. 



