摘要

The dominance hierarchies of freshwater crayfish have been extensively researched internationally and are associated with the division of limited resources, such as food, shelter and space. However, dominance hierarchies in the endemic, New Zealand freshwater crayfish (koura) Paranephrops zealandicus (White) have not been determined empirically. This paper has two aims: (1) to determine whether there is a size-based dominance hierarchy amongst koura competing for spatial refugia, and (2) determine whether agonistic interactions decrease as the size disparity between competing individuals increases. To address these aims we paired wild koura in aquaria with a single shelter and measured the number of approaches, attacks, retreats and escapes made by each individual. In 26 of 31 trials (84%), the larger individual was dominant, indicating that a size-based dominance hierarchy does exist within koura. Aggressive behaviour in paired individuals decreased as the size disparity increased.

  • 出版日期2011-6