Social Hierarchies and shelter preference within Orconectes virilis populations.

Abstract

Dominance hierarchy in regards to shelter preference was studied using the virile crayfish (Orconectes virilis). Dominance was determined in groups of six individuals, then placed in an enclosure with three treatments of shelter distribution—three to three, four to two, and five to one ratios were used. Data suggested that crayfish distribute themselves among shelters based upon the density of nearby shelters, rather than by the previously established dominance hierarchy. Within the five to one shelter distribution, crayfish generally assorted themselves within hierarchy with regards to shelter distance, with one exception. Individuals of epsilon dominance ranking selected shelters nearest to the alpha ranked crayfish. This behavior suggests that the volatile dominance position of lower-ranked crayfish may cause some individuals to seek safety and higher proportion of resources through submission and proximity to dominant crayfish.