Sticklebacks show consistent prey-share hierarchies within but not between patchy and sequential prey distributions

Abstract

When animals compete, hierarchies can emerge. If the outcome of competition under different conditions is dependent upon different sets of attributes, then we may expect to see hierarchies that are domain-specific, rather than domain general. We tested this idea by comparing prey share hierarchies within shoals of sticklebacks Gasterosteus aculeatus as they foraged for patchily-distributed or for drifting prey. We found that prey share was correlated across pairs of patch- and pairs of drift-foraging trials, but not between the two conditions, suggesting that separate repeatable but independent prey share hierarchies arise for each for each type of prey distribution. We discuss possible underlying mechanisms and ecological implications of this finding.