Fish predation on the macrobenthos of tidal salt marsh pools

Abstract

A combination predator inclusion–exclusion cage was used to examine predation by sticklebacks (Gasterosteidae) on the macrobenthos of tidal salt marsh pools. Although there were fewer oligochaetes found in plots with fish than in plots without fish, this result is interpreted as a cage-produced artifact. Caged sticklebacks fed much more than uncaged fish elsewhere in the marsh. We propose that the enclosed fish, unable to reproduce inside the cage, had more time available to feed than free-living fish. There was no evidence to support the hypothesis that fish predation plays a significant role in structuring the macrobenthic community in the salt marsh pools.