Not All Drift Feeders Are Trout

Although the majority of drift-feeding fishes are cyprinids or other non-salmonid taxa, the majority of habitat selection models for drift feeders have been developed and tested with trout, charr, and salmon.  We describe the development and current status of the drift-feeder microhabitat selection model of Grossman et al. 2002.  This model has been validated for four cyprinid species in southern Appalachian streams.  The model relies on foraging success estimates at varying velocities and does not include physiological costs.  We discuss results of the model in light of current data on population dynamics of several species used to validate the model.  We also discuss the relevance of the model to foraging – habitat selection patterns of species where social behavior affects foraging success including both North American minnows and  kokopu (Galaxias spp.) in New Zealand.