Food availability and water temperature are two of the major factors that can affect patterns of activity and movement of stream-dwelling fish.  Individual fish within each species may respond differently to these factors depending on their size, social status, and environment.  The ways in which each fish responds to fluctuations in food availability and temperature may ultimately determine their survival.  We conducted an invertebrate drift depletion experiment in a small coastal stream near Dunedin on the South island of New Zealand.  The study ran from 21 February 2006 to 7 April 2006.  Our main objective was to determine how banded kokopu (Galaxias fasciatus Gray) movement patterns and diel activity change with experimentally reduced invertebrate drift.  There was no apparent affect on diel activity, but significantly more fish emigrated from drift depleted pools than from control pools.  These results suggest that banded kokopu respond to reductions in food availability by emigrating rather than by altering their diel activity patterns.