A 100 x— 800 m section of the sand dune system at North Bull Island, Dublin Bay, Ireland, was surveyed for entomopathogenic nematodes (EPN) by baiting soil cores with Galleria mellonella in July and August of 2001 and 2002. Two species were found: Steinernema feltiae (2.5 and 3.2% of cores) and Heterorhabditis downesi (1.9 and 3.8% of cores in 2001 and 2002, respectively). In each year, two colour variants of the G. mellonella cadavers containing H. downesi were found: purple and yellow. In both 2001 and 2002, H. downesi was most prevalent in the front 20 m of the dune system. Steinernema feltiae occurrence generally increased with distance into the dunes. In 2002, H. downesi was recovered most often in sandy paths than any other habitat surveyed but there was no habitat differentiation for S. feltiae. Human traffic may be an important factor in the distribution of both EPN and their insect hosts on Bull Island.