The production of salicylihalamide A by the marine sponge Haliclona sp. was investigated. Samples of the two morphologies (green and brown) were collected from four locations covering approximately 1,200 km of coastline. Temporal variation between winter and summer was also examined at Bremer Bay. Chemical profiling by using liquid chromatography coupled with ultra violet detection and mass spectrometry showed that salicylihalamide A was produced only by the green morphology. Salicylihalamide A concentration was significantly correlated to water temperature but not to the size or depth of the sponge. Salicylihalamide A concentration was found to differ significantly among locations (Bremer Bay 13.5 mu g g(-1), Hamelin Bay 11 mu g g(-1), Rottnest Island 9.9 mu g g(-1), and Jurien Bay 8.5 mu g g(-1)) partially accounted for by the influence of water temperature. A difference between seasons was also observed in Bremer Bay (summer concentration of 13.5 mu g g(-1) vs. winter concentration of 8.2 mu g g(-1)). Environmental and physiological factors appear to be important in the production of salicylihalamide A by the green morphology. Additionally, the brown morphology does not produce salicylihalamide A, thus adding to the evidence that this morphology may be a different species.