The number of salmon aquaculture sites in the Bay of Fundy has increased over the past ten years. An unknown proportion of these sites are using acoustic harassment devices (AHDs) to deter seals from approaching salmon cages. A preliminary suvey of AHD use at salmon aquaculture sites in the Quoddy Region and Grand Manan Island, NB, was conducted between 17 August and 7 September 1996. In the Quoddy Region, 46% of aquaculture sites were using some form of AHD during daylight hours. In the Grand Manan area, 22% of aquaculture sites surveyed during the day were using AHDs. An evening survey of four sites in the Quoddy Region revealed that one AHD was activated only during evening hours, indicating our daytime survey data underestimates total AHD use. Three different forms of AHDs (10 kHz peak signal, 15 kHz peak signal, and a multi-frequency signal) were identified. The level of noise pollution associated with these devices may negatively impact marine mammal populations, including the threatened harbour porpoise (Phocoena phocoena), which use these regions on a seasonal or annual basis.