A hydrophone streamer that includes several arrays of optical fiber pressure sensors. Each array consists of at least three sensors symmetrically disposed around the inside of the streamer skin to form a vertically-disposed array. Each sensor modulates a coherent light beam in accordance with the instantaneous ambient water pressure. The output signals of the sensors include an AC component due to seismic waves and a DC component due to hydrostatic pressure difference between the sensors of an array. Means are provided to resolve the AC and DC components to determine the arrival direction of the received seismic waves.