Fig. 1. Schematic of the experimental setup. The room of 4.2x3.2x3.2 m (lengthxwidthxheight) was covered with planar and pyramidal foam. Speaker devices contained target loudspeakers LS 1 to LS 4. The two-dimensional horizontal distance to the speaker row was 2.35 to 3.35 m, whereas the linear distance from the perch (owl position) to the speakers was 2.97 to 3.87 m (cf. Table 1). Background speakers (BS) provided masker noise. C1 to C4 are infrared cameras. Cameras C3 and C4 were mounted on the ceiling. Camera C1 was mounted at a height of 25 cm on the wall opposite the perch; camera C2 was placed at a height of 95 cm on the side wall. Tracker, DynaSight head tracking device. Landing positions of the owls as deviation (in cm) from the center of the target LS were plotted in a polar coordinate system as positive and negative x- and y-coordinates, respectively (see inset).