Electric Fish in the Wild (Gabon Rainforest, West Africa)

Again, this data is provided by Carl Hopkins. This is a brief example of recordings acquired by sticking a pair of electrodes into a river in the Gabon rainforest in West Africa. Three distinct fish are visible at three distinct frequencies even though their spike amplitudes may overlap. This is an illustration of how peak frequency display can be applied in the wild to rapidly detect signal sources. It also illustrates how smaller amplitude signals may present a noisy response in terms of the peak frequency parameter.

In this data set, the fish labeled Fish 2 swims quite a distance from the electrode and the peak frequency can no longer be discerned by g-PRIME. The other two fish stay at relatively constant distances with fixed frequency discharges.

Raw Data Files

• HOPKINS2007_04_27_1519_BB06_004.wav - 30 second recording from an electrode placed into a river in Gabon, West Africa.

Illustrating the energy density (size) of EODs in the recording. Signal size is proportional to distance from the recording element. 6 seconds after the electrode is inserted into the water, fish 2 swims away from the element.<.b>

Three distinct frequency levels for the fish are shown. At the 6 second mark, fish 2's spike gets small enough that low frequency content in the recording begins to register as the peak frequency in the detected event.