Acoustic Pingers

Acoustic pingers serve as a marine mammal deterrent device in net fisheries by emitting a sound that can be detected within a certain distance of the net. Implementation of acoustic pingers in gillnet fisheries has become widespread over the last decade, especially in the northern Atlantic, where it is required by law in numerous fisheries. Since there is evidence that some small cetaceans can become habituated to the sound produced by pingers, pingers are most effective when both the frequency and timing of the sound is variable and occurs at random to prevent habituation. Overall effectiveness of pingers has differed depending on location and cetacean population affected, but in over a decade of studies they have proven to substantially decrease small cetacean bycatch rates in fixed net fisheries. This is important since fixed net fisheries account for the majority of small cetacean bycatch globally, with over 300,000 estimated to die each year in gillnets alone.