Do you dislike restaurants where noise drowns out dinner? Seems that fish don't like a din with dinner either. Because loud sounds, for example from whizzing speedboats, distract them, and apparently impair their predatory skills. So suggests a study in the journal Public Library of Science ONE. [Julia Purser and Andy Radford, "Acoustic noise induces attention shifts and reduces foraging performance in three-spined sticklebacks (Gasterosteus aculeatus)"]
Researchers took 12 fish tanks, and killed the gurgling filter sound to mimic the quiet of a calm lake. Then they immersed a speaker in each tank. And watched three-spined stickleback fish hunt water fleas, to the accompaniment of either white noise calibrated to match the noise level of speedboats or a silent track as a control.
Fish in each trial ultimately gobbled up the same numbers of prey. But the sticklebacks in noisy tanks spent more time attacking what's not for dinner, like bits of algae. And they often captured water fleas only to spit them out again.
The researchers say the buzz of boats may divert attention from the hunt—causing fish to waste more time and energy chasing prey. Such inefficiency could contribute to declines in their numbers. And unlike us, fish can't ask the restaurant manager to turn the volume down as they dine.
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