Noise pollution in the ocean damages cephalopods’ auditory structures
Pollution is not limited to toxic chemicals in the air and water—light pollution in urban environments, for example, has been shown to affect the mating rituals of some birds. Research has also shown that noise pollution in the oceans alters the behavior and communication of marine life such as dolphins and whales that depend on sound for daily activities. And a recent study published in Frontiers in Ecology and the Environment (e-View) indicates that noise pollution could have a more widespread impact on the ocean environment.
That is, Michel André from the Technical University of Catalonia in Barcelona and colleagues found that low frequency, high intensity sound in the oceans causes massive damage to the auditory structures of cephalopods, like squid and octopus. As Andy Coghlan described today in New Scientist, “It’s not just dolphins and whales that suffer from the noise of shipping, sonar and oil prospecting. Experiments on squid, cuttlefish and octopuses show that their balancing organs are so badly damaged by sound similar to submarine noise pollution that they become practically immobile. The consequences seem permanent.”
Specifically, André and colleagues examined the statocysts—fluid-filled sacs responsible for determining balance and positioning in cephalopods—of cuttlefish, squid and octopus that had been exposed to low frequency sound bursts. The researchers found that all of the squid experienced damage to the hair cells inside the statocysts (compared to cephalopods that were not exposed to the sound), and those that were exposed to longer durations of the sound showed large lesions in their statocysts.
André, M., Solé, M., Lenoir, M., Durfort, M., Quero, C., Mas, A., Lombarte, A., van der Schaar, M., López-Bejar, M., Morell, M., Zaugg, S., & Houégnigan, L. (2011). Low-frequency sounds induce acoustic trauma in cephalopods Frontiers in Ecology and the Environment DOI: 10.1890/100124