<p><span style="font-weight: 400;">Many of the oysters’ life activities are cued by sounds. </span><a href="http://www.epoc.u-bordeaux.fr/index.php?lang=en&page=fiche_permanents&id=jcmassab"><span style="font-weight: 400;">Jean-Charles Massabuau</span></a><span style="font-weight: 400;">, one of the scientists involved in the study, said sounds and vibrations</span><span style="font-weight: 400;"> cue activities such as feeding, spawning or protective movements. “Our results show that in shallow waters, they must be able to hear breaking waves and water currents,” he said. This enables them to open to receive food during the arrival of a tide. It also helps them to avoid becoming food for other creatures. “Lobsters or fish, which feed on young oysters, produce sounds in the oyster hearing range, if they’re close enough.”</span></p><p><div data-conversation-spotlight=""></div></p><p><span style="font-weight: 400;">Oysters also spawn during thunderstorms. The sound of the storm is thought to trigger synchronized spawning activity. </span><a href="https://www.pbs.org/newshour/science/earless-oysters-can-hear-noise-pollution-and-arent-pleased"><span style="font-weight: 400;">Massabuau likens the closing action</span></a><span style="font-weight: 400;"> the oysters exhibit when exposed to loud sounds to the reflexive jolting action people make when startled.</span></p><p><span style="font-weight: 400;">Human-generated sounds, such as those made by huge container ships, offshore oil drilling, and explosives, “muddle the normal oyster sound landscape,” says Massabuau, who says human-generated sounds may cause the oysters to open up at the wrong time, for instance, responding to ship noises as if they were tidal sounds. The noise could also mask the sound of predators, or cause the oysters to close during feeding times. </span></p><p><span style="font-weight: 400;">“If mussels and oysters keep their shells closed because of the vibration from human-produced noise, then they may be unable to feed, leading to starvation, poor reproduction and other impacts,” said </span><a href="http://www.hull.ac.uk/Faculties/staff-profiles/Professor-Mike-Elliott.aspx"><span style="font-weight: 400;">Mike Elliott</span></a><span style="font-weight: 400;">, a University of Hull, UK, researcher whose own studies previously discovered that </span><a href="http://dx.doi.org/10.1121/2.0000324"><span style="font-weight: 400;">hermit crabs and marine mussels can sense sound vibrations</span></a><span style="font-weight: 400;">.</span></p><p><span style="font-weight: 400;">Ocean sounds have been found to have a devastating effect on more complex sea creatures. Andre’s earlier studies found that the loud sounds produced by the shipping and oil drilling industries turned the delicate balancing organs of squid, cuttlefish, and octopuses into pulp, rendering them unable to move properly or orientate themselves, leading to their imminent death. “For the first time we are seeing the effects of noise pollution on species that apparently have no use for sound,” </span><a href="https://www.newscientist.com/article/dn20364-shipping-noise-pulps-organs-of-squid-and-octopuses/"><span style="font-weight: 400;">he said. “We were shocked by the magnitude of the trauma.”</span></a></p><p></p><p><a href="https://www.scientificamerican.com/article/does-military-sonar-kill/"><span style="font-weight: 400;">Underwater sonar, such as those used by the US Navy, also has a devastating effect on sea life</span></a><span style="font-weight: 400;">. Whales, dolphins, and porpoises are injured and killed by sonar systems, which generate a sound of up to 235 decibels that can range as slow-moving waves up to 300 miles without losing much strength. (The loudest rock concert is around 180 decibels.)</span></p><p><span style="font-weight: 400;">In a desperate attempt to escape the painful and destructive impact of sonar, whales will swim hundreds of miles, rapidly change their depth (sometimes leading to bleeding from the eyes and ears), and even beach themselves. Many mass beaching events are preceded by military exercises involving explosives or sonar.</span></p><p><span style="font-weight: 400;">If humans are unconcerned about the fate of other animals, they might at least take consideration of the impact on the availability of one of their favorite delicacies. Wild oyster populations have been declining due to a number of factors, including pollution, warming waters, and even hurricanes. </span><a href="http://jacksonville.com/news/metro/2017-10-16/progress-coming-not-fast-reopening-duval-county-oyster-beds"><span style="font-weight: 400;">In Florida</span></a><span style="font-weight: 400;">, oyster beds have been closed in recent years because polluted water flushes the oyster beds with dangerous bacteria blooms, rendering them unsafe to eat. </span></p><p><span style="font-weight: 400;">Texas oysters, which have already been severely impacted by Hurricane Ike and the Deepwater Oil Spill in the past 10 years, also took a direct hit from Hurricane Harvey.</span></p><p><span style="font-weight: 400;">“From the standpoint of oysters, the biggest impact is probably going to be felt in the Galveston Bay area,” Lance Robinson, Deputy Division Director for Coastal Fisheries, says. “We certainly have seen mortalities of oyster reefs in the bay approaching 100 percent.”</span></p><p><span style="font-weight: 400;">These delicate creatures are facing increasingly tough conditions. The least we could do is turn the volume down.</span></p>
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