Is global warming making fish deaf?

Global warming could be causing fish deafness

New research is suggesting that ocean acidification is causing some fish to lose their hearing.

Scientists from universities in New Zealand and Australia have discovered that elevated levels of carbon dioxide in our oceans is changing the inner ears of fish, leading to hearing loss.

Sound plays a key role in the way thousands of species communicate, find mates, and locate suitable, safe places to live. When researchers measured what happened to the hearing of the Australasian snapper, a reef fish, when larvae develop in a more acidic ocean they found juvenile snapper were up to 10 times less sensitive to sound.

Many reef fish hatch in the open ocean, and the juvenile fish swim back to the reef to make their home, using sound cues to get there. The researchers discovered that the inner ear of the snapper is altered when the fish grow up in carbon-rich water, leading to a drop in low frequency hearing, potentially preventing juveniles from finding their way to the reefs and threatening their survival.