Not only do cod "speak" to each other, but they have "regional fish accents"—kind of like the aquatic version of a southern drawl—and that could be bad news for fish-and-chips lovers, Wired reports. According to the Boston Globe, marine biologist Steve Simpson recently started a two-year project to study the sounds surrounding cod. Cod "speak" by vibrating their swim bladders, but the noises they make vary based on where their breeding grounds are located. For example, US cod make a "deep thumping sound," while cod in Norway make a "higher-pitched sound, with a long growl," USA Today reports. Similar "regional dialects" have been detected in birds and various mammals, including, obviously, humans.
The problem is that rising ocean temperatures are forcing cod north, and they're bumping up against groups with different accents. Simpson says this could hurt their ability to successfully breed, the Telegraph reports. Male cod use sounds to convince females to release their eggs. That process would be difficult if they can't understand each other. But that's not the only problem. Noise from boats and other man-made sources could be making it harder for the cod to hear each other. "We may find that the ‘gossip’ essential to their society is being drowned out," Wired quotes Simpson as saying. "If we value our fish stocks—or our Friday night fish supper—we need to understand this.” (The "holy grail" of ornamental fish is disappearing.)