To avoid enemy crafts, naval submarines will often run silently

, shutting down nonessential functions and cutting crew chatter. Now, an international team of researchers has found that Blainsville's beaked whales

also go into stealth mode to avoid being eaten by their mortal enemies, orcas

. While they normally click, buzz, and whistle to one another in the deep, the aquatic mammals stop all gab when they enter waters shallower than about 550 feet, presumably because killer whales typically hunt in shallow water. This is surprising considering that the beaked whales spend only 40 percent of their lives in the deeper waters—scientists expected that the animals would need frequent communication to maintain social ties. Makes you wonder: How often do the whales leave the deep to get away from all the gossiping? [Read more at BBC

.]

Image: NOAA