Despite what you may have heard, walruses do NOT say “Koo Koo Ka Choo” although you wouldn’t know it by the frequency at which that phrase is posted to Twitter. In actuality, a walrus sounds a little like “Chewbacca” from Star Wars or more accurately, the other way around. Walrus make a variety of grunting and whistling sounds, they do NOT bark like sea lions. Hear and see for yourself
Here’s a “soundboard” of various walrus sounds as well. Now you know!
http://www.soundboard.com/sb/Walrus_sounds.aspx