[User23]

What do ducks say in Russia? In America it's quack and in Germany it's kwak.

[SAI_Peregrinus → User23]

And if you ask a bird watcher, it's "Wait, what type of duck?"

[dgellow → User23]

In French: coin coin :)

No idea how to explain the pronunciation though ...

[desdiv → dgellow]

IPA: /kwɛ̃.kwɛ̃/

Here's a French speaker pronouncing it: https://youtu.be/Dtta-mW6Pro?t=15

[grenoire → dgellow]

Now I understand Uncle Scrooge!

[deanCommie → User23]

Квак :) Just like the Germans

[ivm → deanCommie]

But it's "krya" (кря-кря), "kva" is what frogs say.