Nope. It's absolute garbage, I'm afraid. A sound wave is a sound wave, and if it hits something such as a wall, then it will echo. It's possible that the frequencies of sound in a duck's quack aren't particularly high, and may not be easy to hear though. Additionally, most of the time, the only thing a quack might conceivable echo against is the water - almost everything else in it's environment will probably absorb sound.