Whistling talent is genuinely impressive

I bought my cockatiel specifically because I read they were good whistlers. The reality surpassed my expectations. Within six months he had learned six distinct tunes including a passable rendition of Beethoven's Ode to Joy. He whistles for hours when content and the sound is actually pleasant rather than shrill. He is also gentle, easy to handle, and costs very little to keep well. Brilliant bird.