Corresponding with a friend from civil rights work days in 1964, he asked me if I still do duck talk which he remembered me doing for kids. Here is my response to him:

I do duck talk now and then and if I practice I can get so good that I can articulate anything - l and r take time. Since you are into language, I'll continue a bit longer on this subject.

I can also do it out of either side of my mouth even at the same time so I can have conversations between two ducks or duets - and they sound like different ducks - but all this only if I practice which I don't. I don't like doing it because it's a little unpleasant so I've only gotten really good like this when there were kids around who kept urging me to do it. Also - some people find it disturbing, like nails on a blackboard.

I learned how to do it because there was an older kid who lived across the alley from us in Fort Worth who could do it and I really wanted to learn so every day as I walked home from school (2nd grade as I recall), I tried to do it until finally I could. It was fun to pop out with it at different times as I was growing up and I found it most successful with younger kids and girlfriends. I remember using a young, sad sounding duck voice with one girlfriend in high school when she was mad at me and her imploring, "Stop it! Stop it! I can't be mad at you when you talk like that!"

Answers.com: The original voice of Donald was Clarence "Ducky" Nash, who was succeeded after 50 years by Disney artist Tony Anselmo.

For close to 50 years, Clarence Nash gave voice to Donald Duck, one of Disney's most popular characters. A native of Oklahoma, Nash had a natural gift for imitating animals and as a young man would perform them as part of a tour on the Chautauqua circuit. In the early '30s, he landed in Southern California where he performed radio advertisements for a dairy. Walt Disney heard the ad and called Nash in for an audition. He hired Nash. After hearing him read a quacked-up version of a nursery rhyme one day, the excited Disney knew he had found the right voice for his foul-tempered new character, Donald. Nash voiced over 100 Donald Duck cartoons and even performed them in several languages, thanks to phonetically written scripts. He remained the sole voice of Donald until his death in 1985. Nash also became the second voice of Jiminy Cricket after his originator, Cliff Edwards, died. ~ Sandra Brennan, All Movie Guide

When Nash died, I got hold of the Disney people and offered my services. I was told that there were so many people at Disney who spoke Donald Duck that there was no need for them to look elsewhere. I offered to compete with any of them. I said that my duck talk was much easier to understand than Donald Duck but that I could sound like him too. Alas, my efforts were in vain. Thus my life has devolved since then into obscurity and despair.