I have an Eskie, they are known for being barky (and quite honestly there are some Saturdays when Ginger drives me crazy), but generally speaking she is a pretty quiet girl (even my neighbors tell me that ). Here is what worked with both her and my first girl. When she barks, get up and go over to her (assuming she is looking out a window, if she is looking at you, you won't need to get up). Tell her "shhh" the noise should make her tilt her head (if it doesn't make some kind of sucking sound, that should make her alert on the sound). Immediately tell her good girl. Then if you can, make the sound before she barks again when she looks tell her good girl. Do this everytime she barks for a couple of days. After that you should be able to stay seated and tell her "shhh" or whatever sound worked and she will stop barking and run to you for praise. Then after a week or so, she will just "shhh" when you tell her. Until the next squirrel runs in front of the window to make her bark. It will take a while until he/she learns what he/she should or shouldn't bark at, but at least it is a good start. Good Luck, I think Corgis are natural vocalists, too.

(Sorry, I realize that Vallis is a boy, but I was thinking of what I did with my girls when I wrote this that is why it all says "her" and "she".)