It's kind of hard to explain gramatically why it's fly instead of flew.. especially since I haven't had an english class in 3 years. It's just one of those things that I just know. Flew does not sound right at all to me. Also, I double checked the sentence with Microsoft Word just now, and they also say that the word should be fly.
As for the old forest creatures, I'm pretty sure there are a few more that have missing punctuation and capitalization, but it just seems too minor to drag myself all the way over to the forums to post everytime. If no one else has posted the mistakes, then it probably doesn't matter to them either, or they are mindless clickers, like I am guilty of being a great deal of the time..
But yeah.. I'm not trying to nit-pick.. just here to help..