It's actually fairly common for birds to get motion sickness. Next time you take him for a ride, cover his travel cage with a dark blanket. If they can't see, they usually won't get ill. Just be sure it's not too hot and he can breathe and all. Weird that this is a thing, right? LOL I wouldn't have thought this was common but it is. Good luck!
It could be. Try avoid feeding a pet a few hours before the car ride to avoid this.
If you are concerned it could be something else just keep an eye on him. I don't think you have anything to worry about.
I hope this helps!
My macaw vomited in the car, is it motion sickness?
