Depends on when/weather. Nemo is great for having a break in a dry, climate-controlled auditorium. They cut the length of the show post-Covid, and while it is still good, it has lost some of its emotional connection to the audience, IMHO. I also think the casting for Nemo's dad has been weak - at least the three times I've seen it this year. I do highly recommend this to avoid the rain or when in need of AC.
Feathered Friends is always nice to see, but it is outdoors and the seats are just benches without backs. They have played with the storyline a bit over the years, and the one right now makes sense. It's cute and I think many folks are surprised by how entertaining it is for a "bird' show. Whenever I have the time to squeeze this in, I always enjoy it. For me, this is a filler show. I don't start my day with a plan to see it - but if my timing works out, you can bet I will watch it.
Basically - both shows are good and worth seeing. I'd pick based on your location in the park, the weather, time until the show starts, other things you are trying to do, and what you feel like at the moment. You can easily get to one of them in a day!
