As with many old and rapidly aging do-dads in the park, the flying fish probably finally broke and instead of fixing or rebuilding the fish management decided to go the easy route (like the fort, the waterfall and the fire in the cabin) and just remove it altogether.
The log walled entryway to Frontierland I think its days are numbered; if you go into the ATM area there and look closely at the wood it is infested with termites. I noticed it one day while trying to talk on the phone and attempting to deaden the ambient sound so I stood against that wall in there and I had termites in my face!
I liked the information and old pictures of Nature's Wonderland. I know many of the animals on Big Thunder are leftover survivors of NW.
As a film historian and lover of Westerns the Calamity Jane reference with the Golden Horseshoe is great, I'll have to pull out that DVD and check that out. The petrified stump I'm surprised some have misse dit as it is right out there, kinda hard to miss and now you won't be able to miss it. When I was a kid we would always get pictures with it and I remember thinking I was clever by theorizing it must be the oldest item in the park. Second oldest must be the oldest steam train which if I recall dates back to the 1890s.
Oh and I LOVE the story about floating the logs on the Rivers of America to get them "downriver" to the building site of Fort Wilderness.