Burmese Pythons aren't native to the Everglades, and they're only there (for the most part) because of people who have bought them as pets but released them into the wild because they got too big/didn't want them/etc. So, since they're not native to the Everglades and their numbers are rising quickly, they're causing the numbers of other wildlife to go down because they're eating all of them.
tl;dr- Burmese Pythons eat all the native wildlife in the Everglades.