The Everglades-coded region in GTA 6 is the most wildlife-packed biome we see in any official footage. Here's what's visible, and what the real-world ecology suggests.
See the wildlife list page for the full list, and the Everglades region guide for a tour of the region.
Confirmed in trailer footage
Alligators (separate article). Flamingos (separate article). Various waterbirds in flight. A wading bird that could be either a heron or an egret. Sound of insects - cicadas heard in the background of some swamp scenes.
Plausible based on real ecology
Florida panthers. Manatees in the connecting waterways. White-tailed deer. River otters. Turtles. Numerous species of fish (less noticeable but expected).
Snakes - python (a non-native invasive species in the real Everglades), water moccasin, rattlesnake. Whether GTA 6 has these would depend on Rockstar's animation budget and willingness to stomach low-to-the-ground threat models.
What the wildlife system implies
If the wetlands ship with even half of these plausible species, then GTA 6 has a wildlife system worth caring about. RDR2 raised the standard; the Everglades-coded ecosystem is where GTA 6 will most directly invite the comparison.
Hunting - covered on the hunting speculation page - is obviously the question that follows. It's unconfirmed for GTA 6.