Animal Ally is a gear perk that stops wild animals attacking you unless you provoke them first. It makes exploring Yara's wilderness much less hectic.
Crocodiles, jaguars and other predators stop jumping you on sight. You can travel through jungle and swamp without surprise fights breaking your stealth.
Wear one of the gear pieces that carry it: Hutia Tee, Trapper Vest. Each piece only takes one body slot, so plan around the other perks you want.
Very handy for stealth players and explorers. Hunters may prefer it off, since they want predators to come to them.