theHunter: Call of the Wild

Animals Scared is under Codex > Hunter > Hunting Profile.

This achievement seems to be a bit bugged. It doesn't seem to unlock for people at exactly 1,000 animals scared. People have reported that it unlocks once you scare 4,000 animals instead.

The best and most effective way to getting this is by driving around with the 4-Wheeler. You will notices that wherever you go, the animals will either be gone already or running. This works best on the Layton Lake map as there are far more animals.

To kill time, you may want to uncover every unmarked location on your map.

You can check how many scared animals you have somewhere in the codex, though if someone could tell me exactly where, I could add it to the solution.