Your premise makes sense from the angle that the animals lose their fear of man when man cannot threaten them.
I spent a few days last week at a racoon infested campground armed with a super soaker full of ammonia. One wiff was all they needed to turn tail and stay away.
"a super soaker full of ammonia" Full-quill NH3? Anhydrous ammonia?
I'd high-tail it into the next state.
Just kidding, but you meant "weak ammonia solution" in water.
Like the "hydrogen peroxide" you buy in the drug store...it is 3% H2O2 and 97% water.
--Boris