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5> I have seen people use fire crackers or the sound to scare them

We have tried this. But this is a temporary solution, They give up the area for a few hours or a day. The next day they will come again.

Oh that would be a challenge to spray the trees though the boundary walls maybe
So another technique which some people use is to have a baboon. They would call a guy with a baboon .
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2> He would tie it at places where the monkeys used 2 come and they would give up the territory and move away. Some residential areas adopt this practice collectively. This works but not sure how viable it is for you to implement

3> Some science students used the idea to make a mannequin baboon with pre recorded sound to scare away monkeys from their college
I am not sure how effective that was

4>
But it is known that monkeys leave the area if there is a baboon in the vicinity
Another thing worth exploring is the ultrasonic sounds to repel monkeys. it can be tried for sure

If u r ok experimenting with sounds check this


read the comments first and stay at a safe distance. there are many sound sources available

also check this


This is just for a general idea not asking u to buy
May be if we can get the sound it can be played from an old mobile or music player with speakers attached

See, I have gone through many Youtube videos, which also include the ultrasound technique... Monkeys can hear even 50kHz sound.

But for me, it has to be affordable and cost-effective in the first place.