Future prevention
Two things to do to stop this happening in future
1. Place a notice on the camera trigger mechanism (in English and the local language) reading
"I hereby assign all rights to any pictures or media created here by my actions to the owner of this camera and to fore go any future claim for payment other than reasonably incurred documented expenses. By triggering this mechanism I agree to these conditions."
2. Shoot the monkey.
That should do it.
Biting the hand that feeds IT
