Have you looked at any "TRAILCAMERAS"?
Hunters use them for seeing what game is around.
I have several,some take still pics and video and they are triggered by motion so when nothing is there it's not running.
Some take infrared in the nightime so no light scares off game.
The quality of pics will be determined by what you are willing to spend of course.
Some take long clips some short it depends what you set them up for.
You will be restricted by the size of the storage,most use SD cards.
Some have solar panels to keep batteries charged up.
Most hunters et them up where they can be checked and changed as needed.
ALL are weatherproof,I have left mine out in some extreme weather,from rainstorms to blizzards,one I believe was out more than it was home in its lifetime.
All mine have been "tested" by bears and survived for the most part.
I'm sure your monkeys will investigate the cameras.
Mine are only used on still pics...
Not sure what model cam this is but it appears to be pretty good quality.
Pentax 18-55mm,Pentax 50-200mm,Sigma 17-70mm,Sigma 70-300mm, Sigma 50-500mm