Cameras: get the hunting type with flash. These cameras are used by hunters to shoot pictures of the paths the animals take. They are battery run and batteries will last a week. There will be a flash, so encase the camera to protect it, or raise it high in the air. To add, these cameras are digital, provide a date/time stamp, and are motion-detected activated.
Simple enough.
At the ORV park, we have several setup. We have more containers than cameras. Once the fense destroyers saw that they were being pictured, they haven't come back. Though they now do take pop shots with their guns. Thus the use of extra containers to protect the cameras. I think the sheriff has a good lead onto the perpetrators as we haven't had any incidents since last summer.