I think that it's not unreasonable for game wardens, and other officials who are preventing or investigating poaching to enter privately owned non-curtilage land for that purpose. Otherwise, all privately owned land would be open to poaching with essential impunity, and hunting/fishing laws don't only apply to public land.
A trail camera, however, is not in and of itself evidence of poaching, and officers should have zero rights to interfere with someone else's trail camera in any way. Neither should officers be allowed to set up their own trail cameras on private land (without permission from the property owner). If officers find a trail camera, they should seek to speak with its owner, either by contacting the property owner, or by leaving a business card with the camera and waiting for the owner to contact them (if they so choose).