At higher elevations I sometimes employ a UV filter. Split or graduated density filters, which reduce the brightness of the sky relative to the ground, are quite useful. Since I take a lot of telephoto shots, a very solid tripod is indispensable and accounts, to the chagrin of my companions, for almost half the total weight of my photographic equipment. I use a Bogen with a universal ball head, which doubles as a candlestick, microphone stand, and emergency tent pole. When using telephoto lenses, I fill stuff sacks with rocks and drape them over the camera and tripod to add mass and stability.
All photographic equipment is subject to horrendous abuse.
In transit, I pack it in layers of clothing and shoes. Vibration from trucks bouncing over rough roads, or the flapping saddlebags of a runaway mule, are particularly deleterious to cameras. I pad all camera cases and bags with closed cell foam from old sleeping pads for shock absorbtion. In the jungle, waterproof bags designed for use in whitewater rafting, are useful, but care should be taken to let equipment breathe . In the field it is essential to have your camera available for use at a moments notice, since some of the best images are captured under unanticipated, or even emergency, conditions.