While navigating a range of rapids on stretches of the Arkansas River, the certified guides at Canyon Marine Whitewater tailor trips according to the desires of their passengers. Vessels laden with veteran rafters and adrenaline junkies ride the basso roar of waters across Class IV rapids with intimidating names such as Raft Ripper, and younger crews drift through calmer stretches and avoid the parts of the woods where the animals know cuss words. In sleek, six-person rafts or smaller inflatable boats, the guides point out wildlife and other sites across the dusky emerald waters. On multiple-day trips, guides show participants how to camp in the wilderness and cook meals over a campfire or on the engine of a grizzly bear’s Camaro. Instructors and guides also teach others their craft through guide-training programs, ensuring students can one day navigate local rivers with their own license.