Wild Ride by Liam O'Donnell, illustrated by Michael Deas

From chapters.ca:
Devin, Nadia, and Marcus are on their way to visit their environmentalist parents who are working to stop a logging company from clear- cutting a remote valley. When their plane crashes and the pilot is killed, the kids are left to survive in the wild with Wiley, a government bureaucrat, who is the only other passenger on the plane. Learning to build a shelter and make a fire in the woods, they discover that Wiley is working with the logging company and will do anything to stop the secret getting out. On the run and in mortal danger, the three must outrun Wiley, escape a raging forest fire and outwit a hungry grizzly bear to make it to safety.