DAVID BARON, CALL YOUR OFFICE: When Biking and Bears Don’t Mix. “The death of a ranger, Brad Treat, in 2016 was a wake-up call for grizzly bear biologists. Mr. Treat, an avid mountain biker, was zipping along at about 25 miles an hour through dense forest near Glacier National Park in the middle of a summer afternoon when he collided with a large male grizzly bear. . . . ‘I heard a thud and an “argh,”‘ the unnamed witness told investigators.”