Keeper of the Wild By Joe Paddock. This is the first biography of wilderness preservationist Ernest Oberholtzer, environmnetal pioneer and explorer and caretaker of Minnesota's and Ontario's Boundary Waters region. Oberholtzer fought long and hard to preserve the wilderness for the canoers and campers who followed in his tracks. His story is fascinating to those who love to paddle here, and it continues to inspire wilderness activists to this day. 322 pages, hardcover.