Mules have been helping maintain various national parks for over 100 years. Olympic National Park. Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. Five new mules at Olympic National Park in Washington State are ready for the busy tourist season. Murl, Cutti, Pip, Checkers, and Gopher join the park’s large working mule herd . Mules have helped maintain the trails in national parks since the early 1900s, and they continue to help monitor Olympic’s one million acres, 600 miles of trails , and 64 trailheads. Murl, Cutti, Pip, Checkers, and Gopher were named by the park staff and are a nod to the different native plants and animals found at the national park. The mules help trail crews in more wild areas of the park. Olympic National Park’s mule herd works from April through October and then spends the winter in a large pasture. Image: Olympic National Park.…