The major form of transportation within the Grand Canyon is causing major erosion problems on the trails, the National Park Service reported Sunday.
Mules carry approximately 26 tourists a day to the bottom of the canyon, but their weight and their hard hooves are damaging the trails, The Arizona Republic reported.
The Park Service is working on an environmental assessment of the mule operations.
Environmental Protection Specialist Rachel Stanton — who is studying budgets, public-opinion comments and erosion studies — told the newspaper the mules can be maintained, but at a price.
“Maintaining the trails uses a lot of our resources, meaning people and money and energy,” she said.
In addition, her report must comply with the National Environmental Policy Act of 1969 which mandates federal agencies consider environmental values.
Stanton said people who walk the trails don’t do the damage mules do. She said foot traffic tends to compact the surface of the trails.
The National Park Service isn’t ready to pull mules off the trails, but it considering suspending tourist rides and using mules only to carry equipment to the maintenance crews, the newspaper said.