Standing on a hill in Utah's Zion National Park, volunteers saw a herd of bighorn sheep quickly scatter in the distance last May. Baby sheep became separated from their parents as the herd of endangered animals ran in various directions.
What were they running from? A drone.
Apparently, a remote controlled drone had flown too close the herd causing the frightened commotion, according to the US National Park Service. This was one of many incidents that pushed the government agency to lay down the law about drone use in national parks. Last month, the service said it was issuing a temporary policy memorandum to prohibit unmanned aerial vehicles in the country's 401 national parks, which cover 84 million acres of public lands and waterways.
"We have serious concerns about the negative impact that flying unmanned aircraft is having in parks, so we are prohibiting their use until we can determine the most appropriate policy that will protect park resources and provide all visitors with a rich experience," National Park Service director Jonathan B. Jarvis said in a statement.
As the federal government has taken steps to ban drones in parks, states are also limiting unmanned aerial vehicles. Colorado's Garden of the Gods public park doesn't allow drones, nor does California's Monterey Bay National Marine Sanctuary.
The Monterey Bay sanctuary issued a statement last month saying flying unmanned aerial vehicles above or around the coastal waters is strictly forbidden because of disturbances to wildlife like seals, sea otters, seabirds, and shorebirds.
"Appearing suddenly [drones] can cause disturbance through sight, sound and movement," Monterey Bay National Marine Sanctuary superintendent Paul Michel said in a statement. "Wildlife often react by fleeing quickly, or if they remain behind, stay on high alert to guard against a return of the perceived threat. Such disturbances can create stress and can significantly affect an animal's health, particularly those that are pregnant or raising young."
Several national parks, like Mount Rushmore, the Grand Canyon, and Yosemite, had already moved forward on drone bans before the National Park Service's memorandum last month. In May, officials overseeing Yosemite grounded all drone use. They said unmanned aerial vehicles disrupt the park's natural landscape, interfere with visitors' experience, and have negative impacts on local wildlife like the peregrine falcons that nest on cliff walls.
The Federal Aviation Administration has long forbidden individual's use of drones -- although, it's been slowly loosening its stance. Last November, the agency released a report that cautiously said drone flying in certain situations might be possible, such as when farmers monitor their crops. And last month, the FAA said it may let some movie studios use drones when filming and gave its first commercial drone permit to BP energy corporation to monitor its oil pipelines in Alaska.
As for Zion National Park, rangers said the increased presence of drones zooming up slot canyons and filming the bighorn sheep caused the park to institute a ban. People caught flying the unmanned aerial vehicles in the park can get up to six months in prison and a $5,000 fine.
"I am sure most people who fly drones have no desire to harm wildlife or endanger our other visitors. Many may not even know that it is illegal to fly a drone here at Zion," park superintendent Jim Milestone said in a statement. "We hope that by educating the public about the reasons behind the restrictions, we will increase their understanding and compliance and help to protect the park."