The herd is comprised of a mix of 30 goats, sheep and a donkey named Jackson, the Chicago Department of Aviation said. They will graze on the vegetation, including tall grasses, on 11.5 acres of land on the north side of O'Hare's airfield.
The program is part of the Sustainable Vegetation Management initiative, which is the first program of its kind at an airport in the U.S>
"For six summers, this program has provided sustenance to dozens of furry friends, as well as an environmentally - friendly alternative to keep areas around the airfield safe and properly maintained," said CDA Commissioner Jamie Rhee. "It's all part of our commitment to ensure our airports have a positive impact on their surrounding ecosystems as O'Hare grows in the years ahead."
Over the past six years, herds of sheep, goats, llamas, alpacas, burros and donkeys have helped maintain the green space near the O'Hare runways and support the ecosystem of the airfield while mitigating wildlife hazards to aircraft, the CDA said.