BILLINGS, Mont. (AP) — Yellowstone National Park Superintendent Dan Wenk plans to retire next March 30, ending a 44-year career with the National Park Service.

"I've had an amazing career with the National Park Service," Wenk said in a statement Friday. "It is an honor and a privilege to preserve national park resources and provide incredible visitor experiences, and I'm not done yet. I'm in the midst of several important projects that I will finish before I depart to ensure the smoothest transition for Yellowstone."

He wants to see some park bison that have not been exposed to brucellosis to be relocated to the Fort Peck Indian Reservation in northeastern Montana, work on developing a long-term visitor use management plan, negotiate concessions contracts and work with park staff to improve the workplace culture.

Wenk has been superintendent of Yellowstone park since 2011, where he manages more than 3,400 square miles (8,900 square kilometers) of land, a staff of 800 and annual budget of more than $60 million. Yellowstone has seen more than 4 million visitors in each of the past three years.

He began his career with the park service as a landscape architect in 1975. He was superintendent of Mount Rushmore National Monument for 16 years, beginning in 1985. In 2001 he was appointed the director of the Denver Service Center, which is the park service's central office with responsibility for planning, design and construction.

Wenk served as deputy director of operations for the National Park Service from 2007 through 2011, serving as acting director of the agency for nine months in 2009