An award-winning Twin Cities pediatrician, on his yearly camping trip to the Black Hills with his wife and who owed his life to a liver transplant a year ago, crashed his motorcycle into a tree and died, authorities said.

Dr. Ernest W. Swihart Jr., 71, of Minnetonka, was killed Thursday in the wreck at the entrance to Pactola Reservoir, according to the South Dakota Highway Patrol.

Swihart was heading down a hill, "entered a curve and locked the brakes on his motorcycle, which caused him to lose control, enter the ditch and collide with a tree," the patrol said in a statement.

Swihart had ridden out from his campsite. His wife, Karen, waited for his return, which never occurred, according to the couple's family. The patrol said he was wearing his helmet.

Ernest Swihart was a behavioral pediatrician in Minnetonka with South Lake Pediatrics, which he helped found in 1974. He also was on the clinical faculty at the University of Minnesota.

In 1997, he won a Minnesota Book Award for co-authoring "The Manipulative Child." In 2013, he received the U's Department of Pediatrics Homer Venters Award. He appeared on ABC-TV's "Nightline" in 2011 to discuss the use of medication for children with attention deficit hyperactivity disorder.

On Sept. 22, 2013, Ernest Swihart was a liver transplant recipient after his hepatitis -- more specifically, nonalcoholic steatohepatitis -- was diagnosed two years earlier, according to his CaringBridge web page.

Paul Walsh • 612-673-4482