David Crosby, a prominent figure of the free-spirited 1970s Laurel Canyon scene who helped bring folk-rock mainstream with both The Byrds and Crosby,

Stills & Nash, has died at 81. His publicist confirmed the artist's death to NPR; no cause of death was given at the time of this report. Crosby had long dealt with serious health problems,

including multiple heart attacks, diabetes and hepatitis C, for which he had a liver transplant in 1994. In spite of those challenges, the musician enjoyed a creative hot streak in recent years.

He added five solo albums to his catalog between 2014 and 2021, and toured frequently with two sets of collaborators, the Lighthouse Band (which featured Snarky Puppy bandleader Michael League) 

and the Sky Trails Band, featuring his son, James Raymond, on keyboards. Crosby's focus on touring stretched all the way back to his early professional days,

when he was a nomadic folk musician honing his performance skills on the road. In the late 1950s, Crosby started performing at coffeehouses in Santa Barbara, Calif.,

but soon began traveling around the U.S., popping up in southern Florida, Chicago and Boulder, Colo. Crosby also spent a formative period in Greenwich Village,

where he teamed up to play at the then-new Bitter End with Chicago musician Terry Callier. His long and successful solo career notwithstanding,

Crosby thrived on collaboration — a trait he discovered as a young child, after being mesmerized by a symphony orchestra performance.

"The idea of cooperative effort to make something bigger than any one person could ever do was stuck in my head," he wrote in his 1988 autobiography.

"That's why I love being a harmony singer, why I love being in a group."