If you spot Peggy Harris while out and about, ask her for a whistle.

There’s a good chance that the energetic 85-year-old will gladly assume the posture of a power vocalist. Then, while gracefully curving and lifting her arms, she’ll pucker up and belt out a popular tune in a formidable bird-like trill.

“When someone asks me to perform, well, I jump on that like a dog on a bone,” Harris said. “I never say no when someone says: ‘Give me a whistle.’”

Since Harris moved to Hawaii more than four decades ago with her husband and four children, she has performed free whistling concerts in venues such as the Japanese Cultural Center of Hawai‘i, Shriners Hospital for Children, the Hale Koa Hotel and at multiple schools and veterans’ homes.

She discovered what she calls her “God-given talent” while growing up in Stedman, N.C., a small town outside Fayetteville.

As a child, Harris said, “I loved the ground my mother walked on. I was just tied to her apron.” While her mother sewed clothes for the family, “I’d sit by the sewing machine and just talk a mile a minute. … To get rid of me, she’d say, ‘Peggy, please go outside and whistle for me, I just want to hear you whistle.’”

Harris complied, whistling for her family’s enjoyment until they encouraged her to perform on a larger stage.

During her senior year of high school in 1950, she performed “When Day is Done” at a school talent show, singing the first verse and whistling the rest. After the show, she was approached by the manager of the largest department store in Fayetteville, who asked her to whistle for a fashion show.

“The president of the Rotary Club asked me to perform at a dinner show, too. Then a friend of the family asked if I’d whistle at their wedding reception, and I just thought, ‘Oh Lord, I am on my way to Hollywood.’”

After graduating from high school, Harris wanted to skip college and pursue a concert-whistling career. Her mother opposed the idea, and Harris attended a junior college near home. She whistled for a college glee club, but had to stand behind the curtain during performances.

“In those times,” she said, “it wasn’t ladylike to hear a girl pucker up and blow.”

Years later, Harris would whistle tunes for military wives during her husband’s two tours in Vietnam. She still performs regularly at the Oahu Veterans Center.

After moving to the islands in 1974, Harris worked as a substitute teacher at Makakilo Elementary School for 21 years.

At her husband’s request, she recorded and released her first album in 2009, “Peggy Harris Shares Her Gift of Whistling.” It features her versions of “The Lord’s Prayer” and “My Impossible Dream.” One hundred copies were made, which she gave away to friends and fans, some of whom had been asking her to record an album for a long time.

Although she’s now midway through her ninth decade, Harris is determined to remain young at heart. With happy-go-lucky optimism, she said, “Some people might say, ‘Oh, I’m 85, time to start acting old,’ but nope, not me.”

As a symbol of her upbeat outlook, she wears a glittering butterfly pendant. “You’ll never see me without a butterfly on my shoulder,” Harris said. “Butterflies mean new beginnings, and every day is a new beginning with me.”

As a registered organ donor, Harris said when the time comes, she’ll be honored to leave behind her powerful set of lungs. But her daily focus is on staying busy with volunteer work, enjoying weekly lunches with friends and, of course, performing, all of which keep her feeling young.

Harris plans to record a second album, which will feature “Wind Beneath My Wings.”

Meanwhile, she continues to perform at senior homes around the island and in the annual Kapolei Chorale Christmas Concert held at the Salvation Army Kroc Center.

Harris fasts before concerts, which helps her breathing. Ten hours prior to every performance, she consumes nothing but water and protein shakes. While performing, the motions of her arms follow the pattern of her breathing — she draws them inward while inhaling and extends them outward while holding notes and exhaling.

But even without a moment of preparation, Harris is happy to whistle a tune for a passer-by who may recognize her — or her shoulder-top butterfly — while she’s out and about, whether she’s shopping at Nordstrom or Costco or running an errand at the post office.

“Whistling always gets me in a good mood,” she said. “If I feel myself sinking, I put on some music and start whistling, and, honey, I feel young as ever.”