Scientist Ernest J. Harris, an internationally acclaimed pioneer in the eradication of crop-destroying fruit flies, who received the Congressional Gold Medal and many other honors during a long, scientifically and societally engaged life, died on Tuesday at his Kaneohe home, surrounded by his family.

A research entomologist with the U.S. Department of Agriculture Agricultural Research Service in Honolulu for more than 40 years until he retired in 2006, Harris was 89 and would have turned 90 on May 24. The cause of death was cancer, said his wife, Bettye Jo Harris.

In September, Harris added, her husband had felt strong enough to travel and give a presentation at the ARS National Agricultural Library in Beltsville, Md., where he was inducted into the ARS Science Hall of Fame.

“Our son Greg (who accompanied Harris) was practicing signing in case Ernie’s voice got too soft, but he didn’t have to use it,” Bettye Jo Harris said.

Harris, who earned his Ph.D. in entomology from the University of Hawaii at Manoa, and his fellow inductees had “become international leaders in their fields by thinking creatively and developing innovative strategies addressing some of the most significant challenges facing agriculture today,” ARS Administrator Chavonda Jacobs-Young said in a statement.

For Harris, the challenge was to end the rampant ruination of mangoes, avocados, papayas, apples, grapes and other crops caused by Oriental and Mediterranean fruit flies, and indeed, the approaches he developed have quashed outbreaks of the pest in Hawaii and other Pacific islands, California, Latin America and Africa.

In an interview with the Honolulu Star-Advertiser last year, when he received an Outstanding Alumnus Award from the University of Hawaii College of Tropical Agriculture and Human Resources, Harris described himself as an ecological entomologist who followed the principles of integrated pest management, using holistic, biological controls and turning to pesticides only as a last resort.

He said he was inspired as a child by his mother, whom he watched plucking moth larvae off vegetables in her garden on his parents’ Arkansas cotton farm. “She didn’t use any chemicals,” he remembered with a smile.

Longtime colleagues praised the breakthroughs Harris pioneered.

“Ernie worked on applying sterile-insect technologies originally developed for the Texas screw worm to the Oriental and Mediterranean fruit fly, irradiating and then releasing them,” said Roger Vargas, research entomologist at the USDA-ARS U.S. Pacific Basin Agricultural Research Center in Hilo.

Then, “He implemented the first eradication of fruit flies, using sterile fruit-fly releases in Guam and the Marianas Islands,” said Luc Leblanc, curator of the William F. Barr Entomological Museum at the University of Idaho, who first met Harris as a student at UH-Manoa in 1997.

Thanks to Harris’ efforts, the state of California successfully switched to using sterile fruit-fly releases in lieu of aerial spraying of pesticides such as malathion, Vargas noted.

“But his greatest love was the parasitoid wasp, fopius arisanus, the fruit flies’ natural predator,” which Harris and his team were the first to successfully breed in captivity, Vargas said. Harris has traveled throughout the world to teach agricultural scientists in other countries how to raise the parasite in large numbers in laboratories and tactically release them to eradicate fruit flies.

Harris’ third contribution, Vargas said, was the application of botanically derived chemicals to lure and annihilate male fruit flies. Because the chemicals are naturally occurring, they pose a lesser threat to humans and pets than synthetic compounds do, Vargas said.

The soft-spoken Harris was not only renowned for his scientific creativity and achievements but beloved for his kindness, humility and sense of social justice, said Alphonso Braggs, president of the Hawaii chapter of the National Association for the Advancement of Colored People, which in 2012 presented Harris with a lifetime achievement award.

“It’s a tremendous loss of a very, very humble genius,” Braggs said. “He was an icon in his professional field and he was a noble citizen, a long time NAACP member and supporter along with his wife, and certainly a wise counselor to myself when dealing with issues affecting diversity.”

After graduating from an all-black high school in Little Rock, Ark., during the era of segregation in the South, Harris joined the Marines, and went on in 1947 to attend the University of Arkansas at Pine Bluff on the GI bill. In 2016, he and other former members of the Montfort Point (North Carolina) Marines were awarded the Congressional Gold Medal for the work they did in integrating that branch of the service.

Braggs and other fraternity brothers (he and Harris belonged to Alpha Phi Alpha Fraternity) enjoyed bringing high school students and other young people to the Harris home. “We’d say, this man is one of the reasons you enjoy fruits and vegetables from around the globe being so readily available, and the kids’d kinda perk up,” Braggs said.

“He was a wonderful, kind man and he loved Hawaii. There’s such a racial mixture. I think that’s why he found Hawaii so comfortable,” Vargas said.

The Harris family also lived in Tunisia and Morocco from 1969-1972 while Harris did fruit-fly research for USDA-ARS, and Harris, a car aficionado, bought a BMW in Germany that he shipped back to Hawaii. But as an ecologist, he refrained from driving it much, starting with the fuel crisis of the 1970s, Bettye Jo Harris said.

“He’d just walk up to Kam Highway and catch the bus to UH every day and would walk to downtown to get the bus back home,” she said. “That’s probably why he was able to go on so long.”

Until 2016, Harris continued to conduct research and publish in scientific journals in collaboration with Vargas and Leblanc.

Leblanc called Harris earlier this month to announce an early birthday surprise: He had just discovered several new species of fruit fly, and “the most spectacular- looking one, I decided to name it after Ernie.”

Although not yet official, its name will be Bactrocera ernesti. “He was thrilled, he was very happy. He was tired, but still very sharp.”

In addition to his wife, Harris is survived by daughter Tanya Harris, sons Gregory and Mark, grandson Malachi, brothers Robert and Lewis, and sisters Cindy Wimes and Myra Preyer.

A memorial service will be held at 10:30 a.m. April 7 at St. Christopher Episcopal Church in Kailua.