When protests led by John DiLeonardo interrupted Long Island performances by the Cole Bros. Circus 10 years ago, the Malverne native thought his animal rights activism had reached its peak.

But it was just beginning.

DiLeonardo, 34, the founder of Long Island Orchestrating for Nature, or LION, was a lifelong Malvernite before moving to Riverhead last July.

LION, he said, remains closely associated with his hometown, where he was founded. “We are still very well connected at Malverne,” DiLeonardo said. “This is where we established our roots.”

Before LION was founded and helped shut down circus events, DiLeonardo attended Davison Avenue Middle School and later Howard T. Herber Middle School.

DiLeonardo’s early years in school, he said, spurred his first professional goal: becoming a school counselor or psychologist. This goal was motivated by the feeling that he and his friends were neglected by the school system.

“I wanted to help kids in their youth get on the right path,” DiLeonardo said, “or off the wrong path.”

He earned a degree in education from Sienna College in 2010. At that time, he recalls, he believed his calling was to serve others through education. But that was just one interpretation of a larger mission.

“I’ve always wanted to make this world a better place and have the biggest impact on the world possible,” DiLeonardo said. “Namely, I wanted to help the group that needed help the most.”

Catherine Grefig, who now lives in New Jersey, was DiLeonardo’s neighbor for 30 years in Malverne. She said she wasn’t shocked by her devotion to animals today. “Growing up with him and watching him now, you can see he was destined to do this job,” Grefig said.

“He was always looking out for people, younger or skinnier people…he was always a protector,” she said. “It was obvious for him to embark on this work.”

His goals changed, DiLeonardo said when a world religions class in Siena changed his life. There he discovered Jainism, whose followers are vegetarians. He described learning that Jain monks were waiting for nuts and berries to fall from the trees, determined not to harm the plant in any way.

“I was so inspired by that and surprised,” DiLeonardo recalled. “You wait for the berries to fall from the trees, and I can’t stop eating chicken. What’s wrong with me?”

This inspired him to learn how animals are raised for dairy and meat production. What he learned led him to become a vegetarian in 2007 and a vegan a year later. He encouraged others to do the same. “We all grew up eating animals, we all grew up going to the circus,” he said, “but when we know better, we should do better.”

Then, in August 2012, when, DiLeonardo said, he was still unsure if he considered himself an animal rights activist, he found himself protesting the Cole Bros. Circus in Oceanside with his friends. The result? The circus has lost tens of thousands of dollars in ticket sales from the protests, in which protesters told would-be attendees about the circus’ violations of animal welfare laws and showed them video footage of one of his animal trainers abusing and degrading elephants.

“They decided to spend their money elsewhere,” DiLeonardo said of the circus goers, “and it was very empowering.”

After that, he said, he and his Malverne friends created a Facebook page for LION and applied for nonprofit status in November 2012.

LION’s first major event once formed was to protest against the fur industry on Black Friday, which is marked annually by the animal rights movement as Fur Free Friday. Since then, DiLeonardo and the band have never looked back.

As he started working with people with special needs after college, he realized he would become an animal rights activist. “I knew my life was now calling for the animals,” he said.

He began taking classes at the Humane Society Academy, based in Maryland today, where he met a professor who was launching the first accredited anthropozoology program in the United States. DiLeonardo applied for and eventually earned a master’s degree in anthrozoology, also known as nonhuman animal studies.

He was recruited to speak at a 2014 animal welfare conference in California after a conference representative heard about local LION victories, such as stopping the slaughter of 600 geese in North Hempstead. He talked about being an activist while working full time, as he still worked for Innovative Resources for Independence, an organization that serves people with intellectual and developmental disabilities.

After the conference, there were job offers and DiLeonardo began to believe for the first time that he could make a living fighting for animal rights. He quickly applied and was hired by People for the Ethical Treatment of Animals, where his transition to full-time animal rights activist began in 2015.

He quit working for PETA last July to focus full-time on LION, and DiLeonardo now focuses on rescuing ducks and other animals across Long Island and spreading a message promoting animal rights. .

On January 25, he and other activists were arrested at the US Department of Health and Human Services building in Washington, where they were protesting taxpayer-funded experiments on monkeys. But that did not discourage him.

“I’m glad to be arrested for protesting…because I know we’re on the right side of history,” DiLeonardo said. “Hopefully it won’t be long before the people hurting these animals are the ones who get arrested, not the ones who shed light on it.”