The nation's biggest trend in volunteer service comes with its own apparent contradiction.

At a time when people are busier than ever, more of them are volunteering for multiple causes, parceling out a few hours here and there each week in an effort to spread good will.

But ask Paulo Maurin why he offered 11 hours a week to three organizations, even as he worked toward his doctorate at the University of Hawai'i, and his answer isn't complicated:

It was fun.

"What I like best is teaching," said Maurin, who leads groups of elementary school children through the Waikiki Aquarium. "It's a phenomenal thing. Sometimes with tours, it is the same thing over and over and you're basically doing crowd control. In a class, you have more of an opportunity to teach."

Maurin is typical of what non-profit organizations call "episodic volunteers." These are a new breed of community-minded individuals who embrace numerous causes rather than devote a lifetime of service to a single entity.

For much of the past three years, Maurin spent four hours a week as a docent at the aquarium, five hours a week running a film program and leading discussion groups at the East-West Center and two hours a week on the university's Board of Publications. He scaled back in December to focus on his dissertation and kept only his aquarium duties.

"At one point when I was doing all three, it became too much and it was derailing me from my main focus — school," said Maurin, a 32-year-old Manoa resident.

Mary Matayoshi, executive director of the Volunteer Resource Center of Hawaii, said the practice began about five years ago and has become "the biggest trend taking place in volunteer service."

"A lot of people don't have the time anymore," she said. "The old way of volunteering was to volunteer for practically a lifetime with one agency. Now people want to do episodic volunteering, a short-term thing. You work for maybe a week or a day or on a project and it is done."

The trend represents volunteers who place a high value on a social experience with their neighbors, co-workers, friends and relatives, Matayoshi related. They are also driven by a feeling of completion.

Both concepts challenge organizations to come up with manageable, short-term projects with a feel-good quotient. Organizing events well is critical, but the payback is obvious. Consider the Hawai'i Nature Center, which received 6,688 volunteer hours in 2006. The value of that work was more than $125,000.

"It is a creative process," Matayoshi said. "Organizations have to think in terms of new ways of scheduling the work so that it is possible."

The current volunteer is focused and often boasts professional skills best-suited for a specific task, Matayoshi said. Retirees are big contributors and are looking for a range of short-term activities. And families have stepped forward because it gives them quality time.

"A lot of families now prefer to focus on something that is brief and they can do together, and there is a feeling of completion," Matayoshi said.

Volunteers enjoy the diverse range of experiences they can find among organizations eager for their service, even if it's only for a couple of hours a week.

Chelsea Spencer, a 20-year-old marine biology student at Hawai'i Pacific University, gets that and more. She discovered hands-on experience explaining reef creatures to Waikiki Aquarium visitors for two hours a week and while feeding fish, cleaning reef tanks and washing turtles for four to six hours a week at Sea Life Park.

"It's surprising how much you learn from being a volunteer," she said. "I was noticing in a class that I am taking that I am the only one that can name fish species and can identify the fish we see while out in the field."

The practice is perfect for groups whose members regularly come and go, such as high school classes looking for service projects and military units looking to help their new neighbors.

Terri Kojima, a public-affairs officer for Navy Region Hawai'i who spent three years as an environmental outreach coordinator, frequently matches sailors and their families with projects. Last month, she sent 20 people to clean Kapakahi Stream and 100 people to help maintain the Pearl Harbor Historic Bike Trail.

Whether the gig is a one-time activity or something that brings them back, the motivation remains the same, Kojima said.

"For our sailors here, the common statement I hear them say is we want to give back to the community," she said. "We are part of this community and we take pride in it, and this is our way of showing it."

Carolyn Hilton was an accountant for 20 years before she and her husband, Dave, moved from Chicago to Hawai'i Kai to escape the cold. Their solution to being strangers in the tropics was to roll up their sleeves and help.

"Volunteering keeps you young," she said.

Her husband teaches chess to inmates at the Halawa Community Correctional Center, and she volunteers at the aquarium and the Honolulu Academy of Arts, and previously volunteered at Hanauma Bay. Plus, she spent two tax seasons preparing returns as part of a free AARP program, "just for the variety," said Carolyn Hilton, 65, who also attends the University of Hawai'i.

"Variety is the spice of life. And it is more interesting to see and meet interesting people at these locations. It is never the same."

Reach Mike Gordon at mgordon@honoluluadvertiser.com.