Rodney Johnson isn’t your average 71-year old. He has white hair, laugh lines, and sandcastle supplies. Lots and lots of sandcastle supplies.

Johnson is better known around Onset Beach – his self-described “home base” – as “The Sandman,” and even has shirts and a sign proclaiming himself as such. Whenever a passerby stops to admire his sand sculpture work, and asks how Johnson learned his craft, he always begins the story the same way: with a miniature dragon.

“I watched a gentleman down in Revere Beach … teaching a five-year-old kid how to make a dragon,” Johnson said. “I looked over, and I said, ‘I never made nothing like that in my life, and she’s five years old!’ … I decided to make a small one … and, if it didn’t come out, I could step on it, and nobody would know.”

But it did come out, and the rest, as they say, is history. Now, 15 years later, Johnson has expanded his repertoire to include 39 different creatures he can sculpt from sand. Johnson, who is part Sioux and Blackfoot, finds inspiration in some of the Native Americans’ traditional animals of power, such as the eagle.

“I make eagles, and I make nests with baby eagles coming out of the eggs,” Johnson said. “Eagles are strong things for Native Americans.”

He also puts his own personal spin on the creations, by spray-painting them.

“[The paint] is so light, the wind just picks it up and takes it away, after a few hours” Johnson said.

Johnson’s wife, Carol Johnson, said her husband has held several different jobs over the years. Among his various professions, he has been everything from a protection officer at the Federal Reserve in Boston, to a security officer at Harvard University. After hurting his back as a parking attendant at MassGeneral Hospital, Johnson decided it was finally time to retire – but Carol Johnson said the spry septuagenarian is so dedicated creating sand sculptures, it might as well be work.

“He thinks it’s his job,” said Johnson. “He is always thinking of different things to create, and his mind is always calculating.”

Johnson’s favorite creation is a killer whale he made several years ago. He said it took him almost four hours of shoveling sand to create, and was pleasantly surprised to find it wasn’t just the beachgoers who enjoyed the day’s work.

“The Harbormaster called me into his office – I thought I was going to get in trouble!” Johnson said. “He turned the computer around, and said, ‘All your work is going all over the world – Israel, Germany, Russia, Mexico.’”

But for Johnson, his work is more than just art he and others can enjoy. It is a way of teaching the curious youngsters who flock to his sand creatures to protect the environment.

“[The kids] have all these [live] animals they want to show me, and I will say, ‘That’s very nice, now put it back,’” Johnson said. “I try to treat it as a teaching job, not to destroy things, but to protect them. No one else is doing it – when they go get live crabs or fish out of the water, the families are not saying, ‘Put it back.’”