On a Monday evening, they took off in the canoes, paddling down the Mississippi River a few miles to a 22-acre island.

There, they let the rabbits loose.

Not too loose, though. Caleb Smith, 15, eyed a Flemish Giant rabbit named Fudge as it hopped around in the sand, snacking on leaves. He placed an Angora rabbit on a table, where it turned this way, then that. He put a pair of smaller rabbits in a makeshift pen.

His guests, a mother-daughter pair visiting from Brooklyn, hung out with one rabbit, then the next, snapping photos and asking questions.

“Are they all friends?” said Lana Krakovskiy, crouching to get a closer look.

“We keep them separated, unless they’re [young] siblings,” Smith said. The few roaming outside cages, he noted, are all male.

A rabbit peeked at the Mississippi River. Caleb Smith hopes to keep his rabbit island rustic, “like the Boundary Waters,” he said.

Smith is a teenage rabbit expert and entrepreneur who uses his dozens of furry friends to educate, comfort and earn income. During the summer months, he and his friends train and hang with the rabbits on Peacebunny Island, near river mile 832, a predator-free paradise where the bunnies can act like bunnies.

Why an island? It’s a bit of a tale.

When Smith was 9 years old, he saw 362 rabbits listed on Craigslist. It was just after Easter.

“People wanted a short-term bunny rabbit,” he said. “They didn’t want the 10-year commitment that goes along with a rabbit.”

He adopted Paxton, a “really gentle, calm rabbit,” he said. “Most rabbits won’t sit on your lap.” But Paxton Peacebunny, a rare American Blue rabbit, “loved to interact with people.”

It sparked an idea. Smith donned a suit and made a business pitch to his mom and dad in the living room of their Bloomington home: He would adopt endangered and rescue rabbits, bring them to events and allow families to foster them for short stays.

“We live in a suburb. We don’t have a farm. How would this ever work?” his mother, Stephanie, said. “The moral of this story is, be careful what you promise your kids, or you might have the most awesome adventure ever.”

Smith launched a fostering program, allowing families to take home rabbits for trial stays. Some 300 families have checked out rabbits over two years. Just two have purchased. (“That shows that the fostering works,” he said.)

He also offers the rabbits as comfort animals, bringing them to schools and places of grief, including the sites of five mass shootings. (“God tells you to go somewhere,” he said.)

He uses the animals to teach kids about science with STEMbunnies, an educational nonprofit. (This is “not just a petting zoo,” he said.)

After hearing about a barn fire in northern Minnesota in 2015, he saved four orphaned Angora rabbits. He now breeds those rabbits and sells their fur, obtained via “gentle haircuts” four times a year. That money, plus a pair of young entrepreneurship prizes, helped Smith’s business, Peacebunny Island Inc., buy a houseboat and make the down payment on Peacebunny Island and two smaller islands that together cost less than $100,000.

“He spent four months out there last summer,” testing the idea for safety and sustainability, Stephanie Smith said. “We thought, Wow, what an amazing place. To be that close to the city and not have noise. … It’s a Tom Sawyer, Huck Finn adventure kind of a thing.”

He’s a State Fair star

At 15, Smith doesn’t yet have a driver’s license. But he does have a nonprofit, an LLC and a mortgage. Plus, 32 blue ribbons from last year’s State Fair. He’ll be there this year, too, with 10 rabbits defending their “best of breed” titles.

That competition judges rabbits against “The Standard of Perfection,” a book by the American Rabbit Breeders Association that sets the benchmarks for every rabbit breed, for such qualities as fur and body shape. An ideal Harlequin rabbit, for example, has ears of two different colors and a face split into two colors that alternate with the ears.

“Caleb is showing some breeds that not many people have, especially in Minnesota,” said Paul Bengtson, superintendent of the poultry and rabbit competition. The rabbit category is competitive, he said, as they’re quiet animals that are easy to care for. But Smith is apt to show bigger breeds that are a little harder to handle.

“He has a nice variety of animals that really adds to the fair show.”

Plus, Smith and his family clearly love to interact with fairgoers, Bengtson said, teaching them rabbit basics.

Smith has enlisted friends, some of whom he knows through church and Boy Scouts, to help train the bunnies as comfort animals. He and those “guardians” bring the bunnies to the island, never leaving them there alone. This is no Usagi Jima, the island in Japan that’s been overrun with rabbits.

Nick Knutson, 19, met Smith through Boy Scouts and traveled with other volunteers to Parkland, Fla., after a gunman killed 17 people at a high school. They brought the rabbits to elementary and middle schools, offering up cuddles, an experience that was “sad and exciting all at the same time,” Knutson said.

“We were going to a place of hurt,” he said. “And we had these wonderful bunnies that were able to take the little kids’ minds off of what was going on around them.

“Everything in the world stopped, and they could just focus on the bunnies.”

A bunny and a blanket

Smith, an only child, wants to bring bunnies to more people. For the first time this summer, he’s hosting hang time with the bunnies at the Savage farm where they stay.

But he also hopes to keep his rabbit island rustic, “like the Boundary Waters,” he said. It’s private, for now, with infrequent guests. On Facebook, Smith has posted a few essay and photo caption contests, offering the winners free boat rides to the island.

Krakovskiy won the caption contest and decided that she and her 13-year-old daughter would turn it into a Midwestern adventure, heading up to the North Shore after their day on the river: “I’ve always wanted to see a Great Lake.” She and Caleb’s mother chatted several times by phone. “It was a leap of faith for both sides.”

On a sunny summer day, the Smiths picked up the Krakovskiys at the airport and brought them to a boat landing on the Mississippi, handing them life vests and paddles. After arriving on Peacebunny Island, the New Yorkers learned the rabbits’ names, breeds and personalities. Krakovskiy’s daughter made suggestions about what to name two younger rabbits: “Licorice and Marshmallow.”

Krakovskiy settled into a hammock, and Smith placed a blanket and a bunny on her lap.

“I think he’s falling asleep,” she said after a while, peering at the white and tan rabbit. “He’s closing his eyes.”

Then she leaned back and noted that she was pretty relaxed, too.