Newburyport sculptor Jeffrey Briggs has been asked to design some bizarre carousels in the past, but few compare to his most recent commission.

The carousel company Fabricon Creations brought him in to design a carousel for the city of Detroit to serve as one piece of a public art display anchoring the city's new RiverWalk. The catch? The city wanted the carousel creatures to represent the flora and fauna of the Detroit River habitat.

That meant that instead of horses, Briggs would have to figure out how to put saddles on a wood duck, a bald eagle, a frog, a catfish and a snail, and also make them attractive enough that children would run to claim their favorite when they got on the ride.

"This was difficult in that when you think of a carousel, you think of fantasy," Briggs said, "you think of out-of-reality kind of stuff, but the request was to make things recognizable; a walleye, but with personality."

The city wanted two magical creatures, as well: a river monster and a "multiethnic" mermaid.

Briggs and his wife, sculptor Lindley Briggs, spent months just doing research on the Detroit River wildlife, making sketches and running ideas by city representatives and the carousel company that commissioned them.

Ultimately, they settled on 13 creatures, some of which would appear on the carousel more than once, and a mute swan chariot. Briggs sculpted each piece out of a metal frame covered with plaster. His sculptures were made into molds, which were then used to produce each animal in fiberglass.

"Traditionally, they used to carve them out of wood," Lindley Briggs said, "but plaster is more time-efficient, and you can get the same detail."

Each creature was then shipped to an old-warehouse-turned-artist's-studio on Hale Street in Haverhill, where Newburyport artist William Rogers painted them according to Briggs' design.

One of Rogers' favorite creatures, the snail, was painted to resemble an actual snail shell that Briggs handed him to use as a model.

"He said, 'Do something like this,'" Rogers recalled. "They are supposed to look like actual things."

The eyeballs in each creature were custom hand-blown by a taxidermist to look as real as possible.

"That's the challenge," Lindley Briggs said, "to make things that are fun, but not cute."

Sitting on a plastic chair in a warehouse studio surrounded by the river creatures, Briggs looked over the pieces. His favorite at the moment, he said, is also his most recent creation: the swan chariot. Unlike the others, this piece was not made into a mold and then replicated in fiberglass. It's a one-of-a-kind sculpture.

"I like my swans today," he said.

Later, as he walked among the creatures, he caressed the white, unpainted swan heads. He sat down in his handmade chariot and called to his wife, "Come see if you fit." She slid in beside him and he put is arm around her.

Rogers smiled. "Look at the kids," he said. "Look at them."

Briggs has been working on custom carousels for about 20 years.

He once designed a carousel to go inside a hollowed-out mountain in Finland that was created after Russia invaded in 1939. The cave was supposed to be large enough to protect the entire population of Finland, Briggs said, but about 10 years ago, the nation decided to turn part of it into an amusement park. The carousel featured Finnish designs and local fauna, such as the Lapland deer.

Briggs also worked on a children's carousel to go to Dubai. The challenge, he said, was that the carousel was for an Islamic nation and it couldn't have any human faces or graven images. He could, however, use classic carousel horses and that turned out to be a big hit.

"They, in fact, are entranced by Americana stuff," he said.

The Detroit carousel, which is due to be packed up and shipped by mid-April, is about 90 percent complete, Briggs said.

Rogers still has to paint the 360-degree mural, designed by Briggs, that will be the twirling fulcrum of the carousel. He also will be painting scenes on the carousel's panels and a few more of the ride-on creatures.

Before the carousel leaves the Merrimack Valley, the artists are opening the studio to the public for two days this weekend.

It's something Briggs has never done locally with previous carousels, he said. The animals and magical creatures will be set up around the studio in front of backdrop panels so children can sit on them and have their photos taken.

Rogers said he has already had a seat on the snail's back, just to try it out. Both he and Briggs plan to climb on the finished carousel when it is unveiled in Detroit in May.

"We're going to go to the installation," Briggs said. "I guess we'll give it a try."

By the numbers

* The Detroit River carousel will have 13 original creatures sculpted by Newburyport artist Jeffrey Briggs: a sturgeon, bass, catfish, walleye, egret, eagle, wood duck, snail, frog, heron, loon, river monster and mermaid.

* There will be 19 saddled creatures in total because six creatures will appear more than once. Of the 19 creatures, 17 are jumpers (they move up and down) and two are standers.

* The carousel will have one mute swan chariot.

* At the center of the ride will be a 33-foot mural of the Detroit River estuary and wildlife.

* Briggs made more than 300 drawings before settling on the final designs.

* The finished carousel will include 600 large lights and about 200 small ones.

IF YOU GO

* What: Detroit River carousel open studio

* When: Saturday and Sunday, noon to 5 p.m.

* Where: 140 Hale St., Haverhill

* Cost: Free