Let’s call writing Kristen Britain’s third career choice, but her true calling.

The Bar Harbor resident, whose second fantasy novel, “First Rider’s Call,” was published by DAW Books in August, has been writing since her youth. It’s only in recent years that she’s felt financially secure enough to take the leap and make writing her career.

Britain, who lives in a log cabin with her enthusiastic Irish terrier Gryphon, worked for the National Park Service from shortly after she graduated from Ithaca (N.Y.) College (with a degree in film production) in 1987 until earlier this year, spending the last 10 years at Acadia National Park.

Her work for the park service, as well as communing with nature, helps the backdrop of her new novel and its predecessor, 1998’s “First Rider,” really come alive.

“It gave me lovely settings, a sense of history and place,” said Britain, 37. “It’s very inspiring for the writing process.”

Many of the elements in her current series came from a novel Britain wrote as a teenager.

Her central character is Karigan G’ladheon, who is a Green Rider, one of the king of Sacoridia’s elite magical messengers. Karigan has undergone quite a transformation from when Britain began writing “Green Rider” in 1992.

“Originally, Karigan was a minor character, and male,” Britain recalled. “But the character demanded to be female, and demanded more attention. So I changed the whole thing and wrote about who she was, and why.”

A merchant’s daughter, Karigan gets caught up in danger after being a good Samaritan. She comes across a dying Green Rider on the road and agrees to deliver a “life and death” message to King Zachary of Sacoridia.

Karigan ends up in the middle of a battle with Shawdell, a rogue magician and member of the immortal Eletian race, who has cracked the magical D’Yer Wall. That structure has protected the region for a thousand years from the evils of Blackveil Forest – the prison of Sacoridia’s ancient enemy, Mornhavon the Black. So Shawdell has loosed dark magic upon the land. At the end of “Green Rider,” Karigan helps to defeat Shawdell and save the king’s throne.

In “First Rider’s Call,” Karigan has returned home to Corsa, determined to resume her familial duties. But she can’t resist the Rider’s call, and finds herself smack in the middle of the intrigue going on in Sacoridia. In addition to political infighting, an evil has awakened in Blackveil Forest and the Riders’ magical powers are going haywire.

Britain can understand how such a roster of characters and settings could be challenging to readers.

“I kept a glossary of characters and places, or else I would have been completely lost,” she said.

Britain’s routine involves sitting in her comfortable armchair and writing longhand on a pad of paper, without a set number of pages or hours in mind. After she gets a couple of chapters done, she inputs into her computer, editing as she goes.

When Britain started “First Rider’s Call” two years ago, she didn’t have too much planned out ahead.

“I had basic ideas of what the story arcs were, but I was pretty much starting over,” she said.

While it took her close to a decade to get her first novel published, Britain felt more pressure while writing the second one.

“I knew too much, and too little, about the process,” she said. “There’s knowing there’s an audience out there, and expectations from the publisher. Also it’s harder to juggle all those plot lines, rather than starting fresh.”

Late this summer, Britain was invited to her first World Science Fiction Convention, held in Toronto.

“It was a blast,” she said. “I participated in panels, did a reading, and saw some old friends. I got feedback from people happy with the book, but heard nothing critical.”

Britain is contracted for two more books in the “Green Rider” series. This means she needed to balance tying up the bulk of the plot lines in “First Rider’s Call” while leaving room to continue the story in future books.

“I’ve got a vague idea of the story arc, but I can’t outline the whole series,” she said. “I can’t bring too much closure. I have to manage my story line.”

When will the next book in the series be out? Basically, when Britain finishes it.

“DAW would like to see it in a year’s time,” she said. “But I realize I have to go at my own pace, and not let that get to me.”

For upcoming appearances by Kristen Britain, check www.kristenbritain.com.