Born in Limerick, Ireland, the daughter of a meteorologist, Marian spent her early childhood on Wake Island and in Alaska where she acquired her father's love of science, her mother's artistic bent, and her parent's mutual love of the outdoors. "I assumed that art was a natural part of life, a way that everyone expressed themselves," she says.
During her teens, Marian focused on abstracts until she took a class at Humboldt State University in representational drawing which "opened my eyes," as she puts it. After graduating from Humboldt with a degree in wildlife management, Marian moved to the Big Island in 1976. While studying Hawai'i's wild rats, and working as a veterinary assistant, she continued to paint.
Marian had her first one-woman show at Volcano Art Center Gallery and has had several since. In 1987, she created a series of paintings of Hawai'i's endangered birds and plants for the Aston Kaua'i Resort. An edition of 2000 prints was published, and proceeds from the sales were given to the Hawai'i Nature Conservancy. In 1988 she painted a number of watercolors presented to U.S. Senators Danial Inouye and David Akaka for their contributions in preserving Hawai'i's native wildlife. She continues to receive commissions and to paint independently with consummate skill.