FREEPORT — Frank Donald Dorsey, 86, died peacefully at his home, with family by his side, on Sept. 18.

A longtime resident of Freeport, Dorsey was born in Portland, the son of F. Donald Dorsey and Elsie Brown Dorsey. He graduated from Deering High School, Class of 1946.

Dorsey went on to attend Bowdoin College, where he earned a degree in biology in 1950. He continued his education by earning two master’s degrees, in biology and molecular biology, at Simmons College and Syracuse University.

He served in the Korean War as a private in the U.S. Army. He then taught biology at Falmouth High School for 11 years, and maintained connections with his students for many years later.

In 1967, he began teaching biology at the University of Southern Maine, with a special interest in marine biology/oceanography, until his retirement. While at USM, he took a sabbatical to study at the University of North Wales. He also spent 19 summers participating in summer training cruises with the Maine Maritime Academy, conducting oceanic plankton studies, and traveling to many places including the Galapagos Islands and Russia.

He enjoyed boating, traveling, dining out (preferably with dessert), opera, old movies, and family and friends. His positive attitude and zest for life were contagious, and he was known for his sense of humor and generosity. He particularly enjoyed watching his pets, Spike and Jetta, play together.

Dorsey is survived by his wife, Lorna, and their six children and 12 grandchildren: Mark and Torrie Dorsey, and children Kate and Thomas; Maria and Jim Logan, and children Toby, Caulin and Clara; Eliza Dorsey and son Jake; Laura Dorsey and Hargrave Garrison, and child Myah; Paula and Kenneth Vosmus, and children Sarah and Ted; and Michael and Kristen Dorsey, and children Kyle, Mikaela and Elias. He is also survived by his sister, Anne Loth.

There will be no services. In lieu of flowers, the family asks that memorial donations be send to one’s favorite charity.