Marvin Grosslein

Long-time Falmouth resident Marvin D. Grosslein passed away January 19, 2026 at age 96. He married Avis Bye in 1953. They were devoted to each other for more than 72 years.

Marvin was born in Seattle, WA in 1929 to Martin and Agnes Grosslein and grew up in Minnesota. He attended the University of Minnesota for his undergraduate and Master's degrees, spent two years in the U.S. Army, and earned a PhD in fisheries biology from Cornell University in 1961.

He began work at the National Marine Fisheries Service in Woods Hole in 1961. He developed a novel sampling approach to estimate North Atlantic fish population sizes and age distributions. The data were used to study ocean ecology and to try and prevent overfishing. He served as Senior Scientist and Officer in Charge of the lab before retiring in 1994.

He was an accomplished violinist and loved playing chamber and orchestral music. He encouraged his kids to practice hard and to their chagrin they eventually realized that he was right. In retirement, he played violin with several groups, most recently the Falmouth Chamber Players. He was an active member of the Unitarian Universalist Fellowship of Falmouth, The 300 Committee, and the Falmouth Town Democratic Committee.

Marvin was humble, generous, and well-respected by colleagues and friends. He was a loving father and beloved by his family. Marvin and Avis raised 4 sons: Ron and wife Louise, Jim, Jack and wife Lyn, and Mark. He was predeceased by Jack. He had 7 grandchildren: Martin and wife Sarah, Anna and husband Erich, Abby, Kate, Sara, Chris and Zac, and 5 great-grandchildren: Corinne, Kirk, Kayleigh, Katherine and Clark. He is also survived by his brother Roger and wife Judy and their family.

Marvin instilled a love of the outdoors in his kids and had a great sense of humor. It was fun to see him consumed with laughter, while watching Pink Panther or Laurel and Hardy movies. With such a responsive audience, his kids got really good at telling funny stories. He and his wife Avis showed how rewarding life can be with some luck, a lot of hard work, and a lot of laughter.

A Memorial Service will be held at the Unitarian Universalist Fellowship of Falmouth (UUFF), April 4, 2026, 10AM.

In lieu of flowers, memorial gifts may be made to the UUFF, 840 Sandwich Road, East Falmouth 02536 or The 300 Committee Land Trust, 13 Thomas B. Landers Rd., East Falmouth 02536.