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USNR Commander (Ret.) Mary Sears, Ph.D.

July 18, 1905 – September 2, 1997

“The Conscience of Oceanography”

Mary Sears, Scientist Emeritus, Biology.

Mary Sears, Scientist Emeritus, Biology. (Photo by Tom Kleindinst, © Woods Hole Oceanographic Institution)

Mary Sears was the Oceanographer of the United States Navy—the first in modern times. She played a central role in the founding and formation of the Woods Hole Oceanographic Institution. Over the course of her career, Sears was an architect of the world community of oceanographers and the founding editor of Progress in Oceanography and the co-founding editor of Deep-Sea Research. She also edited the book Oceanography, which was published by the American Association for the Advancement of Science in 1961. The journals and books she edited are what oceanographic research continues to be evaluated against today.

Born in Wayland, Mass., Sears grew up exploring the natural world around her, collecting animals—particularly frogs—and setting up terrariums. This passion would forge her life’s path. She graduated from Radcliffe College in 1927, then receiving both her Master’s degree and Doctorate from Radcliffe in quick succession. Her dissertation adviser, Henry Bigelow, was the founder and first director of the Woods Hole Oceanographic Institute (WHOI) and played an important role in mentoring Sears. In particular, he introduced her to leaders in marine sciences of the day and hired her as one of the first ten research assistants at WHOI–the first and only woman of the ten–where she played a leading role by assisting in its founding and later in its purchase of two oceanographic ships.

By 1939, Sears was a junior biologist and by 1940, once WHOI was a year-round organization, a planktonologist. She served as the staff planktonologist until 1963 when she became a Senior Scientist in the Biology Department until her retirement in 1970. Sears additionally served as a research assistant to Bigelow at Harvard, tutored at Radcliffe, and served as an instructor at Wellesley College throughout the 1930s and 40s. It was her time in Peru, via Wellesley College, that finally allowed her to work onboard research ships with men–something that was considered male-only territory and forbidden to women at the time. She left WHOI briefly for a position that brought her numerous accolades and likely helped change the path of the Second World War in the Pacific Theater.

Mary Sears christened the R/V Atlantis II on September 8, 1962. Built at the Maryland Shipbuilding and Drydock Company in Baltimore, MD, the Atlantis was the first ship in the modern fleet of oceanographic research vessels built to serve the United States academic research community. Its design and planning process served as the model for a generation of research vessels to follow. (Photo courtesy of WHOI Archives © Woods Hole Oceanographic Institution)
Mary Sears at the R/V Atlantis II launching. (Photo courtesy of WHOI Archives © Woods Hole Oceanographic Institution)

A Lifetime of Service

In 1943, Sears joined the Women Accepted for Volunteer Emergency Service (WAVES) as a Lieutenant, Junior Grade. Such military service on the home front and overseas, as well as in support of work for the war effort, opened the doors of opportunity for many women around the world.  Since ships were off-limits to women, Sears headed to Washington, D.C., to serve in the U.S. Navy’s Ocean Unit of the Hydrographic Office, which was understaffed, under supplied, and given menial research tasks at the time.

“We were working so hard for a common cause, I was hardly aware of any barriers.”
—Mary Sears

Within one year, Sears grew the unit into a division that would eventually become the Naval Oceanographic Office of the Navy Hydrographic Office, where she oversaw more than 400 people – more than on many Naval ships. Under Sears, the unit was charged with aiding the Navy in strategic maneuvers by providing analysis of surf heights, tides, and other pertinent information to provide mission planners and commanders with strategic advantages over the enemy. Her intelligence reports, “Submarine Supplements to the Sailing Directions,” predicted the presence of thermoclines – areas of rapid water temperature change – that allowed submarines to hide and escape surface sonar used by the enemy. Her reports provided intelligence for all possible targets for good amphibious landing operations and likely changed the course of the war in the Pacific Theater by helping to diminish the enemy’s prior ability to detect U.S. submarines. In 1946, Sears was awarded the Johannes Schmidt Medal for her contributions to marine science research and Navy oceanography during WWII. The following year, Sears returned full-time to WHOI, while maintaining her position with the U.S. Navy as a reservist. When she retired from the USN Reserves in 1963, she did so with the rank of Commander.

Mary Sears posing for a photo. (Photo courtesy of WHOI Archives © Woods Hole Oceanographic Institution)

A Powerful Force of Nature

In this 1960 photo, Mary Sears is surrounded by papers and biological samples in her Bigelow Laboratory office. (Photo by Redwood Wright, © Woods Hole Oceanographic Institution)

Throughout her life, Sears would receive numerous accolades and awards for her work. Other military awards, in addition to the Schmidt Medal, included the American Campaign Medal, Naval Reserve Medal, Armed Forces Reserves Medal, and the World War II Victory Medal. She was involved in her local community and believed in mentoring and helping those coming up the ranks. Education was incredibly important to Sears and every mailbox in her neighborhood that belonged to the house of a child would be periodically filled with books for each young person in the home—a gift from “Aunt Mary.”

Sears was a member of numerous professional organizations and societies, including the American Association for the Advancement of Science, the American Academy of Arts and Sciences, the Society of Women Geographers, Sigma Xi, the American Association of Limnology and Oceanography, and the American Geophysical Union. She helped establish and chaired the First International Congress on Oceanography at the United Nations in 1959 and served on the Joint Committee on Oceanography of the International Council of Scientific Unions from 1958-1960.

At WHOI, she was a long time member of the Corporation, serving as Clerk of the Corporation from 1947-1973 and Deputy Clerk from 1973-1975, and was named Honorary Trustee and Honorary Member of WHOI in 1976. She retired from WHOI in 1970 and became Scientist Emeritus in 1978. In 1994, Sears was the first recipient of the Women Pioneers in Oceanography Award by WHOI. By 1999, two years after her death, it was renamed to include her name—The Mary Sears Women Pioneers in Oceanography Award. In 2000, the U.S. Navy named a 330-foot oceanographic survey ship after her and it is still in use.

USNS Mary Sears (TAGS-65)

USNS Mary Sears visits WHOI in July 2002. (Photo by Tom Kleindinst, © Woods Hole Oceanographic Institution)

Commissioned in 2000, the USNS Mary Sears is seen here making a port-of-call at the Woods Hole Oceanographic Institute from July 24-26, 2002. The 300-foot ship was the first naval oceanographic ship named for a woman by the US Navy.  Commander (Ret.) Mary Sears, Ph.D. was one of the ten founding scientists at WHOI–and the only woman. She served in the Navy WAVES during World War II creating the Naval Oceanographic Office and developing the intelligence reports for the Navy that allowed naval submarines to escape sonar detection by the enemy. She retired from the Navy Reserves in 1963 with the rank of Commander. Sears worked as a Scientist and Senior Scientist at WHOI from 1932 until her retirement in 1970.  In 1978, WHOI named her Scientist Emeritus.


A 300-foot vessel, the USNS Mary Sears is officially launched on October 19, 2000 in Pascagoula, Mississippi by VT Halter Marine where it was built. It is a Pathfinder-class oceanographic survey ship that carries twenty-four civilian and twenty-seven military crew members and continues to be in service.

USNS Mary Sears Launch in Pascagoula, Mississippi. (Photo by Shelley Dawicki, © Woods Hole Oceanographic Institution)

Jascin N. L. Finger is the Nantucket Maria Mitchell Association's Deputy Director and the Curator of the Mitchell House, Archives, and Special Collections. Maria Mitchell was America's first woman astronomer.

August 2022