Hamerstroms focused on the habitat needs of the greater prairie chicken. They developed and initiated a management plan based on their observation that the prairie chicken required a "checkerboard" pattern of habitat. Frances worked for the Department of Natural Resources for 23 years, and in 1970 the Hamerstroms were awarded with the National Wildlife Federation Award for Distinguished Service to Conservation for their innovative management plan and work with the prairie chickens. The Hamerstroms helped focus public attention on the need for habitat preservation. In 1961 they helped form the "Society of Tympanuchus Cupido Pinnatus" (Latin term for prairie grouse) to purchase lands (a total of more than 2,000 acres) to be managed for the preservation and restoration of "native prairie grouse populations." Through her fund-raising campaigns, grasslands near their home sheltered more than 2,000 greater prairie chickens. The Hamerstroms are credited by naturalists for saving the prairie chicken from extirpation in Wisconsin. Over the years, an estimated 7,000 wildlife observers (called "boomers") participated in the collection of necessary data for this project, with Frances playing host to all of them at her home. The Hamerstroms also conducted a decades-long study of the northern harrier. She wrote Harrier: Hawk of the Marshes, published in 1986 by the Smithsonian Institution Press, with illustrations by her husband. It documented the relationship between the breeding success of harriers and the vole population, which constituted their cyclical food supply. Frances noted that the vole abundance determined the harriers' mating system, and documented her findings in a 1985 article "Effect of Voles on Mating Systems in a Central Wisconsin Population of Harriers" which earned the Edwards Prize for best paper of that year. Frances Hamerstrom was also a licensed falconer. She studied American kestrels and the use of nest boxes as a management tool for kestrels, and banded thousands of raptors in Wisconsin and in other parts of North America during her many travels. She contributed to the book, Peregrine Falcon Populations: Their Biology and Decline (1998). Wildlife author As a writer, Frances provided insight into academic science for general readers. She wrote over 100 different technical articles and 12 different books, including several popular children's books. Several notable books include: An Eagle to the Sky (1970) Birds of Prey in Wisconsin (1972) Walk When the Moon is Full (1975) Strictly for the Chickens (1980) Is She Coming Too?: Memoirs of a Lady Hunter (1989)