Even though the habitat is marginal, a considerable fishery exists for walleyes in the Des Moines River. Tagging studies indicate the annual rate of harvest to be about 10 percent. The size of the population is evidently limited by frequent fish kills due to high water temperatures in the summer and oxygen depletion in the winter. Considerable variation in growth exists within age groups and between year classes. Possible explanations include: (1) sexual differences, especially between fish over four years old; (2) frequent fish kills which result in vacancies in the habitat; (3) low water levels during certain years; and (4) frequent stocking of fry, fingerlings, and yearlings during different seasons. The growth and general well-being of Des Moines river walleyes are about average when compared with those in other parts of the country.
Proceedings of the Iowa Academy of Science
©1959 Iowa Academy of Science, Inc.
Schmulbach, James C.
"Growth of the Walleye in the Des Moines River, Boone County, Iowa,"
Proceedings of the Iowa Academy of Science, 66(1), 523-533.
Available at: https://scholarworks.uni.edu/pias/vol66/iss1/72