John Paul Visscher (1895 – February 11, 1950) was an American protozoologist and was a professor and later head of the Biology Department of Western Reserve University in Cleveland, Ohio.
From 1920 to 1922 he was an instructor of zoology at Washington University in St. Louis, where he served as a mentor to Francis Otto Schmitt.
[4] Starting from 1922 to 1925 he worked as a special investigator for the United States Bureau of Fisheries, with whom he spent most of his summers.
In 1928 he published his book, Nature and Extent of Fouling of Ships' Bottoms, which was based on his research.
Ten years later, he became a consultant at the Naval Research Laboratory in Washington, D.C.[3] Working at Western Reserve University in Cleveland for many years, Visscher had an impact on its biology department as well as the northern Ohio community and local organizations relating to biology.