His focus on ichthyology probably began in the summer of 1874, when he worked as a volunteer at the Fish Commission laboratory in Noank, Connecticut. There, he first met Spencer F. Baird and a number of the young scientists who had gathered around him. First among these was George Brown Goode, who with Bean would form one of the most famous collaborative teams in ichthyology. Bean spent the next two decades in Washington working for Baird's two institutions, the National Museum and the Fish Commission, in a number of capacities. He left Washington in 1895 to become the Director of the New York Aquarium, but political problems led to his resignation in 1898. He spent most of the next eight years working on the fisheries and forestry exhibits at the world's fairs in Paris (1900) and St. Louis (1904). In 1906, he became New York’s state fish culturist, a position he held until his death in 1916 following an automobile accident.