Hugh, son of Thomas and Cornelia Smith, was born in Washington, D.C., on November 21, 1865. Hugh attended high school in Washington, and went on to earn his degree from Georgetown University in 1888. He was intrigued by ichthyology, which motivated him to continue his post graduate medical study in New York (LLD). He worked for the U.S. Fish Commission as an assistant in 1886, and from 1897 to 1903, he was the assistant in charge of scientific inquiry. He also became the director of the biological lab for the U.S. Fish Commission in Woods Hole, Massachusetts. Hugh was co-special agent in charge of the fisheries 10th Census. He was also the deputy commissioner of fisheries in 1903, and worked as the editor of the Bureau of Fisheries in 1904. He was a member of the medical faculty at Georgetown University from 1888 to 1902, and was a professor of normal histology from 1895 to 1902.

Hugh’s love of fish drew him to other countries to study the many aspects of the area’s fisheries. At various international fishing congresses he was a representative for the United States. He published numerous reports and papers on ichthyology, economic fisheries, and pisciculture as well as contributing to technological and popular periodicals. He was a fellow of the American Association for the Advancement of Science.

He was awarded an honorary membership in the Washington Biologists’ Field Club in 1921.

He lived in Washington, D.C., until his death in 1941.