Died February 16, 2008 in Raleigh, NC.

Hassler served as a member of the faculty of North Carolina State University from 1953 to 1982. He did research on fish ecology and fisheries in many parts of North Carolina. His best known research involved a 27-year study of striped bass abundance in the Roanoke River and Albemarle Sound. Hassler graduated from the College of Arts and Sciences.