The Owlmen were the disguises of two members of Grey Fox's smuggling ring.
The Scooby-Doo Show
They terrorized a local forest while the gang looked for Velma's Uncle Dave, who they had kidnapped after he discovered the operation. They were also scaring people away from their smuggling operation with a giant owl-like monster called the Willawaw, which was operated by their boss, Grey Fox. They were then captured by Red Herron, along with Grey Fox, to be taken to the council of elders for punishment.