The news comes just a couple of months after the death of his colleague and pair of horses Joe Ruby, with whom Spears created the cartoon dog Scooby-Doo.
Spears and Ruby met at the animation company Hanna-Barbera in the late 1950s and began creating cartoon children's programs together.
In addition to "Scooby-Doo", they also made series such as "Dynomutt" and "Hajen Jabbe".
They later started their own company and produced comics such as "Alvin and the Gang" and "Superman".