Big Mona is a giant catfish sought after by Snakebite Scruggs.
Big Mona is a huge catfish.
Big Mona seems to hate dogs.
Scooby-Doo On Zombie Island
When Scooby-Doo was on Jacques's boat, he saw a giant catfish, Jacques said that the catfish must be Big Mona. Big Mona didn't like dogs so it splashed water on him. Scooby was so mad that he decided to teach Mona a lesson. However, Shaggy Rogers and Scooby fell overboard, drawing the attention of two alligators.
Snakebite appeared in his boat and shoved his hook spear and into one alligator and the other one bit the hook to it.
The alligators left, and Snakebite introduced his hunting pig named Mojo. Big Mona appeared again and squirted water at Scooby.
By the end of the gang's stay, Snakebite and Mojo finally caught Big Mona, but Scooby flew off of the boat, and into the air knocking Big Mona out of the net and swam back into the river.