As a puppy, Flicker got curious and followed an ant trail into the woods when no one was looking; hours later, he returned thirsty, hungry, and covered in little itchy ant bites. As his mother cleaned his wounds, the she's simply grateful he's returned relatively unharmed and hopefully learned a lesson or two...
As an adult, Flicker will step on any ants unfortunate enough to come close to him. He feels a petty, vindictive glee doing this, as he still remembers the days of itchy agony and his littermates' teasing at his misfortune.