They sometimes search for livestock behind the television when sheep appear on screen, says Geri Byrne, owner of the Border Collie Training Center, in Tulelake, Calif. Left unoccupied, they'll dig up the garden, chew up the doggie bed or persecute the cat.
They are not content to be lap dogs and require homes that can indulge their herding instinct. This breed needs to exercise their athleticism, intelligence, and strong work ethic. If owners cannot run the dogs frequently they can rent a flock of sheep to keep them occupied and to short circuit the boredom that can lead to destructive behavior. Fido's Farm in Washington allows the dogs to practice on the farm's 200-head flock of sheep for a $15.00 fee per dog.
Link - Via Metafilter