The spunky terrier named Jack was found yapping and snapping at the big cat that snarled back at him from his perch in a tree on Virtus and Chad Strenge's farm in Colman earlier this week.
""He trees cats all the time," Chad Strenge told The (Sioux Falls, S.D.) Argus-Leader. "I suppose he figured it was just a cat."
Strenge said he blasted the lion out off the tree with a shotgun but it took off with Jack in hot pursuit.
The lion was eventually dispatched with another shotgun blast.
A South Dakota State University professor, Jonathan Jakes, told the Argus-Leader that the animal may have moved on to the farm after being pushed out of its own territory by another lion. As for Jack's heroics, Jakes said the lion probably wasn't too intimidated.
"It probably wasn't hungry, and that could be why he didn't just scarf it (the dog) down, but we can't say for sure," he said.