Christopher Smith was house-sitting for his mother in her mobile home when an entire bag of dog food disappeared from the laundry room last week.
He thought racoons had eaten it.
But the next night, a big bear got into the home.
Smith says he instinctively rushed to protect his two children and pets.
Then the bear swiped at his foot, injuring him.
"The fear hit first and then the adrenaline hit and as soon as the adrenaline hit, all the thoughts came in of what I need to do and how short of a time I might have for this bear to get over the washer and dryer, get through the door an get into the house," recalled Smith.
Smith says the bear seemed to have a routine and came around the mobile home for at least four nights around midnight.
The California Department of Fish and Wildlife is investigating the encounter, including DNA from Smith's injuries.
Officials say the results will determine if the bear will be relocated.