The Merced County Sheriff's Department said the 53-year-old man was hunting with a partner off Highway 152 near Los Banos when he set down his shotgun to retrieve his decoy ducks.
The shotgun was loaded but the safety was on, according to authorities.
The victim was about 15 yards away, retrieving his decoys, when his female black Labrador retriever stepped on the gun.
Authorities said the dog disengaged the safety and hit the trigger at the same time, firing a shell with #2 shot. The man was struck in on the left side of his upper back.
The man was treated and released at the hospital the same day.
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