Duck plays dead to get away from dog

Da fuq? What kind of dog doesn’t pick the bird up?

A guinea came through the yard last week and my beagle got after it. After 30 seconds or so ( before I could get over there) the guinea laid motionless on the ground and the beagle finally left it alone. I thought the bird was dead until I nudged the bird with my foot, then it got up and took off. It was also playing dead.