The Gorilla Wrestler and His Dog

In Africa a camera crew has been assigned to get footage of the World Famous Gorilla Wrestler at work. The camera crew is in the truck with him and his dog, and they come across a small tree. The wrestler says to them, "Just wait here, I'll be right back."
He climbs the tree, wrestles with a gorilla for a while, then throws it to the ground. Quick as a flash, the man's dog jumps on the poor animal and has sex with it until it faints. The man throws it in the back of the van, and they drive on to a medium-sized tree with a medium-sized gorilla. And the same thing happens.
Then they're driving along, and there's a huge tree with an absolutely massive gorilla in it. THe man hands the cameraman a gun.
"What's this for?" the cameraman asks.
"Well, there's a small chance that I might lose the battle here. And if I do, shoot the dog!"