Okay, I might not have been that clear.
The hunters want to separate the herds. They will scatter said herds, but not until they're ready.
How I pictured it was setting off explosives and some explosive tripwire at strategic locations (all game canon am I awesome or what?) to scare the Grazers in one direction and the deer in another. The deer would be driven into the hunter's local to be shot down, while the Grazers fled away from the hunters, thus taking the Thunderjaw with them. Thus leaving the hunters in peace.
But if the trap goes off too soon, animals and machines will go every which way and leave the hunters vulnerable to the Thunderjaw.
Did that clear it up?