Put on a Gilly suit, put your nose in the wind and go down in the canyons after them. Use your ears, and then when you sneak up on them unload and shoot as many as you can. Wait ten or 15 minutes and go after them again. They scatter like quail when you bust them, then they will start grunting and come back together.
I used to live down on the Wa****a and have hunted them a bunch.