I worked at a chicken farm in South Jersey in the early 1970s. Every once in a while the owner would have a old buddy bring his Rat Terriers around to sniff out and chew up rats. We would follow them around and help them flush out the vermin. Great times!
A rat hunt meant dressing in long pants, arming ourselves with baseball bats, golf clubs, spears, and a pellet gun or two, getting the neighborhood dogs together into a pack, and then sweeping through the orange grove late on a Saturday afternoon. This had been done so many times that all it took was agreement among the older boys to hold a rat hunt and the arrangements quickly fell into place.
I realized years later that the entire business was like many paleolithic hunting parties must have been organized. The funny part was how our mixed breed pack of dogs behaved. They worked remarkably well together, intuitively getting what we wanted of them, finding rats in patches of weeds and in orange trees and corralling them for us to kill.
Every now and then, an excited dog would kill a rat and sometimes eat them. That seemed natural behavior for a German Shepard, but it was quite something to see it from an old and pampered Cocker Spaniel. Looking back though, we likely would have done much better with a small pack of rat terriers -- but we would not have had as much fun.