In 1995 and 1996, conservationists' lawsuits to bring back wolves in the Yellowstone Park area (in Idaho, Montana, and Wyoming) succeeded: wolves were reintroduced after having been poisoned and trapped almost out of existence. The species thrived, paring back excessive growth in elk and coyote populations, but also paring back growth in nearby ranchers' herds. Today, ranchers contend that, "People who want it here should share the costs" and are in some cases taking money from conservation groups to pay for measures like electric fences and mounted riders. However, such measures are often inadequate, and other times, ranchers have taken conservationists' money and put it to other uses, such as hiring helicopter-riding wolf hunters.
A complicated problem with no easy solution; at least sharing the costs seems like a good way to start.