Within the 2.5 million acres of the Yukon-Charley Rivers National Preserve in central Alaska, wolves and other majestic animals are protected. But animals like wolves do not respect lines drawn on a map. And a recent study suggests that efforts to limit populations of these predators outside those borders is having negative effects on wolves living within the preserve.

The study, published in June in Wildlife Monographs, suggests that when the Alaskan authorities were limiting wolf populations outside the Yukon-Charley preserve, survival rates of wolves within the preserve were lower than usual. The findings highlight the notion that managing wildlife within human-imposed boundaries requires communication and cooperation with the authorities beyond a preserve’s boundaries, and could have implications for wildlife management programs elsewhere.

Since the 1990s, the Alaska Department of Fish and Game has spent millions of dollars, first sterilizing wolves, then shifting to shooting and killing hundreds of the animals from helicopters (independently, it announced the planned suspension of the program next year). The wolves were targeted as part of an intensive predator management program in the Upper Yukon-Tanana region aimed to increase the population of the Fortymile caribou herd in lands surrounding the preserve. Once estimated to number in the hundreds of thousands, the caribou herd fell to just 6,000 in the 1970s and now generally peaks at about 50,000 to 60,000. And evidence has built up suggesting that these efforts may be ineffective at increasing caribou in this area.

After 22 years monitoring wolves in the preserve using radio collars, the researchers, led by John Burch, a wildlife biologist for the National Park Service, were not surprised to find that wolf survival rates decreased during lethal management outside the preserve in the Upper Yukon-Tanana Predation Control Area. “Every single wolf pack went outside the bounds of the preserve,” Dr. Burch said. The state never shot wolves inside it, but many wolves that left the boundaries of Yukon-Charley were shot and killed.