How Climate Influences Wolf Recovery in California
More than 90 years after the last wolf in California was killed, a pack was recently observed near Mount Shasta. Its presence was established by photographs taken earlier this month by trail cameras managed by the California Department of Fish and Wildlife. The department has designated the five pups and two adults seen in the photos as the Shasta Pack, using the name of the large glacier-covered peak nearby. The discovery of the pack is a major step forward for wildlife conservation. The animals, once common in the state, were eliminated by 1924 through a government-funded program.
The precise location of the pack is being kept secret to protect the animals from ranchers who fear that they will prey on their livestock, and from wildlife enthusiasts who might harass them in the effort to take photographs. However, some information about its general location is available. The Fish and Wildlife press releases place the animals within 15 miles of the summit of Mt. Shasta. Since wolf pack territories in the western U.S. average 200-500 square miles, they are likely to travel to the mountain’s extensive slopes.
Are the glaciers on Mt. Shasta one of the reasons that the adults, ranging south from Oregon, chose this location? Without sightings and tracks, and perhaps radio collar recordings, the animals’ precise movements will not be known. But two lines of evidence suggest an association of the Shasta Pack and Mt. Shasta’s glaciers, the most extensive in the state.
Recent conditions might make a glacier peak attractive. In the spring and summer of 2015, Oregon has been in drought conditions characterized as severe or extreme. Drought is commonly associated with reduced populations of key prey species for wolves. Mule deer and elk populations in Oregon are currently low. In this context, predators might be attracted to the relatively green vegetation on Mt. Shasta, supported by the abundant snowmelt in spring and early summer, and glacier meltwater in late summer. A U.S. Forest Service ranger at the station closest to Mt. Shasta confirmed that local wildlife densities were “more favorable than other parts” of the national forest.
Historical patterns in other western states also show that the arrival of wolves has been associated with glaciers. Wolf packs were eliminated in Montana by the 1930s. The first new pack in the state was established in 1979 near Glacier National Park. In Oregon, the first wolf pack in recent times was seen in 2006 in a range with glaciers—the Wallowa Mountains. Similarly, the first pack in recent years in Washington State was recorded—also with a trail camera—in 2008 at Lookout Peak, in the glacier-rich North Cascades. Patterns are less clear in Idaho and Wyoming, where wolf recovery is associated not with spontaneous movements of wild individuals, but with the contentious federal reintroduction programs in Yellowstone National Park. But ), the fact that wolves who entered four different western states all chose sites near glaciers suggests that these high moist areas with few human residents were attractive to them.
Future research may provide additional details of this association of glaciers and wolf introductions in the case of California. In the meantime, we may hope that the Shasta Pack remains healthy and unharmed, and that their offspring will spread to other areas of the state.