Alaska Bison Find Home on the Range
Bison are not subtle. A Copper River gravel bar I recently visited was decorated with manure piles the size of pies, rutted pathways, 10-foot craters in the sand, and soft hair hanging from spruce branches. I was in the lair of the bison, a creature introduced into Alaska in the late 1920s.
Five-to-ten thousand years ago, bison were a common sight in Alaska, flourishing in a climate a bit cooler and dryer than today. Alaska bison finally disappeared in the days of Columbus. Scientists think they died off because of hunting by aboriginal hunters combined with a warmer climate that reduced grasses and sedges.
Bison were reintroduced to Alaska in 1928. Responding to requests from hunters who wanted more species of big game, biologists brought in 23 plains bison from the National Bison Refuge in Moise, Montana. All of the bison were released in the Delta Junction area. By the 1990s, the Delta herd had expanded to more than 400 bison.
Delta Junction, once called Buffalo Center, is one of four regions in Alaska with bison; the other three are populated with bison relocated from Delta. In 1950, Fish and Game technicians captured 17 bison from the Delta herd and moved the animals to Slana, in the upper Copper River valley. The 17 animals multiplied to more than 100 in the 1960s and 1970s, but the herd is a bit smaller now. In 1962, 35 bison from the Delta herd were transplanted to the Chitina River drainage. This herd, which hasn't mingled with the Slana bison, has increased to about 50 animals.
The latest bison transplant happened at the Farewell Lake area, near the western end of the Alaska Range along the south fork of the Koyukuk River. In 1965 and 1968, 18 and 20 bison, respectively, were released. Since then, the Farewell herd has increased to about 300.
According to the Alaska Department of Fish and Game, bison are the largest native land mammals in North America. A mature bull can stand six feet at the shoulder, its body 10 feet long. Bulky but nimble, bison are surprisingly fast, and a bull was once seen hurdling a seven-foot log fence.
These immense creatures eat grasses and forbs such as vetch, a plant in the pea family that often grows on gravel bars. Bison have also been known to eat sedges, willows and dwarf birch, though as ungulates in the same family as cattle they prefer grasses.
The bison currently in Alaska are Bison bison bison, commonly known as plains bison and the same subspecies that roamed the American West a century ago. Native herds of a different subspecies, Bison bison athabascae or wood bison, still live in areas of northern Canada, such as the Mackenzie Bison Sanctuary and Slave River Lowlands of the Northwest Territories.
Fish and Game has proposed transplanting wood bison from Canada to the Yukon Flats, but the agency has met with some resistance from groups that think bison might affect the waterfowl populations in Yukon Flats, one of the major nesting areas in North America.
My thanks to Maria Berger for help with this column. Berger, who now works with the University of Alaska's Reindeer Research Project, wrote her master's thesis on the Delta bison herd.
