VOICES Voices Icon Ideas and Insight From Explorers


Bringing Back Bison–Brings Back Biodiversity

Bringing back the wood bison is not just about the restoration of a charismatic mega-vertebrate.  Indeed, the wood bison–the larger of the two subspecies of the American bison–is a magnificent beast and reintroducing the subspecies is a heck of an achievement. But its return to Wild Alaska signifies much more.

I’m privileged to be able to watch a herd of over a hundred head of this endangered subspecies just outside my office window everyday as they romp around and plow through the snow in their paddock, perhaps eager that Spring is just around the corner. But they very much thrive in the cold and are well suited for it, just as they are really adapted for all kinds of climates.

Wood bison outside my office window at the Alaska Wildlife Conservation Center

Bulls and subadult males are separated from the cows and calves this time of year. They play and mock fight–testing each others’ strength and then spend much of the day grazing on supplemental feed (i.e., hay) or chewing their cud and resting to conserve heat during colder periods of the year.

This is the largest, and perhaps most sustainable captive herd of wood bison in the world and soon many of them will be prepared for a soft release at designated sites in the Interior of Alaska.

But the collaborative conservation effort between the Alaska Wildlife Conservation Center and the Alaska Department of Fish and Game is not just about returning one species, although clearly a flagship species, to the wild here in Alaska. The restoration of this giant, grazing herbivore will change the landscape of Alaska’s interior region, returning it to an ecosystem continually modified by these large bovids.

We know from recent research that bison are a keystone species for conservation and habitat restoration. These large bovids have proven to increase biodiversity on the landscape by altering the temporal and spatial characteristics of vegetative growth. They also promote the restoration of subterranean carbohydrate reserves, alter soil composition, inhibit woody plant growth, catalyze nitrogen cycles, and influence the impact of wild fires on the environment.

Furthermore, because bison are both selective grazers within a grassland ecosystem and with respect to the species they consume while foraging, and as I alluded to, they alter the floristic characteristics of the landscape, providing opportunities for different plant species to coexist in the same general locale. In the prairie, for example plains bison prefer the most dominant plant group (i.e., grasses) to feed on, giving disadvantaged species like forbs an opportunity to flourish.

Wood bison (Photo By Jordan Schaul)

Not only do they continually modify their environment horning, rubbing, and trampling things day after day, they leave behind opportunities for new life creating microhabitats and some cases altering the immediate large scale environment or macrohabitat.  As they paw at the ground they create large divits, exposing the soil. They then roll around creating a depression in the ground.

These wallows may be used over and over again by several individual bison. Wallows often reach more than 15 ft in diameter and a foot in depth.  The packed soil reduces the infiltration of rain water and encourages water retention such that large pools evolve into aquatic ecosystems complete with invertebrate fauna, small ectothermic vertebrates and freshwater vegetation.  In addition, the wallows become watering holes for an array of larger bird and mammal species.

As a consequential benefit, restoring wood bison will not only provide additional prey for predators and potentially subsistence hunters, but as mentioned, it will balance an ecosystem which has been inappropriately manipulated by people for hundreds of years.

Everyone involved with this project is very anxious to see these animals returned to the wild.  Mike Miller, the Executive Director of the Alaska Wildlife Conservation Center acknowledges this great conservation achievement stating that “this is was one of America’s most monumental conservation efforts in the the country’s history.” He often says that “it is an opportunity to undo a wrong.”

If you’d like to learn more about the project, please visit this link.


  1. Lisa
    March 4, 2012, 12:15 am

    How many are going to be roadkill?