Restoration of wild herds could help restore grassland ecosystems
By Bob Berwyn
SUMMIT COUNTY — An international conservation group is suggesting that bison herds could once again roam the grasslands and forests of North America — but only if there is a significant shift in public attitude about the animals.
“The key is recognition that the bison is a wildlife species and to be conserved as wildlife, it needs land and supportive government policies,” said the University of Calgary’s Dr. Cormack Gates, who co-edited a recent report on North American bison and serves as co-chair of the International Union for the Conservation of Nature’s bison specialist group.
Restoring bison could be one of the most ambitious wildlife conservation projects ever attempted, considering the amount of rangeland they would need to thrive in the wild. Alaska wildlife biologists are considering a plan to restore wood bison, and there is a remnant bison herd in Yellowstone. But in other parts of North America — including Colorado — the animals are managed primarily as livestock.
The Colorado Division of Wildlife currently has no plans to consider bison restoration, said spokesman Randy Hampton.
As recently as 500 years ago, tens of millions of bison roamed the plains from Alaska to northern Mexico. But now the American bison — which includes both plains and wood bison — is listed as near-threatened on a global Red List of at-risk species.
As of 2008, there were approximately 400,000 bison in commercial herds in North America, about 93 percent of the continental population. But little progress has been made in recent decades to increase the number of animals in conservation herds, which are managed carefully for their genetic diversity and ecological roles. Most of the animals are in herds managed for commercial use.
In 2008, there were 61 plains bison conservation herds in North America containing about 20,500 animals and 11 conservation herds of wood bison, containing nearly 11,000 animals.
The IUCN report says that the survival of bison populations is affected by many factors, including limited habitat and severe winters. But the greatest challenge is to overcome the common perception that the bison — which has had a profound influence on the human history of North America, socially, culturally and ecologically — no longer belongs on the landscape.
“The decimation of the American bison in the late 1800s inspired the first recovery of bison and an entire conservation movement that protected wildlife and wild places across North America,” said Keith Aune, senior conservation scientist with the Wildlife Conservation Society. The new report could provide a new framework for inspiring a second recovery of bison and restoring functional grassland ecosystems.”
Bison have the best chance of full recovery as wildlife by being allowed to roam freely across hundreds of thousands or even millions of acres. And that’s biggest challenge for conservation biologists interested in restoring the species.
“The bison is the largest land mammal in North America, and yet it is perhaps the most neglected icon,” said Steve Forrest, the northern Great Plains manager for conservation science with the World Wildlife Fund. “These guidelines provide a road map for bringing the bison back to its rightful place as a keystone of the great plains,” Forrest said, referring to the IUCN study.