Endangered Species Law & Policy

The Fish and Wildlife Service (Service) recently announced  (pdf) a proposed rule to reclassify the wood bison (Bison bison athabascae) from endangered to threatened under the Endangered Species Act (ESA). After completing a 12-month status review, the Service found that threats still affect the wood bison, with the largest threat being the loss of habitat caused by agricultural development, the presence of diseased wood bison and cattle herds on habitat that could be restored with disease-free herds, and the commercial production of plains bison in historical wood bison habitat. However, the Service found that these threats were not of sufficient imminence, intensity, or magnitude to indicate that the wood bison is presently in danger of extinction given the increase in the number of herds and population sizes, the ongoing management of the species, and protections provided by law. They therefore found that the wood bison is not endangered. Because threats to the wood bison still exist, however, the Service determined that the reclassification of the wood bison from endangered to threatened was warranted.

The wood bison is a relative of the American plains bison. Historically, the wood bison occupied Canadian ranges north of the plains bison. All wild wood bison presently are found in northwestern Canada. While woods bison populations were once estimated at about 168,000, the subspecies was nearly eliminated by the late 1800s. Like the plains bison, overharvest is estimated to be the major cause for the wood bison’s decline.

ESA section 4(f) generally directs the Service to develop and implement recovery plans for endangered and threatened species, but no such plan has been instituted for the woods bison because no wild populations currently exist in the United States. However, in Canada, the National Wood Bison Recovery Team (NWBRT) published a national recovery plan. This plan established four primary goals: (1) reestablish at least four discrete, free-ranging, disease-free, and viable populations of 400 or more wood bison in Canada; (2) foster the restoration of wood bison in other parts of their original range and in suitable habitat elsewhere; (3) ensure that the genetic integrity of wood bison is maintained without further loss as a consequence of human intervention; and (4) restore disease-free wood bison herds.

In 1978, there was only one free-ranging, disease-free herd with 300 individuals. However, a status review in 2000 revealed that the number of disease-free herds had increased to six, and the total population had grown to approximately 2,800 individuals. Since 2000, an additional disease-free, free-ranging herd has been established, bringing the total number of herds to seven and the total number of disease-free, free-ranging wood bison to approximately 4,400. Four of the seven existing herds have populations of 400 or more, thus meeting the NWBRT’s first recovery goal. There are also four captive herds that have been established, though only three of those herds are currently viable.

The NWBRT previously petitioned the Service to reclassify the wood bison from endangered to threatened on November 26, 2007. After issuing a 90-day finding  (pdf) concluding that the petition presented substantial scientific and commercial information indicating that reclassification may be warranted, the Service initiated a status review. The proposed reclassification of the wood bison constitutes the Service’s 12-month finding on the petition to reclassify. The Service is seeking public comments on the proposed rule. Written comments must be received by April 11, 2011, and written requests for a public hearing must be received by March 25, 2011.