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The whole concept of subspecies is a contentious one deriving from the human attempt to categorize natural differences between organisms. On the subspecies scale, the distinctions have been very subjective and questionable in value (Wilson and Brown 1953; Mayr 1954).

In the case of the wolf, this confusion was addressed in Nowak's (1995) revision of wolf taxonomy in North America. Nowak lumped the 24 subspecies into only 5. Because of the wolf's great mobility (Van Camp and Gluckie 1979; Fritts 1983; Ballard, Farnell, and Stephenson 1983; Gese and Mech 1991; Boyd et al. 1995), it was clear that the North American wolf population was mixing greatly, thus tending to refute the concept that the population comprised of large numbers of physically different groups of wolves. Nowak's 5 subspecies made much more sense than the original 24.

The U.S. Fish and Wildlife Service responded to the Endangered Species Act by setting up a team for each species on the list to plan their recovery. In the case of the wolf, teams were established at first for each of the 24 wolf subspecies that may still have had members remaining in the 48 contiguous states, including the eastern timber wolf (Canis lupus lycaon), the Mexican wolf (C. l. baileyi), and the northern Rocky Mountain wolf (C. l. irremotus). In addition, the red wolf (Canis rufus), a taxonomic enigma to this day (Nowak et al. 1995), was granted its own recovery team. The teams were made up of experts on the wolf and administrators from various state and federal agencies who would be involved in the recovery of the specific animal.

By 1978, the U.S. Fish and Wildlife Service had changed the way it listed wolves as endangered. All remaining wolves in the 48 contiguous states were listed, rather than the individual subspecies. Thus, regardless of subspecies, wolves anywhere in the 48 states were on the list. However, the recovery teams for each subspecies retained their names, and the plans they developed retained the names of the subspecies.

Nowak's (1995) taxonomic revision necessarily redrew the lines separating the subspecies, and his data showed that the eastern race of wolf, the eastern timber wolf (C. l. lycaon), had inhabited the northeastern part of the United States east of Michigan. Under the pre-1995 classification, however, the eastern timber wolf range had extended almost to the western border of Minnesota, thus including Michigan, Wisconsin, and most of Minnesota in its range.

However, the only remaining wolves in the eastern United States when the animal was placed on the Endangered Species list were those in Minnesota and on Lake Superior's Isle Royale (a part of Michigan). Thus the Eastern Timber Wolf Recovery Team, which had examined the status of this race of wolf in all its former range, had decided that the best region in which to promote wolf recovery was Minnesota, Wisconsin, and Michigan.

There were several reasons for this decision. First, wolves had inhabited Michigan and Wisconsin until the 1960's (Hendrickson et al. 1975; Thiel 1993). Second, both northern Michigan and Wisconsin included large amounts of wilderness or semiwilderness in public holding, and Minnesota still harbored several hundred wolves (Cahalane 1964, Mech 1970). Third, there was reason to believe that wolves from Minnesota could disperse into Wisconsin and Michigan (Mech and Frenzel 1971). Fourth, there was confusion about whether the wolf that occurred originally in the southern Appalachians was the eastern timber wolf or the red wolf. Finally, state agencies in Maine and New York had responded negatively to queries by the Eastern Timber Wolf Recovery Team as to whether they would consider restoring wolves to their states (U.S. Fish and Wildlife Service 1978).