Morphological analysis of wolves associated with woodland caribou in late succession boreal coniferous forests north of the commercial cut line and those associated with moose in early succession boreal deciduous forests south of the commercial cut line were studied in Ontario. So-called "moose-wolves" could readily be distinguished from "caribouwolves" in both genders using a few morphological measurements. Wolves associated with woodland caribou were significantly smaller in most measurements, and increased in size within seven years post-harvest as moose totally replaced caribou in the ecosystem. Whether this change in wolf morphology is related to micro-evolutionary change, the migration of larger "moose-wolves" into the area, or both, remains unclear.

the literature indicates a continued controversy whether ungulate populations are controlled from the bottom-up or the top-down and whether wolf predation is benefi cial removing sick and unfi t in-p or the top-down and whether wolf predation is beneficial removing sick and unfit individuals or detrimental, driving populations into the so-called "predator pit". a macro-ecological approach was used to address these questions supporting the following conclusions: ungulates have evolved at the biome spatial scale, late and early succession specialists occur in each biome, one is larger and one is smaller, historically wolves occurred in all North american biomes as primary predators of ungulates, wolves specialize on the most common ungulate species, wolves change morphologically in relation to the size of their primary prey, pack size changes in relation to the size of their primary prey, wolf predation can be beneficial or detrimental depending upon the numerical and size relationship between the ungulate species in the system. Climate changes such as fire, drought and insect infestation will create early successional habitat increasing early successional specialists numbers and decreasing late successional ungulate population numbers. Bottom-up and top-down forces exist in all populations where wolves occur and managers need policies that support the smaller sized ungulate in the ecosystem, if they want to maintain both species at stable or increasing population levels.