Environmental Studies Program



Cody Willers

Date of this Version



Environmental Studies Undergraduate Student Thesis, University of Nebraska-Lincoln, 2022


Copyright 2022, Cody Willers


A comprehensive literature review of the topic of the reintroduction of the grey wolf (Canis lupus) into the lower 48 states has been conducted to determine the viability of the grey wolf as a method for managing the overgrowth of medium to large ungulate populations. Due to the overgrowth of medium to large ungulate populations without the presence of the grey wolf, detrimental environmental impacts were being seen on many ecosystems such as Yellowstone in North America. Through predation and the fear of predation, the presence of the grey wolf in these ecosystems can provide a solution to the negative environmental impacts associated with the overgrowth of medium to large ungulates. After conducting a comprehensive literature review it is shown that the presence of wolves helps reduce disease within ungulate populations and improve the health of plant species in that ecosystem. Both the flora and fauna of ecosystems impacted by the presence of the grey wolf show positive results in the long-term health and sustainability of these species. Species such as moose show populations with reduced disease with the predation of wolves due to selective predation by wolves. Tree species such as Aspen and Willow show a decrease in browsing and an increase in diameter breast height, while also expanding the size and health of their stands. The long-term presence of a healthy and sustainable wolf population has been shown to and could continue to show positive results on the health of the flora and fauna of their respective ecosystems.