Department of Natural Resources
Moose almost became extirpated from Michigan's Upper Peninsula by the 20th century. Habitat changes, human exploitation, brainworm and wolf predation were primary factors thought to contribute to the decline in moose. A translocation of 69 moose from Isle Royale to the Upper Peninsula during 1934-37 resulted in frequent sightings initially. By the 1940s, the moose population apparently had declined to a low level, and the relocation effort eventually was judged a failure.
By the 1970s, the white-tailed deer population in the Lake Superior watershed in the Upper Peninsula had declined drastically, and biologists in the DNR began to consider a moose translocation to fill a vacant niche. Aerial and ground inspections by Ontario moose experts confirmed suitable habitat. In 1985 and 1987, the DNR translocated 61 moose from Algonquin Provincial Park in Ontario, Canada, to northwest Marquette County.
The moose reintroduction project represented a monumental undertaking in terms of equipment, manpower, distance involved and costs. Resources of the DNR and the Ontario Ministry of Natural Resources, as well as monetary contributions from private citizens and organizations, were invested. The operation was highly visible in the scientific and sporting communities, and received widespread coverage by the news media.
The goal of Michigan's moose management program is a self-sustaining population of free ranging moose. Specifically, the objective of the program was to produce a population of 1,000 moose by the year 2000.
During the 1990s, moose population estimates derived by a "bookkeeping" or population model, and a newly developed aerial census technique produced disparate results. Despite a detailed reevaluation of these two techniques, biologists could not explain the discrepancy. The reevaluation process revealed biologists have only a rudimentary understanding of the population dynamics of moose in the Upper Peninsula, and that current data sources are insufficient for reconciling differences in population estimates.
Despite the differences in moose population estimates, it is clear the population objective of 1,000 moose by 2000 will not be achieved. Although it may not be possible to retrospectively determine why the moose population did not grow at the rate expected, there is a need to understand the potential for future growth of the moose herd in order to establish a new and realistic population objective.
The moose population assessment has two main objectives. The first objective is to describe the population dynamics of moose in the western Upper Peninsula of Michigan. Three factors cause populations of wild animals to change in number: (1) births, (2) deaths and (3) immigration/emigration (dispersal). The focus of a population dynamics study is to measure rates of birth, death and dispersal, and relate them to environmental influences. Determining rates of birth, death and dispersal will allow biologists to calculate the rate of increase of the moose herd. This information is essential for developing a scientifically based population objective.
Evaluation of the birth, death and dispersal rates also will help biologists key in on the factors limiting the growth of the population. Examples of factors that may limit moose populations include diseases, parasites, nutrition and predation. Once limiting factors are identified, biologists can determine whether it is feasible to influence those factors through management. Intensive monitoring of radio-collared animals is a well-accepted scientific method of acquiring this information.
The second objective is to develop and evaluate techniques to estimate the size of the moose population in the western Upper Peninsula of Michigan. A common problem with most wildlife population estimation techniques is that validation usually is not feasible. To validate a population estimation technique, the estimate must be compared with the true population size, information that rarely exists. Thus, biologists commonly use several independent estimates of population size. If these independent estimates show similar results then biologists have more confidence in the estimates. Currently, the DNR has two independent estimates of moose population size (aerial survey and population model) but they do not agree. Thus, there is a need to continue to develop and evaluate techniques to estimate the size of the moose population in the western Upper Peninsula of Michigan.
Completion of this six-year study will allow DNR biologists to develop a scientifically based objective for the moose herd. Wildlife biologists will understand the potential for growth of the herd, and by identifying and understanding limiting factors, biologists will know whether the population's growth rate can be influenced through management. This information is important so the public can be informed of the herd's potential and public expectations can be balanced with biological potential. This includes the ability to evaluate the potential for establishing a hunting season. In addition, other wildlife managers contemplating moose reintroduction programs look upon the DNR moose reintroduction program as a primary source of information.
This study is a cooperative project between the DNR and Michigan State University. Funding for this project is provided by Federal Aid in Wildlife Restoration, Pittman-Robertson Project W-127-R and the Michigan Involvement Committee of Safari Club International.