Long-Term Gray Wolf Monitoring


The purpose of this long-term natural history study and monitoring program is to understand the wolf and to manage or restore wolf populations. It investigates survival, mortality, pack structure, territoriality, movements, scent marking, howling, predatory behavior, productivity, demography, longevity, population trends and prey (white-tailed deer) interactions on the Superior National Forest. This project is headed by the Biological Resources Division of the U. S. Geological Survey, formerly the Division of Wildlife Research of the U. S. Fish and Wildlife Service, and has been studying wolf population trend in the central Superior National Forest around Ely, Minnesota since 1968. The Superior National Forest has been a partner in more recent decades. Highlights of various aspects of the study are given below. Wolf Natural History -- When the wolf was placed on the Endangered Species List in 1967 little was known about wolf natural history. This long-term life history study investigates survival, mortality, pack structure, territoriality, movements, scent marking, howling, predatory behavior, productivity, demography, and longevity. This information is necessary to understand the wolf and to manage or restore wolf populations. Population Trend of Wolves in the Central Superior National Forest -- Population trends of wolves in unharvested populations have seldom been studied, and little is known about factors affecting wolf population trends. NPWRC's study of wolf population trends in the central Superior National Forest seeks to determine these factors and how they affect the wolf population. Begun in 1966, this study is one of only two such long-term investigations. Results from this investigation provide a gauge against which trends in reestablished wolf populations can be measured. Effects of Canine Parvovirus and Other Diseases on Wolves -- Canine parvovirus (CPV) is a relatively new disease of domestic dogs but has also spread to wildlife. CPV has the potential for affecting wolf populations because of its tendency to kill pups less than three months of age. CPV was first found in wolf populations in the mid 1970's and has retarded wolf recovery in some areas for certain periods. This study examines the relationship between wolf population parameters and rate of exposure of wolves to CPV. In addition, it examines other diseases and their effects on wolves. Relationships Between Deer Movements, Survival, and Wolf Predation -- This study examines spatial and temporal variations in radio-collared deer killed by wolves by comparing current locations of wolf-killed deer to those documented during 30 years of sampling to assess the long-term spatial dynamics between deer and wolf packs. Daily and monthly movements, natal dispersal, and migrations between seasonal home ranges vary in their effects on predisposing deer to wolf predation. Effect of Wolves on Deer Populations and Deer Hunting -- Because wolves prey primarily on white-tailed deer in the Lake Superior states, some members of the public perceive the wolf as a competitor to human hunting. This perception affects human attitudes towards wolves, influencing both wolf recovery and management of recovered wolf populations. This study examines the relationship between wolf density and deer numbers, as well as the age, sex, and condition of deer killed by wolves and the effect of snow conditions on the wolf-deer interactions. Deer Mortality -- Measuring rates and causes of radio-collared deer mortality is necessary to understanding the influences of wolf predation in deer population dynamics. NPWRC is monitoring deer survival and mortality throughout the year to be able to assess both seasonal and long-term deer population dynamics. Biologists relate these rates to winter severity and changes in deer and wolf numbers. Deer Movements -- Many northern white-tailed deer seasonally migrate between summer and winter home ranges, although the proportion of different populations that migrate varies. This variation can determine numbers of prey seasonally available to wolves and can impact wolf-pack dynamics and movements. Exploratory movements and natal dispersal by yearling deer also influence distribution of prey for wolves. NPWRC scientists document various types of deer movements by radio-tracking individual deer to increase our understanding of natal dispersal, migration, gene flow, and effective population size.


For monitoring wolves and their prey (white-tailed deer), the basic techniques involve live-trapping and radio-tagging wolves during summer and fall (deer during the winter), aerially observing their pack sizes during winter, and determining their territory sizes by aerial radio-tracking. A wide variety of other methods are used to study wolf natural history. Selected publications, from among the many generated by this project, describe other methods are listed at: http://npwrclib.cr.usgs.gov/starweb/pubsearch/servlet.starweb ?path=pubsearch/pubsearch.web.


An aerial survey of radioed and non-radioed wolf packs in a 2,060-sq-km area of the central Superior National Forest showed that about 97 wolves were present, or 4.0/100 km square. Eight radioed packs and six non-radioed packs of 2-10 individuals used all or part of the census. Some 47 wolves from the radio-marked packs, and 35 in the non-radioed packs were attributed to the census area, for a density of 4.0 wolves per 100 km sq. Thus this yr is 15% higher than last yr and is the highest density I have recorded in our study area. (Mech person. Comm)


For background info on the study:http://www.npwrc.usgs.gov/about/factsheet/mammals.htm


Collection Agreement


Voyageurs National Park , University of Minnesota , North Central Research Station , USDI USGS BRD - Northern Prairie Wildlife Res. Ctr.-MN Wolf Project , USDI USGS BRD - Northern Prairie Wildlife Res. Ctr.-MN Wolf Project , USDI USGS BRD - Northern Prairie Wildlife Res. Ctr.-MN Wolf Project


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The gray wolf is a species emblematic of the Northwoods and of great public interest to visitors to the Superior National Forest. The information that comes from this project is funneled to the public through the International Wolf Center, a popular tourist destination in Ely, MN, where environmental education is a key goal. For learning resources about wolf: http://www.wolf.org/wolves/index.asp