WOLVES AND MOOSE OF ISLE ROYALE
Image courtesy of UMFK
While hiking and canoeing through Algonquin Provincial Park in my younger years, my biggest thrill was to hear the howls of wolves or catch the sight of an animal. While in the Arctic, I watched packs of wolves relentlessly pursue caribou herds over the tundra. Despite studying a diverse and distinct group of animals over the years, I am very much fascinated with wolves. I think the most remarkable long-term predator/prey study—celebrating 50 years of monitoring—is the interrelationship that exists between the wolf and the moose on Isle Royale. The island is a national park and serves as a natural laboratory in Lake Superior. The wolves prey on moose, and the moose have no other predators in the ecosystem. Interestingly, the island has afforded biologists with a unique opportunity to study the complex interactions between these species, while being relatively unscathed by the impacts of humans. While many popular articles have described a balance between predator and prey, the system has not exactly followed this design. Additionally, there are several new environmental factors that have added to the unpredictability of this balance. Indeed, the isolation of the island has allowed researchers to discover new information about the ecology of this partnership between wolves and moose. The story of this relationship is unique and fascinating, and must be revealed.
Stephen Hansen, PhD, Assistant Professor of Biology & Environmental Studies
Growing up in the city of Toronto, in southern Ontario, I spent my summers as a naturalist while exploring Algonquin Provincial Park. My parents had a summer cottage near the park's southwest boundary, which afforded me ample opportunity to hike and canoe throughout the park and study its abundant wildlife. Fittingly, I graduated from the Faculty of Forestry at the University of Toronto in 1978. While in college, I was part of a student team that undertook the crafting of a management plan for the Petawawa Research Station, near the eastern boundary of Algonquin Park. I was responsible for the wildlife section. During my undergraduate degree, I worked for Kimberly Clark during my summers and was offered full-time employment upon graduation. However, I decided to pursue a career involving wildlife and my passion certainly lead me in a new direction.
I spent seven years as a research biologist in Churchill, Manitoba. This opportunity provided me with an extensive background in Arctic research, including involvement in a number of environmental studies on Arctic wildlife, including the polar bear, white whale, Arctic fox, wolf, ringed seal, and caribou. These studies provided baseline information necessary for the conservation and management of these species.
During my first year in Churchill, I was part of a team that investigated temperature regulation in polar bears. In subsequent years, I was involved in studies of denning and locomotory energetics, telemetry work on bears, and the effects of disturbances on denning bears. I collaborated setting up a program with the Manitoba Provincial Government to acquire Arctic fox carcasses from local trappers in order to determine the age and sex distribution of the population, while also investigating evaporative heat loss in Arctic fox during this time. Additionally, I was involved in a field study on caribou in the Churchill Wildlife Management Area, now called Wapusk (the Cree word for "white bear") National Park. With a mixture of tundra and sub-arctic terrain, the park also hosts one of the world’s largest known polar bear maternity denning areas. I followed caribou herds by dog team and camped-out on the tundra.
While in Churchill, I also led specialty tours, including historical tours at Fort Prince of Wales, bird tours, boat tours to view whales, and wildlife tours. While on a whale tour, I noticed a female bear feeding on a whale carcass along the shore of the estuary. About 150 feet from her, I thought her cub was curled up and sleeping. However, as we approached, the animal arose and we discovered that it was a white wolf. It was probably just waiting for the bear to leave the carcass. More often, I would take people out on the tundra to see Arctic wildlife, especially bears. Needless to say, the potential to encounter bears in close proximity was always a high probability. In fact, in the town of Churchill, as soon as it gets dark a siren goes off and all children are required to be off the streets. I remember being out in a tracked-machine along the Hudson Bay coast with a group of hunters and being hit by a severe white-out. While unable to move because of low visibility and trying to secure all exposed openings (e.g. radiator grill) from snow entry, I almost became a bear's meal. While rounding the corner of the machine I bumped into a standing (about 9 or 10 feet high), 800–900 pound polar bear. Falling back-wards, while trying to obtain my revolver from under my parka, the bear lunged towards me. Suddenly, I saw a shadow hit the bear’s upper neck area and bump the bear's head into the side of the machine. It was my trusty dog, Kojo (means "copilot"), a large Alaskan malamute. The bear was so startled that he took off running. My dog had belonged to a bush pilot and was often strapped into the copilot's seat. (Unfortunately, the pilot, Kojo's first human caretaker, was severely burned in a plane crash and asked that I take his dog. It was not my dog's first close encounter with a polar bear; I was told that he fought it out with a bear that was trying to steal his food on the back porch of their family home. He survived, but had to be flown out for sutures.)
I obtained a Master of Science degree in Biology at Laurentian University in 1987. For my degree, I studied the distribution and abundance of white (or beluga) whales in relation to various environmental parameters (e.g. water temperature, salinity and turbidity) in the Churchill River estuary and adjoining coastal waters of Hudson Bay. Over three summers of study, there was a high correlation between both whale abundance and distribution with water temperature. While these results do not indicate the physiological reasons for summer estuary use, it seems reasonable to suggest that the whales are there for the thermal advantage of warm water for both molting and growth of their calves. These results provided vital information on the biology and management of white whales. Additionally, the results provided valuable insights into the potential impact of river diversions on this species.
In 1995, I completed my Ph.D. in zoology at the University of Guelph, with my doctorate research concentrated on how environmental factors and energetic considerations influence seal distribution and abundance. My results indicated that that warm ambient air temperature during the reproductive phase of harbor seals' life cycle (i.e. pups) delineates the southern extent of the species' breeding distribution. Conversely, my results also indicated that cold ambient air temperatures during the reproductive phase (i.e. pups) of grey seals' life cycle delineates the northern extent of that species' breeding distribution. Importantly, my study supports the conclusion that metabolic rates of seals are, for their size, similar to those of other mammals. This research elucidates the energy requirements of marine mammal populations and has profound implications for the assessment of potential interactions between marine mammals and fisheries.
Since completing my doctorate, I have taught at a number of institutions in both Canada and United states, while developing a multi-faceted research program. I have continued with the same research theme by concentrating on the energetics, behavioral and physiological ecology, genetic diversity, and population dynamics of several select vertebrates, in relation to environmental and climatic changes. This information has certainly enhanced our knowledge of the ensuing factors (both biotic and abiotic) that ultimately affect species distribution and abundance. An integral part of my ongoing research also has been focused on inventorying and quantitatively assessing the habitat of selected species over time, so that animal behavior, ecology, abundance and distribution could be correlated with changes in the habitat as influenced by environmental and climatic change. While in Michigan, I conducted two studies that directly parallel my research interests: the seasonal variation in the daily movements, home range and territory of male snapping turtles in relation to habitat as determined by GIS and; the seasonal and annual variation in home range size, movements and habitat use patterns of black bear in the Eastern Upper Peninsula of Michigan, as determined by GPS and GIS, (both studies done in collaboration with Michigan Department of Natural Resources). The terrain on the southeast shore of Lake Superior is quite unique, and is an environment characterized by long, interconnecting chains of finger-lakes and bogs between forested beach ridges, which may influence and/or modify home range size, movements and habitat use patterns of various animals as distinct from other more inland areas.
More recently at University of Maine at Fort Kent, I have initiated several studies that have formed the basis of several of my classes (e.g. field ecology). Since 2004, I have been investigating (in collaboration with IFAW) [note: what is IFAW?] the threat of bio-invasive fish species (i.e. muskellunge and small mouth bass) moving into the Fish River System and the impact that climatic change and land-use practices are having on these cold water fisheries (i.e. trout and salmon). Preliminary results from these studies indicate that many of the lakes in this system are impaired and not suitable habitat for cold water fish species. Over the last year, I have been trying to determine which canid species inhabit the Maine/New Brunswick border area using DNA and morphological analysis. This fall, I initiated a study on winter ticks and their potential impact on the moose population in northern Maine (in collaboration with the Maine Medical Center). This parallels another two-year study on deer ticks in Northern Maine. For the past three summers, several of my students have studied the Furbish lousewort through independent studies. This plant is on the endangered species list of both the state and federal governments and is indigenous only to the St. John Valley. Therefore, the long-term goal of my research is to provide insight into the possible effects that environmental and global change might be having on the distribution and abundance of this plant.
All images in extended bio from the US Fish and Wildlife Service's National Image Library.