Relationships between Human Industrial Activity and Grizzly Bears

Most grizzly bears (Ursus arctos) live outside parks and reserves and often have to contend with, among other things, resource extraction industries. These activities can affect individual bears and therefore populations by: 1) causing strong, energetically expensive reactions by bears that disrupt their normal behaviour, 2) displacing bears from areas of human use, 3) altering habitats in which bears live, 4) disrupting the bears' social system, and 5) industrial personnel killing bears or increasing mortality rates indirectly by improving access for hunters, poachers, other resource users, and settlers. Grizzly bears are able to adapt to many habitat changes and a temporary increase of human presence. In most cases, increased motorized access that results in a long term increase of human activity and/or settlement with consequent increase in bears being shot is the most significant aspect of industrial developments. If an industrial activity is conducted with adequate guidelines to maintain important habitats, properly locate camps, incinerate garbage, restrict use of firearms, and close motorized access after the job is complete, the bear population probably will be maintained at a satisfactory level. Although many bears may be alive when an industry has completed its work, if access remains intact, the grizzly population is placed in a precarious position and may decrease in size and eventually be extirpated. Closing access afterjob completion is often physically and politically difficult. Industry personnel and government managers must take leading roles in planning, advertising, and implementing road closures. Cumulative effects models have been built to predict the impact of human activities on bear populations. These models are in early stages and require data to support the coefficients used and the relationships between coefficients. Then they should be tested. One significant variable the models lack is the potential for a specific activity to be the seed for blooming additional and perhaps more harmful developments. Int. Conf. Bear Res. and Manage. 8:57-64 To maintain our accustomed standard of living, North Americans require products that use vast quantities of natural resources such as timber, minerals, hydrocarbons, water, range, and soil. As increasing densities of human settlement radiated across the continent and gradually northward during the last century, most ecosystems were greatly altered by people using these resources. To maintain some areas in a relatively pristine condition, parks and reserves were established and within these, industrial activities and human settlement were strictly regulated or disallowed. Today, most of the continent has been severely altered by various resource extraction activities and large tracts of relatively undisturbed places are limited to parks and mountainous portions of the west and the north. Most individuals of each North American bear species -black (Ursus americanus), grizzly/brown (Ursus arctos), and polar (Ursus maritimus) do not live in parks or reserves and many co-exist with various human activities. Because the spread of industrial development and human settlement continues into remaining remote areas, other bears will be forced to deal with increasing numbers of people. The rise of human numbers on the continent has not affected all bear species to the same extent. Black bears have undoubtedly been influenced by urbanization, expanses of vegetative mono-cultures, and local overharvest (Manville 1983) but they have survived the spread of humanity relatively well; in some locations they may have benefited, at least over the short term (Manville l Invited paper 1983, Lindzey et al. 1986, Young and Beecham 1986, Gamer and Vaughan 1987). Polar bears are confined to portions of the continent that are inhospitable to most people and, as a consequence, the increasing human population has so far had a minimal effect on their distribution. With increasing interest in oil and minerals in the north, polar bears are now facing more temporary human residences. Of the North American bear species, the numbers and distribution of grizzlies have suffered most from the expanding human population; they currently occupy less than half their historic range and their status is tenuous south of Canada (Martinka and Kendall 1986) where these bears are classified as threatened. The grizzly bear remains vulnerable to many threats, the greatest of which are human-caused mortality and habitat modification or loss by logging, geothermal, mineral and hydrocarbon developments, water impoundments, and livestock grazing (LeFranc et al. 1987). The most secure situation for grizzly bears is a large tract of land set aside as wilderness or where wilderness has been regained by reducing human use. This management option, however, is rare and we will be forced to manage bears and people together over most of the remaining grizzly bear range. Because grizzly bear movements are extensive, to prevent further fragmentation of their range, bears and their habitat must be managed on a landscape scale often exceeding thousands of square kilometres (Schoen 1990). How the land between reserves is managed will be most important in determining the distribution and perhaps continued existence of grizzlies over the long term. Given the history of grizzlyhuman co-existence, this will be a difficult challenge. 58 BEARS-THEIR BIOLOGY AND MANAGEMENT People can affect bear populations in 5 general ways: 1) we can stimulate strong, energetically expensive reactions by bears that disrupt their normal behaviour, 2) bears can be displaced from areas of human use, resulting in the loss of habitats available, 3) people can alter the dynamics of plant and animal communities, or habitats, that bears live and depend on, 4) man can disrupt bears' social systems by forcing more bears into limited seasonal habitats perhaps causing increased intraspecific conflict, mortality and dispersal, and 5) man can cause direct mortality by legal harvest, poaching, legal and illegal nuisance bear killing or bear removal, self-defense, and research and management accidents. These 5 categories of potential impacts are often interrelated. Cumulative effects models have been built to estimate the total effects of a human activity by summing some of these potential impacts. In this paper I review the relationship between grizzly bears and human resource extraction industries by investigating the 5 main ways industries can affect grizzly bear behaviour and population trends. Some of the ideas and concepts presented are supported by very limited empirical data and should be considered only as hypotheses. They have been presented to stimulate discussion and direct future research. Solutions to the most significant problems are proposed. I thank F. Bunnell and R. Archiba~d for suggesting the topic and inviting me to present this review. A. Hamilton, J. Nagy, and D. Shackleton reviewed an early draft and made helpful suggestions. I would like to acknowledge R. Demarchi for permitting the use of his access maps and his continued support. Financial support for this review came from the National Fish and Wildlife Foundation, Shell Canada, B.C. Southern Guides and Outfitters, and the East Kootenay Fish and Wildlife Association. IMMEDIATE REACTIONS How a bear reacts to people will depend on many variables, including the type of human activity, where the interaction occurs, the distance between person and bear, the amount of cover, the individual bear's past experiences, inherited tolerance, and age/sex class. Grizzly bears are capable of at least partially habituating to human activities (K.L. Jope pers. commun.) provided the activities are frequent enough and innocuous. In portions of Glacier National Park where hiking is popular, some grizzlies have habituated to people on foot (Jope 1985) whereas in the adjacent Flathead drainage where hikers are rare and almost all carry guns (hunters), bears show stronger reactions to people on foot than to any other form of human activity (McLellan and Shackleton 1989a). In the Flathead, however, some bears have at least partially habituated to vehicles but not to the degree that bears in Denali National Park have (Tracy 1977, Singer and Beatte 1986). Similarly, radio-collared bears that were not immobilized from a helicopter but were frequently relocated from low flying aircraft can become accustomed to aircraft and may not even look up as they are circled (Blanchard 1983, McLellan and Shackleton 1989a). Due to habituation, we should expect to find bears' strongest reactions to most innocuous activities at the onset of an industrial development and their reactions to decrease with time. We should also expect bears to react less to the most common, innocuous human behaviours. Individual bears may show different responses to the same stimuli occurring in different locations. People hiking or driving where they often do will elicit milder reactions in bears than the same activity where it rarely occurs (Tracy 1977, Jope 1985, McLellan and Shackleton 1989a). The extraction phases of industries such as oil and gas, timber, and mining that result in people behaving predictably may result in fewer extreme reactions of bears than the more extensive and unpredictable seismic, mineral exploration or even timber cruising phases of development. Cover also affects a bear's reaction to people. In the Flathead, bears in timber were never known to flee from vehicles but a bear in the open almost always ran away from the vehicle to the closest timber (McLellan and Shackleton 1989a). In Denali Park, which is generally more open than southern Rocky Mountain areas, reaction to vehicles that stopped was stronger when the bears were partially screened by vegetation than when they were in the open. It was suggested that reduced security was because bears could not see clearly what the people were doing (Singer and Bea