The current configuration of National Parks, wilderness areas, and other protected habitat in the Northern Rockies of the Western United States may be insufficient to allow viable populations of native species to exist 'in perpetuity'. Synthesis of existing knowledge is currently underway to address this question, and is being carried out by a variety of academic institutions, government agencies and conservation groups. From a conservation standpoint, the sensible strategy is to ensure that we err on the side of conservation; no further degradation of wildlife habitat is allowed to proceed until it is scientifically determined how much habitat is adequate and where critical habitat is located.

If we allow too much habitat to be altered so that it is unavailable for wildlife, biodiversity will be diminished, natural systems will become greatly simplified and destabilized, and a new equilibrium point will be reached with fewer species, less stability, and diminished renewable resources such as clean water, game animal and bird populations, sport fish populations, and other, more intangible values.

The location, size, and habitat components of the currently protected National Parks and wilderness areas indicate that the best conservation strategy is to design a network of core reserves, connected by functional wildlife linkage corridors. This is the best reserve design possible at this stage of habitat fragmentation and if properly configured should prevent further fragmentation and insularization. This network should be designed along the Biosphere Reserve model with central cores of undisturbed habitat surrounded by buffer zones of limited human disturbance. Corridor connections should also be designed in this fashion with core 'strips' of protected, undisturbed habitat flanked by buffer zones of limited disturbance

One important variable affecting habitat suitability for many wildlife species is proximity to roads. Scientific studies in a variety of habitats have demonstrated that grizzly bears, wolves, mountain lions, and other wilderness species will avoid roads. Whether the road is used often or not doesn't seem to make any difference; if an animal encounters traffic, or other disturbances, on a road once, it is likely to avoid that area in the future. Obviously, roads provide easy access for hunting and other recreation and increase the probability that a large carnivore may encounter humans. Whenever people and dangerous predators come into contact, the predators ultimately lose because the bottom line is that humans are the dominant species.

Several studies in Northern Montana and in Yellowstone have found that grizzlies under-utilized areas within 500 m. of open roads. (Aune 1985, Mattson 1987, Archibald et. al 1987, McLelland and Shackleton 1988, Aune and Kasworm 1989, Kasworm and Manley 1990, Mace and Manley 1993). This avoidance occurs even at low levels of traffic and does not vary substantially with traffic levels or with the type of road surface. Grizzlies also under-utilize habitat where open road densities exceed 1.0 mi/sq. mi. and it may take several generations (20+ years) for grizzlies to respond to road closures (Mace and Manley 1993). In Scandanavia, observations of bears signs are negatively correlated with roads (Elgmork 1978).

Grizzlies also avoid other types of human developments and activities. Gunther (1984) in Yellowstone and Elgmork (1983) in Scandanavia found lower than expected use of bear habitat within 400-2000 meters of back-country camp sites and cabins. Bears tend to forage in back country areas at times when humans are less likely to be present (Olson et. al. 1990. Gunther 1984). Grizzlies in Northern Montana will avoid cutover forests for up to 30 years (until vegetation has reached a more useable stage) (Waller 1992). Grizzlies substantially under-use habitat near town sites and major recreational developments in the Yellowstone ecosystem. Areas up to 4-5 km away are avoided, especially during daytime: daytime use is reduced by 46-94% below other areas depending upon the season, food, and type of development (Mattson 1987, Mattson and Knight 1992, Reinhart and Mattson 1990).

Mattson (1993) developed a rationale proposing that secure habitat for grizzlies, particularly females with cubs, should average less than 0.26 miles of road/square mile of habitat. This road density standard is recommended by Craighead et. al. (1995) and is included as a management reccommendation by Bader et. al. 1996.

On the other hand, there are instances where wildlife species, including carnivores, will use remote roads for travel corridors or for hunting. The important variable seems to be human use of roads: if humans are present, even sporadically, wildlife will tend to avoid the area. If roads are effectively closed to vehicles, and humans do not travel by other means, many species of wildlife will use remote roads just as they use game trails. However, more work needs to be done to determine thresholds of disturbance for different species.

Critics of wilderness protection don't seem to realize that this roadless network comprises less than 5% of Montana's land area.

Corridor analysis looks at the presence of roads as well as other habitat variables.