Sometime around the beginning of the climb up the remote Mirror Plateau, I began to regret our decision to do another big hike. Between the cloud of insatiable mosquitoes in erratic orbit of my head, the sudden emptying of the sky’s hail on our little section of meadow and the lack of any sort of a trail to lead us through the increasingly slippery web of fallen logs and branches, I momentarily questioned my ability to complete our mission. The route we forged took us forever upward, steeply, in order to avoid the densest of the logjams and stay out of the open fields when lightning was near. Our only means of maintaining a somewhat forward direction was to traverse around the ridge, staying well below the summit. However, that also meant that we had to scramble over the plethora of downed trees and splintered trunks and limbs covering the area, and we were in a rush to move on. The Mirror Plateau is a park Bear Management Area, restricted to day use only in order to reduce human-related impacts on bears in high-density grizzly bear habitat.
We picked our way through the wet logs in a careful hurry—each slight slip reminding us of how easy it would be to get impaled by one of the fractured limbs protruding from every direction. Although it’s located in the center of Yellowstone, one of the most visited national parks in the U.S., the fact that no roads or trails cross the plateau keeps it remote and virtually untouched by humans. In the event of an accident, we were many miles and even more hours from the nearest access point, making a rescue highly unlikely. After 16 hours, we found a decent tree for a bear hang, set up camp and passed out. We had four consecutive days of getting our asses thoroughly kicked under our belts, and many more ahead. But we weren’t on a pleasure hike. My partner and I were on a scientific mission, linking two major “gems” of core wildlife habitat, collecting data along America’s best hope for a carnivore superhighway.
The Northern Rockies of the United States evoke a feeling of true wilderness. With the exception of the passenger pigeon, the area is still home to all of the native vertebrates that were here when Lewis and Clark passed through more than 200 years ago. Here, the lynx, wolverine, wolf, badger, black bear, grizzly bear and puma still reign. Within this region lie two of the most intact and important ecosystems in the world’s temperate zone: the Greater Yellowstone Ecosystem and the Salmon-Selway Ecosystem, including the Frank Church–River of No Return Wilderness in central Idaho. Because the Northern Rockies remain so remote and largely unaffected by human development, scientists believe that these areas may be the last remaining hope for the existence of a viable carnivore community in North America. However, the carnivores in the region are under a great and ever-increasing threat. With rapidly expanding human populations, their habitat is becoming extremely fragmented, threatening their ability to move freely between protected areas.
When populations of animals exist in isolated ecosystems, they are left without the ability to maintain genetic diversity. Simply put, when a species can no longer move to new habitats, its long-term chances of survival plummet. Brent Brock, a landscape ecologist with the Craighead Institute, which has been at the forefront of the connectivity movement for the better part of 40 years, describes the need for genetic diversity as the equivalent of having a really big Swiss army knife: As an environment changes, having the capacity to use a variety of tools greatly increases odds of survival. Genetically homogeneous populations have all their eggs in one basket, so to speak, and for animals like the bears in the Northern Rockies, that basket is already tenuously perched on an edge. Habitat loss and disruption have been widely acknowledged as primary causes of the decline and ultimately the extinction of numerous animals throughout the world, and in order to preserve the legacy of the charismatic carnivores found in North America, scientists must understand the way wildlife species move between protected wilderness areas. This is where we came in.
Following the most likely routes that bears would take between the Greater Yellowstone and Salmon-Selway ecosystems, our mission was to travel from the perspective of the wildlife, allowing for a unique opportunity to identify the conditions of and any threats to key habitat areas. As we trekked, we sought to document the presence of various species through the collection of DNA hair samples and by recording locations of scat, tracks, rubs and other animal signs we encountered along the way. We departed from the eastern edge of Yellowstone National Park in early July 2010 and spent the next 30 days exploring the area, extending more than 520 miles to the west, through some of the most remote and rugged mountains in the lower 48 states.
