Arguments about the relative merits of the current and alternate proposed Pacific Northwest Trail (PNT) routes for grizzly bear conservation center on costs and benefits of the two routes vis-ŕ-vis prospects for and impacts on the bear population. Parenthetically, as Wayne Kasworm cogently noted, a better scenario than either would be no PNT at all. My take on cost-benefit is as follows:
The current proposed route transects some of the most productive and secure habitat in the Yaak, including productive open habitats where displacement of bears is predictably greater. Moreover, given the proportionately much higher levels of bear activity here compared to along the Kootenai River corridor, more bears will predictably be affected.
The alternate route following the Kootenai River transects an area that is already the least secure and least used by bears of any in the Cabinet-Yaak ecosystem. The upshot is that few bears would be adversely affected by hikers on the alternate route.
The key to long-term growth of the Yaak population is survival and productivity of females. Adult females currently make much greater use of the proposed route versus the alternate Kootenai River route. Barring anomalous conditions along certain coastal salmon spawning streams, ample research has shown that adult females with young are the most reactive of any bears to people and the most likely to aggressively defend space when surprised. The upshot is that adult females will not only more likely be adversely affected by hikers on the current proposed route, but also pose more of a threat to human safety.
Wayne Kasworm and others argue that placement of the PNT along the Kootenai River in an area that is already a fracture zone would significantly impair efforts to mitigate current impediments to connectivity. This assumes that the trail and trail-related traffic would add significantly to impediments already posed by the Highway 2/BNSF travel corridor as well as humans in residences and on secondary roads. Almost certainly, any added impacts attributable to addition of the PNT to the Kootenai River corridor would be trivial in comparison to current impacts. Moreover, mitigation of those trivial impacts would likewise be trivial in comparison to the current urgent need to install a highway/railway crossing infrastructure, remove and mitigate human-related attractants, control human access, and effectively enforce laws. Addition of the PNT to this mix would be such a comparatively minor impact as to be inconsequential.
Wayne Kasworm argues that hikers need to transit the Yaak area “as quickly as possible,” implying that transit speed alone determines likelihood that hikers will adversely affect bears. This argument is misleading in that transit time is only a small factor in determining odds of an encounter. The more important factor is levels of bear use in any given area, which are currently orders-of-magnitude greater along the proposed PNT versus the alternate PNT route.
Putting all of this together leads to an inescapable conclusion. The current proposed route for the PNT will have substantially greater impacts on the Yaak grizzly bear population compared to the alternate proposed route along the Kootenai River. This conclusion holds for both the short- and long-term. To conclude otherwise requires that we ignore or distort most of what we know about grizzly bear behavior and the distribution of grizzly bears and grizzly bear habitat in the Yaak area.
— David Mattson, PhD
David Mattson retired from the U.S. Geological Survey in 2013 and from a teaching position at Yale University in 2015. he and his wife started an independent effort, Grizzly Times, featuring a web site that provides information relevant to grizzly bear conservation. He lives south of Livingston in Paradise Valley.