Traffic at Norris Junction. Based on several data points, visitation to Yellowstone is exceeding the park's ability to deal with the growing masses and is past the point of resource sustainability. Under Wenk's leadership, Yellowstone has taken a serious look at carrying capacity issues and the recognition that in order to maintain the integrity of Yellowstone there must be discussions about limits to the number of people during the crush of peak tourist season. In some ways the has already happened with winter use in Yellowstone and caps put on snowmobiles. Photo by Jacob W. Frank/NPS