1. U. S. Geological Survey, Eastern Ecological Science Center Silvio O. Conte Research Laboratory Turners Falls Massachusetts USA
2. US Forest Service, Northern Research Station Amherst Massachusetts USA
3. Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, Franke College of Forestry and Conservation University of Montana Missoula Montana USA
4. Department of Environmental Conservation University of Massachusetts Amherst Massachusetts USA
5. Department of Mathematics and Statistics, Williams College Williamstown Massachusetts USA