1. U.S. Geological Survey, Oregon Cooperative Fish and Wildlife Research Unit, Department of Fish and Wildlife, Oregon State University Corvallis Oregon USA
2. Oregon Cooperative Fish and Wildlife Research Unit, Department of Fish and Wildlife Oregon State University Corvallis Oregon USA
3. Oregon Department of Fish and Wildlife Corvallis Research Laboratory Corvallis Oregon USA
4. U.S. Geological Survey, Oregon Water Science Center Portland Oregon USA