William A. Gould,^1,2 Grizelle González,¹ Donald A. Walker,³ Chien-Lu Ping<sup>4

1</sup>International Institute of Tropical Forestry, USDA Forest Service, Río Piedras, Puerto Rico 00926-1119
²Corresponding author: wgould@fs.fed.us
³Institute of Arctic Biology Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, Alaska 99775, U.S.A.
⁴Palmer Research Center, University of Alaska Fairbanks, 533 East Fireweed Avenue, Palmer, Alaska 99645, U.S.A.