The calls of coquí frogs resound through the forest of Waimānalo, echoing off the nearby valley walls.
Amid this chorus, Ryan Chang’s ears have honed in on a single frog, croaking somewhere in the broad leaves of a small octopus tree. He turns off his headlamp and whistles to coax the frog out of its hiding spot.
Chang can make a nearly perfect impression of the coquí’s distinctive call, a loud koh-kee from which the frog gets its name. But this frog isn’t buying it…