Photography levonorgestrel birth control side effects The plains coquí is an endangered Puerto Rican frog named for its unique “co-kee” call. The ARBIMON software has been fed a little bit of data about its characteristic sound pattern, and any time the small, yellow toad’s call is registered by the recorder, it is automatically picked out and cataloged. In their new paper, Aide and his colleagues listened to the plains coquí for five years. The audio analysis showed that the frog calls declined for four straight years, and recovered in the fifth.