Changes in vocal repertoire of the Hawaiian crow, Corvus hawaiiensis,from past wild to current captive populations
For most avian species, social behaviour is critically important for survival and reproductive success. Many social behaviours in birds are culturally transmitted, and as bird populations decline across the globe, important elements of these behaviours may be lost. The Hawaiian crow or 'alalā, Corvus hawaiiensis, is a socially complex avian species that is currently extinct in the wild. As in other oscine passerines, vocalizations in the 'alalā may be culturally transmitted. We compared the vocal repertoire of three of the last four wild 'alalā pairs from the early 1990s to three current captive pairs on the Island of Hawai'i to determine how acoustic behaviour has been affected by changes in their social and physical...