Conserving avian vocal culture

Abstract

Over 40% of bird species learn their vocalizations from conspecifics. Avian vocalizations therefore represent one of the most pervasive and quantifiable examples of culturally acquired behaviour that evolves and is maintained within populations through conformity and selection. We review research exploring the loss of vocal culture in wild birds and synthesize how this loss may occur through three processes, defined as erosion/fragmentation, divergence and convergence. We discuss the potential to conserve avian vocal cultures in the wild and in captivity, using the regent honeyeater Anthochaera phrygia as a case study. Given the current rates of global biodiversity decline, we predict that more examples of avian vocal culture loss will emerge in the future. There is a need, therefore, for a better understanding of (i) how pervasive loss of vocal culture is in birds; (ii) what factors predispose birds to loss of vocal culture; (iii) the fitness costs of loss of vocal culture, including the population size or density range within which fitness costs may be greatest; and (iv) how vocal cultures can best be conserved or restored. This knowledge could then inform management actions such that the diversity of the world’s birds and their vocalizations can be maintained for generations to come