Why do birds incorporate anthropogenic material into their nests?

Many bird species have been reported to incorporate anthropogenic materials - such as cigarette butts, baler twine and pieces of plastic foil - into their nests and in this presentation, we will outline the causes and consequences of this emerging novel behaviour. We will show the results of a phylogenetically informed comparative analysis that will examine interspecific variation in the use of anthropogenic materials among species and the traits underlying its usage. We will also describe the diversity of anthropogenic materials that are found in birds’ nests, and discuss the proximate consequences (i.e. ecological and physiological) of the far greater persistence of anthropogenic materials - such as plastic - in the environment for nest-building birds and their offspring. Finally, we will provide a conceptual framework for this topic and highlight those areas where further attention is most urgently warranted in this burgeoning research field.