AUTHOR=Eccles Georgina R. , Bethell Emily J. , Greggor Alison L. , Mettke-Hofmann Claudia 

TITLE=Individual Variation in Dietary Wariness Is Predicted by Head Color in a Specialist Feeder, the Gouldian Finch

JOURNAL=Frontiers in Ecology and Evolution

VOLUME=Volume 9 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/ecology-and-evolution/articles/10.3389/fevo.2021.772812

DOI=10.3389/fevo.2021.772812

ISSN=2296-701X

ABSTRACT=Shifts in resource availability due to environmental change are increasingly confronting animals with unfamiliar food types. Species that can rapidly accept new food types may be better adapted to handle ecological change. Intuitively, dietary generalists are expected to forage on new food types when available resources change, while dietary specialists would be more averse to adopting novel food. However, most studies investigating changes in dietary breadth focus on generalist species and do not delve into potential individual predictors of dietary wariness and the social factors modulating these responses. We investigated dietary wariness in the Gouldian finch, a dietary specialist that is therefore expected to avoid novel food. It occurs in two main head colors, which signal personality in other contexts. We measured their initial neophobic responses (approach attempt before first feed and latency to first feed) and willingness to incorporate novel food into their diet (frequency of feeding on novel food after first feed). Birds were tested in same-sex pairs with a partner of the same and a different head color across two experiments. Familiar and novel food (familiar food dyed) were presented together for 3 hours each day across five days. Gouldian finches fed on the familiar food first, and showed more approach attempts before feeding on novel food than familiar food, demonstrating food neophobia. Neophobia responses were partly repeatable, and approach frequencies differed between morphs. Partner head color affected responses. Individuals consistently differed in their rate of incorporation of novel food, with clear differences between head colors; Red-headed birds increased their feeding visits to novel food across experimentation equalling their familiar food intake by the final day of experimentation, while black-headed birds continually favored familiar food. Results suggest consistent among individual differences in response to novel food with red-headed birds being adventurous consumers and black-headed birds dietary conservatives. The differences in food acceptance aligned with responses to novel environments on the individual level (found in an earlier study) providing individuals with an adaptive combination of novelty responses across contexts in line with potential differences in movement patterns. Taken together, these novelty responses could aid in population persistence.