Street smart: faster approach towards litter in urban areas by highly neophobic corvids and less fearful birds
This is the author accepted manuscript. The final version is available from Elsevier Masson via the DOI in this record.
The extent to which animals respond fearfully to novel stimuli may critically influence their ability to survive alongside humans. However, it is unclear whether the fear of novel objects, object neophobia, consistently varies in response to human disturbance. Where variation has been documented, it is unclear whether this variation is due to a change in fear towards specific novel stimuli, or whether it is symptomatic of a general change in fear behaviour. We measured levels of object neophobia in free-flying birds across urban and rural habitats, comparing corvids, a family known for being behaviourally flexible and innovative, with other urban-adapting bird species. Neophobic responses were measured in the presence of different types of objects that varied in their novelty, and were compared to behaviour during a baited control. Corvids were more neophobic than noncorvid species towards all object types, but their hesitancy abated after conspecifics approached in experimental conditions in which objects resembled items they may have experienced previously. Both sets of species were faster to approach objects made from human litter in urban than rural areas, potentially reflecting a category-specific reduction in fear based on experience. These results highlight species similarities in behavioural responses to human-dominated environments despite large differences in baseline neophobia.
We owe a big thank you to Christopher Smith for his help in coding videos, and to Guill McIvor for his tireless ringing efforts and field support. We are very grateful to Paul Gluyas and the entire staff at Pencoose farm, to Stithians Parish Council and to David Fisher, Julian Evans and Shona Jack for allowing us to put up feeding tables on their land and in their gardens. Finally, we thank Sinéad English for advice on statistics and Laura Kelly for help with the spectral analyses. A.G. received generous support from the Gates-Cambridge Trust. A.T. was supported by a BBSRC David Phillips Fellowship (BB/H021817/1) and a grant from the British Ecological Society2769/3464.
This is an open access article.
Vol. 117, pp. 123 - 133