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Abstract Animals often avoid novel objects, a behavior known as neophobia. We examined behavioral responses of captive European starlings to novel objects placed at their food dishes. Exposure occurred concurrently to food reintroduction following overnight fasting. Behavior was analyzed for 10 min via video recording. We expected an increase in avoidance behavior compared with trials in which food was reintroduced without a novel object. Seven of 10 novel objects increased latency to approach the dish. In contrast to our expectations, neither prior restraint nor exogenous corticosterone changed the neophobic response to novel objects. While exposure to a novel object increased approach latency, there was no additional effect of restraining animals in a cloth bag for 15 min before food reintroduction. Furthermore, the subcutaneous injection of corticosterone did not affect approach latency by itself, nor did it affect the response to a novel object. Finally, we expected repeated exposure to the same object to extinguishing the neophobic response, and that restraint stress would prevent habituation. Our results show that European starlings habituate rapidly to exposure to a novel object, as approach latency returned to baseline within three repeated exposures to the same object. When the repeated presentation of the object was combined with prior restraint, however, the latency to approach never returned to baseline. These results reveal that neophobia in starlings is object‐specific and that, while neither acute stress nor corticosterone directly affects the behavioral response to a novel object, acute stress appears to have a permissive effect on neophobia by inhibiting habituation.
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Captive house sparrows ( Passer domesticus ) show little evidence of seasonality of neophobia responses
Abstract Neophobia is a behavior characterized by a reluctance to approach novel objects. We measured neophobia in captive wild house sparrows (Passer domesticus) by comparing the time it took for hungry birds to approach their normal food dish compared to one that had been modified with a novel object. We tested the behavior of animals captured at different times of year to test for seasonal variation in neophobia. One group of birds tested in July approached their food dishes much more quickly than all other birds (a matter of seconds rather than minutes whether or not there was a novel object), a response that was not repeated in a subsequent July. When this possible outlier group was removed from the analysis, approach times to novel objects were not affected by season. However, animals captured and tested in October had a stronger motivation to feed (i.e., they approached unmodified food dishes faster) than birds captured at other times of the year. If we define “neophobia” as an increase in latency to approach a novel versus an unmodified food dish, then there is little evidence for underlying seasonal variation in risk assessment, although a general motivation to feed does show a seasonal pattern.
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- Award ID(s):
- 1655269
- PAR ID:
- 10147235
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Experimental Zoology Part A: Ecological and Integrative Physiology
- Volume:
- 333
- Issue:
- 7
- ISSN:
- 2471-5638
- Page Range / eLocation ID:
- p. 478-482
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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