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Initiating and developing social relationships with strangers can provide fitness benefits, but it is an inherently risky process. To mitigate potential risks and develop trust, strangers may ‘test the waters’ by gradually escalating the type of social investment from low-cost to high-cost. Opportunities to capture the moment animals first encounter one another in the wild are rare, and detailed quantitative assessments of when and how animals initiate relationships are limited. We introduced four unfamiliar groups of feral monk parakeets together into a single 22-bird group and observed the sequence of social behaviours that occurred as relationships developed over 22 days. We tested the effect of relationship status (stranger versus familiar) on the probability of dyads following predicted sequences and whether strangers who progressed their relationships maintained higher rates of no-contact proximity compared with dyads that did not. We found that stranger dyads, but not familiar dyads, were more likely to (i) approach each other without contact before making contact and (ii) follow predicted sequences of affiliative behaviours. Strangers that progressed to contact also had higher rates of associations than did birds that never made contact. These findings provide support for ‘Testing the Waters’ during new relationship formation in a socially and cognitively complex species.
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This content will become publicly available on November 1, 2026
The Effect of Familiarity on the Temporal Dynamics of Spatial and Affiliative Associations in Monk Parakeets
To successfully navigate dynamic social environments, animals must manage their relationships by deciding who to interact with, how often, and when. Relationships may develop between familiar group members, but novel relationships can also form as strangers join groups. The process through which relationships form among strangers is not well-known for most species. We used a captive population of monk parakeets (Myiopsitta monachus) with known familiar and stranger relationships to test how novel relationships form among strangers. We established a novel social group by combining 22 parakeets captured from four geographically distinct locations. We quantified how familiar relationships differed from stranger relationships and whether we could detect convergence of the patterning and timing of spatial and affiliative associations across three contexts: general spatial proximity, nearest neighbor identity, and affiliative interactions. We found that familiar networks were consistently more well-connected during the experiment, but relationships did form between former stranger birds across all three behavioral contexts. Spatial proximity associations formed readily for both familiar and stranger birds, while nearest neighbor and affiliative interactions occurred more quickly among familiar dyads, indicating that the rate and patterning of how these relationships were formed differed. We found that the birds consistently preferred familiars across all behavioral contexts with no clear patterns of convergence between familiars and strangers, but the degree of preference depended on the social context. Overall, these findings suggest that parakeets recognize and differentiate between birds they might have encountered previously and that relationships with familiar and stranger conspecifics are not interchangeable.
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- Award ID(s):
- 2239099
- PAR ID:
- 10694201
- Publisher / Repository:
- Animal Behavior and Cognition
- Date Published:
- Journal Name:
- Animal Behavior and Cognition
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 2372-5052
- Page Range / eLocation ID:
- 498 to 520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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