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Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Flock size does not influence escape decisions of urban lawn-foraging birds

Jin-Ming Zhao https://orcid.org/0000-0003-2305-7643 A * , Xiang-Rong Song A B , Xiao-Yu Yang A , Yue Xie A and Xiao-Nong Yang C
+ Author Affiliations
- Author Affiliations

A School of Life Science, Huaibei Normal University, No. 100, Dongshan Road, Huaibei 235000, People’s Republic of China.

B School of Resources and Environmental Engineering, Anhui University, No.111, Jiulong Road, Hefei 230601, People’s Republic of China.

C Chengdu Bird Watching Society, No. 13, Yulinnan Road, Chengdu 610041, People’s Republic of China.

* Correspondence to: zhaojm2022@163.com

Handling Editor: Aaron Wirsing

Wildlife Research 51, WR23042 https://doi.org/10.1071/WR23042
Submitted: 2 April 2023  Accepted: 4 November 2024  Published: 21 November 2024

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context

Predator avoidance is considered a key evolutionary driver shaping aggregation behavior. An overlooked aspect in the study of predator avoidance is whether individuals can make better escape decisions (i.e. gain greater benefits) when in larger groups. Escape decisions encompass when to flee (FID: the distance at which an animal moves away from approaching threats), how far to flee (distance fled, DF), flight direction (FD) and whether to seek refuge.

Aim

This study evaluates the influence of flock size on the FID, DF and FD in urban birds.

Methods

We studied a series of escape behaviors of eight urban lawn-foraging bird species in Huaibei city, China, approached by one, two or three persons representing varying levels of predation risk.

Key results

We found that flock size had a limited effect on birds’ escape decisions, including FID, DF, FD and refuge-seeking behavior, with some species-specific effects. Predation risk (number of approachers) also had a subtle influence on birds’ escape decisions.

Conclusions

Urban birds generally exhibit consistent escape behavior regardless of flock size or predation risk.

Implications

Urban birds might maintain a minimum antipredator response to approaching humans due to their extensive habituation to human occurrence. Future research should examine how urban birds’ responses to humans compare with their reactions to natural predators, and investigate the varying impacts of urbanization on these behaviors.

Keywords: antipredator behavior, distance fled, flight direction, flight initiation distance, flock size, group living, habituation, predation risk, urban birds.

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