The coronavirus disease 2019 (COVID-19) pandemic and respective shutdowns dramatically altered human activities, potentially changing human pressures on urban-dwelling animals. Here, we use such COVID-19-induced variation in human presence to evaluate, across multiple temporal scales, how urban birds from five countries changed their tolerance towards humans, measured as escape distance. We collected 6369 escape responses for 147 species and found that human numbers in parks at a given hour, day, week or year (before and during shutdowns) had a little effect on birds' escape distances. All effects centered around zero, except for the actual human numbers during escape trial (hourly scale) that correlated negatively, albeit weakly, with escape distance. The results were similar across countries and most species. Our results highlight the resilience of birds to changes in human numbers on multiple temporal scales, the complexities of linking animal fear responses to human behavior, and the challenge of quantifying both simultaneously in situ.

Arctic Centre University of Lapland PO Box 122 96101 Rovaniemi Finland

Deakin Marine School of Life and Environmental Sciences Deakin University Burwood Campus 221 Burwood Highway VIC 3125 Burwood Melbourne Australia

Department of Ecology and Evolutionary Biology University of California 621 Young Drive South Los Angeles CA 90095 USA

Department of Ecology Institute of Biology University of Veterinary Medicine Budapest Rottenbiller u 50 1077 Budapest Hungary

Department of Plant Pathology Institute of Plant Protection Hungarian University of Agriculture and Life Sciences Ménesi út 44 1118 Budapest Hungary

Department of Zoology Faculty of Science Charles University Viničná 7 12844 Prague Czech Republic

Ecologie Systématique Evolution Université Paris Sud CNRS AgroParisTech Université Paris Saclay 91405 Orsay Cedex Paris France

Faculty of Environmental Sciences Czech University of Life Sciences Prague Kamýcká 129 16500 Prague Czechia

Institute for Advanced Study Technical University of Munich 85748 Garching Germany

Institute of Biological Sciences University of Zielona Góra Prof Z Szafrana St 1 65516 Zielona Góra Poland

Institute of Vertebrate Biology Czech Academy of Sciences Květná 8 60365 Brno Czech Republic

Institute of Zoology Poznań University of Life Sciences Wojska Polskiego 71C 60625 Poznań Poland

Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering College of Life Sciences Beijing Normal University 100875 Beijing China

TUM School of Life Sciences Ecoclimatology Technical University of Munich 85354 Freising Germany

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Urban birds' tolerance towards humans was largely unaffected by COVID-19 shutdown-induced variation in human presence