Flight initiation distance is repeatable and geographically flexible in greylag geese (Anser anser)

The decision to flee from an approaching threat represents a trade-off between the costs and benefits of flight. In research to date, particular interest has been given to the effects of urbanisation on predator escape behaviour. However, these differences are most often studied at the population rather than individual level, which makes it difficult to disentangle whether site-specific differences in predator avoidance are due to behavioural plasticity or non-random distribution of behavioural phenotypes. In this study, we measured flight initiation distances—a widely used proxy for fearfulness or boldness—in a free-roaming, human-habituated, and colourbanded population of greylag geese (Anser anser). First, we tested whether individuals flexibly adjusted their flight initiation distance based on environmental context, by approaching the same individuals at two sites with different levels of human presence. Second, we examined whether flock members show consistent differences in their ..., , , # Flight initiation distance is repeatable and geographically flexible in greylag geese (Anser anser)

[https://doi.org/10.5061/dryad.pvmcvdnw5](https://doi.org/10.5061/dryad.pvmcvdnw5)

## Description of the data and file structure

Full details for this dataset are given in Katsis et al., (2024, *Journal of Avian Biology*).

#### Study sites and species

This study was conducted in a free-roaming population of greylag geese in Grünau im Almtal, Upper Austria. All members of the flock are individually identifiable; almost all geese are marked with a unique combination of aluminum and colored leg bands and any unbanded individuals can be distinguished from their facial markings. Some flock members (n = 11) were hand-raised by a human foster parent until fledging, as part of an ongoing long-term research program. We collected data over two testing periods outside the greylag goose breeding season and approximately 13 months apart: 8–14 September 2022 and 10–29 October 2023. During the fi...