Browse by author
Lookup NU author(s): Dr Chris RedfernORCiD
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
© 2025 The Author(s). IBIS published by John Wiley & Sons Ltd on behalf of British Ornithologists' Union.Many seabird species are in decline and population demographic models are important for revealing the causes and developing conservation strategies. Natal and breeding dispersal are key parameters of such models but can be challenging to estimate and may vary by sex. Along the Northumberland coast, Arctic Terns Sterna paradisaea nest across sites separated by distances up to 32 km. From ringing and recapture of nestling and nesting adult Arctic Terns over two decades, natal philopatry in component sites of this metapopulation was high and recruitment to a colony with managed public access was similar to nearby colonies with no public access. Mean head length of nesting birds recruited to non-natal sites was significantly smaller than those nesting on their natal site. Sexual-size dimorphism was used to estimate the proportions of each sex in capture samples and indicated that males were generally faithful to their natal site but up to nearly one-third of females may have dispersed to non-natal sites. Arctic Terns breed from 2 years of age; head-length data indicated that breeding birds 2–4 years old were mainly female, and suggested that the first-breeding age of males was up to 3 years older. Young breeding birds were caught later in breeding seasons than older birds. Unexpected colony abandonment can confound estimates of natal philopatry and dispersal in metapopulations. These results demonstrate the value of mark–recapture studies and indicate that sex-specific dispersal and breeding-age parameters will be essential components of demographic models.
Author(s): Redfern CPF, Steel D, Morrison PG
Publication type: Article
Publication status: Published
Journal: Ibis
Year: 2025
Pages: epub ahead of print
Online publication date: 27/08/2025
Acceptance date: 07/08/2025
Date deposited: 09/09/2025
ISSN (print): 0019-1019
ISSN (electronic): 1474-919X
Publisher: John Wiley and Sons Inc
URL: https://doi.org/10.1111/ibi.13444
DOI: 10.1111/ibi.13444
Data Access Statement: Raw ringing and biometric data are held on the British Trust for Ornithology (BTO) databases and may be obtained on application to the BTO. Alternatively, summarized and processed data used for the analyses reported here can be obtained from author C.P.F.R or the Zenodo database https://doi. org/10.5281/zenodo.16918052
Altmetrics provided by Altmetric
