Mechanisms underlying the loss of migratory behaviour in a long-lived bird

Andrade, Pedro, Franco, Aldina M. A., Acácio, Marta, Afonso, Sandra, Marques, Cristiana I., Moreira, Francisco, Carneiro, Miguel and Catry, Inês (2025) Mechanisms underlying the loss of migratory behaviour in a long-lived bird. Journal of Animal Ecology. ISSN 0021-8790

Full text not available from this repository. (Request a copy)

Abstract

1. Human-induced environmental changes are changing the migration patterns of birds worldwide. Species are adjusting migration timing, shortening and diversifying migratory routes or even transitioning towards residency. While the ultimate causes driving changes in migratory patterns are well established, the underlying mechanisms by which migratory species adapt to environmental change remain unclear. 2. Here, we studied the mechanisms driving the recent and rapid loss of migratory behaviour in Iberian white storks Ciconia ciconia, a long-lived and previously fully migratory species through the African–Eurasian flyway. We combined 25 years of census data, GPS-tracking data from 213 individuals (80 adults and 133 first-year juveniles) tracked up to 7 years and whole-genome sequencing to disentangle whether within- (phenotypic flexibility) or between- (developmental plasticity or microevolution, through selection) individual shifts in migratory behaviour over time explain the observed population-level changes towards residency. 3. Between 1995 and 2020, the proportion of individuals no longer migrating and remaining in Southern Europe year-round increased dramatically, from 18% to 68–83%. We demonstrate that this behavioural shift is likely explained by developmental plasticity. Within first-year birds, 98% crossed the Strait of Gibraltar towards their African wintering grounds, in Morocco or Sub-Saharan Africa. However, the majority shifted towards a non-migratory strategy as they aged—the proportion of migrants decreased to 67% and 33%, in their second and third year of life, respectively. Supporting these findings, only 19% of GPS-tracked adults migrated. We did not find evidence of phenotypic flexibility, as adults were highly consistent in migratory behaviour over multiple years (only 3 individuals changed strategy between years, out of 113 yearly transitions), nor of selection acting on genetic variation, since genomes of adult migrants and residents are essentially undifferentiated and we did not find evidence of selective sweeps in resident birds. 4. Our results suggest that through developmental plasticity, traits that are plastic during specific windows of development become fixed during adulthood. Thus, inter-generational shifts in the frequency of migratory and non-migratory young individuals could drive population changes in migratory behaviour. This can provide a mechanism for long-lived migratory birds to respond to rapid human-driven environmental changes.

Item Type:	Article
Additional Information:	DATA AVAILABILITY STATEMENT: Chromium sequencing data for reference genome assembly and whole-genome re-sequencing data are available in the Sequence Read Archive (www.ncbi.nlm.nih.gov/sra) under BioProject PRJNA713582. FUNDING INFORMATION: This work was financed by the FEDER Funds through the Operational Competitiveness Factors Program—COMPETE and by National Funds through FCT (Fundação para a Ciência e Tecnologia) within the scope of the project Birds on the move ‘POCI-01-0145-FEDER-028176’, and POCI-01-0145-FEDER-006821, with support from the REN Biodiversity Chair and by the Natural Environment Research Council (NERC), via the EnvEast DTP, and NERC and Engineering and Physical Sciences Research Council (EPSRC), via the NEXUSS CDT Training in the Smart and Autonomous Observation of the Environment (NE/R012156/1). Funding for the development of the GPS tracking devices was provided by NERC (NE/K006312), Norwich Research Park Translational Fund, University of East Anglia Innovation Funds and Earth and Life Systems Alliance funds. P.A. was supported by FCT through a research contract in the scope of project PTDC/BIA-EVL/28621/2017 and research contract 2020.01405.CEECIND/CP1601/CT0011. M.A. was supported by NERC, via the NEXUSS CDT (NE/R012156/1). C.I.M. was supported by FCT through a research grant (SFRH/BD/147030/2019) in the scope of the Biodiversity, Genetics, and Evolution (BIODIV) PhD program. M.C. was supported by FCT through POPH-QREN funds from the European Social Fund and Portuguese MCTES (CEECINST/00014/2018/CP1512/CT0002). I.C. and F.M. were supported by FCT (contract numbers 2021.03224.CEECIND and IF/01053/2015, respectively). Work supported by National Funds through FCT in the scope of the project LA/P/0048/2020.
Faculty \ School:	Faculty of Science > School of Environmental Sciences University of East Anglia Research Groups/Centres > Theme - ClimateUEA
UEA Research Groups:	Faculty of Science > Research Centres > Centre for Ecology, Evolution and Conservation Faculty of Science > Research Groups > Environmental Biology
Depositing User:	LivePure Connector
Date Deposited:	27 Mar 2025 10:33
Last Modified:	23 Apr 2025 16:30
URI:	https://ueaeprints.uea.ac.uk/id/eprint/98890
DOI:	10.1101/2024.03.06.583673

Actions (login required)

View Item