5. Acknowledgements
EHS was supported by a NERC GW4+ Doctoral Training Partnership studentship from the Natural Environment Research Council (grant NE/L002434/1) and is thankful for the support and additional funding from CASE partner the Royal Society for the Protection of Birds (grant 210-x-1656). The authors thank the Welsh Ornithological Society for providing additional funding. The authors would like to thank Will Kirby and all the members of the Hawfinch ringing group for assistance with sample collection, and to Angela Marchbank and Trudy Workman of the Cardiff University Genomics Hub for assistance with high-throughput sequencing. Thanks also to Lorna Drake and Sarah Davies for training and advice in bioinformatics.