Taxonomy and phylogeography of the Irish Arctic char ( Salvelinus alpinus ). Report No. 444

A comprehensive genetic analysis of Arctic char (Salvelinus alpinus) populations in Irish loughs was undertaken to address several aspects relevant to conservation and management. First, the study aimed to clarify the taxonomic status of this species, investigating whether there is scientific evidence supporting the existence of multiple char species in Ireland. Second, it sought to uncover the phylogeographical history and population structure of contemporary Arctic char populations in Ireland. Third, it assessed the impact of scientific communication on conservation decisions made by policymakers, using an environmental economics analytical framework. Finally, the study aimed to provide insights into the development of effective conservation measures for Arctic char in Ireland, using the genetic data generated in conjunction with other available information. The study involved sampling Arctic char from 37 loughs in Ireland, representing 82% of the loughs where the species has been recorded as naturally present. Archived samples were also available from 18 additional loughs where Arctic char is now thought to be extinct. Limited samples from Scotland (UK), England (UK) and Sweden were included in the dataset for comparison. Historical specimens, collected during the late 1800s and early 1900s, were sourced from the Natural History Museum in London and the National Museum of Ireland. These included holotypes and syntypes associated with species previously described in Ireland by Günther (1862, 1863) and Regan (1908, 1911). In total, over 3200 Arctic char specimens were analysed during the study. The analysis involved the examination of genetic data from both nuclear and mitochondrial DNA (mtDNA), in addition to morphometric data. Single nucleotide polymorphism (SNP) markers were developed for both nuclear DNA and mtDNA, based on a sample set of 288 individuals representing 29 Irish Arctic char loughs, along with specimens from England and Scotland for reference. Nuclear SNP markers were employed to screen the ...