Contrasting life-history characteristics between riverine and lacustrine anadromous Arctic char (Salvelinus alpinus) in the western Canadian Arctic

Freshwater habitat characteristics are known to affect life-history traits of migratory salmonids. Although the life cycle of the anadromous form of Arctic char (Salvelinus alpinus) is typically associated with lakes, there is a small number of anadromous populations in North America that spawn, rear, and overwinter exclusively in rivers. The life-history traits of these relatively understudied populations and how they differ from lacustrine Arctic char are poorly documented. We characterized life-history tradeoffs expressed by anadromous Arctic char originating from a riverine (Hornaday River) and a relatively nearby lacustrine system (Tatik Lake of the Kuujjua River) in the western Canadian Arctic using a 10 year dataset. The riverine population attained smaller average size (600 mm vs. 628 mm, fork length) and age (7.7 vs. 10.6 years), had a lower longevity (14 vs. 26 years), expressed a 44% higher growth rate resulting in larger size-at-age prior to reaching modelled length asymptote (700 vs. 754 mm), had a younger modal age-at-maturity (~6-7 vs. ~11-13 years) and mean age-at-first migration (4.1 vs. 6.4 years), and a higher natural mortality rate (0.31 vs. 0.21 per year). Our results broaden knowledge on the spectrum of life-history strategies exhibited by anadromous Arctic char and underscore how freshwater habitat influence vital rates and life-history tradeoffs, which have implications for conservation and sustainable harvest of salmonids. Supplementary Material File (riverine-lacustrine_arctic_char_2025.06.06.docx) - Download - 5.43 MB Information & Authors Information Version history Peer review timeline Published Ecology and Evolution Version of Record19 Dec 2025Published Copyright This work is licensed under a Non Exclusive No Reuse License. Collection

Authors Metrics & Citations Metrics Article Usage 294views 219downloads Citations Download citation Colin Gallagher, Xinhua Zhu, Ellen Lea, et al. Contrasting life-history characteristics between riverine and lacustrine anadromous Arctic char (Salvelinus alpinus) in the western Canadian Arctic. Authorea. 09 June 2025. DOI: https://doi.org/10.22541/au.174946164.46816603/v1 DOI: https://doi.org/10.22541/au.174946164.46816603/v1 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. For more information or tips please see 'Downloading to a citation manager' in the Help menu.