Multi-year residency and movement patterns of Arctic skate Amblyraja hyperborea, a bycatch species, across an Arctic community fishing ground

Understanding the residency and movement patterns of at-risk species is critical for effective conservation and management. Due to declining sea ice, Arctic skate Amblyraja hyperborea could be a potentially vulnerable bycatch species in expanding Arctic fisheries targeting Greenland halibut Reinhardtius hippoglossoides . Multi-year acoustic telemetry (2011-2012 and 2014-2016) at depths of 400-1200 m in Cumberland Sound (Nunavut, Canada) revealed that most Arctic skates remained resident or displayed fidelity (29 individuals, 69%) to the location where they were released. Dispersal was generally limited (<20 km; n = 31; 74% of detected individuals), although 11 skates (26%) exhibited higher mobility which could exceed 100 km. Resident skates were present across an annual cycle, experiencing varying bottom water temperatures (0.5-2.6°C), dissolved oxygen levels (2.63-3.99 μmol l -1 ), and sea ice concentrations (0-100%). These findings suggest that Arctic skate distribution in Cumberland Sound is influenced more by sedentary behaviour than by hydrodynamic conditions, with regional residency maintained over multiple years. Concurrent tracking of Greenland halibut revealed contrasting movement patterns: while Arctic skates exhibited residency, Greenland halibut displayed seasonal mobility. Sedentary behaviour increases the vulnerability of Arctic skates to bycatch, as Greenland halibut migrations overlap with resident Arctic skates across Cumberland Sound. Consequently, growth of Greenland halibut fisheries will heighten Arctic skate bycatch risk; thus, local extirpation risks are a concern, requiring fisheries to consider (1) bycatch monitoring strategies, (2) improved handling practices, and (3) an assessment of depth-based mortality risk following capture and release.