Spatial structuring in early life stage fish diversity in the Scotia Sea region of the Southern Ocean

• DOI: 10.1007/s00300-023-03210-z
• Publication Date: 2023-12-16T03:01:42Z
• Authors: Tracey Dornan; Tor Knutsen; Bjørn A. Krafft; Merete Kvalsund; Alejandro Mateos-...; Geraint A. Tarling; Rupert Wienerroither; Simeon L. Hill
• Keywords: Demersal zone; Demersal fish; Bycatch

Abstract The fish community of the Scotia Sea is diverse and plays key roles in Antarctic food webs biogeochemical cycling. However, knowledge spatial structure their early life stages limited, particularly region surrounding South Orkney Islands. Here we examine stage epipelagic using data from a basin-scale survey conducted 2019, which sampled top 200 m water column. 347 19 genera were caught 58 hauls. A third all specimens belonged to genus Notolepis nine most common comprised over 90% specimens. Cluster analysis revealed five distinct groupings, group dominated by pelagic shelf slope ( , Muraenolepis Electrona ) found mainly oceanic waters (depth ≥ 1000 m), species with demersal or benthopelagic adults Chionodraco Chaenocephalus Nototheniops waters. Bottom depth was main environmental determinant structure, separating on-shelf assemblage at Orkneys less species-rich widespread taxa. Our results indicate highest diversities endemic occur on near-shelf areas. Dedicated monitoring recommended understand seasonal differences larval assemblages implications bycatch within krill fishery.