Distribution and structure of deep-sea demersal fish assemblages across the central and western Pacific Ocean using data from undersea imagery

Deep-sea demersal fish assemblages in the central and western Pacific Ocean exhibit significant regional and depth-related variations, with diversity decreasing as depth increases. The study, leveraging data from 227 underwater vehicle dives, identified 89 families and 175 genera of fishes across four Marine National Monuments, revealing that these regions are not replicates but complementary components of the regional fauna. Depth and region were the primary drivers of assemblage structure, followed by environmental factors such as seafloor particulate organic carbon flux, dissolved oxygen concentrations, and salinity. The Line Islands and Tokelau Ridge showed the highest fish abundance at shallower depths (250-1000 m) due to higher food supply proxies. Taxon accumulation curves suggested that genus-level diversity had not been fully captured in most regions except at the deepest zones. This research highlights the importance of considering both regional and depth-related factors when assessing deep-sea fish biodiversity, with implications for conservation efforts in these remote marine areas.

Selig, G. M., Drazen, J. C., Auster, P. J., Mundy, B. C., & Kelley, C. D. (2023). Distribution and structure of deep-sea demersal fish assemblages across the central and western Pacific Ocean using data from undersea imagery. Frontiers in Marine Science, 10. https://doi.org/10.3389/fmars.2023.1219368