Deep-sea biodiversity at the extremes of the Salas y Gómez and Nazca ridges with implications for conservation

Conclusion Our study supports mounting evidence that the Salas y Go´mez and Nazca ridges have high biodiversity and unique ecological characteristics. The rich deep-water communities that inhabit this region provide a lifeline for marine biodiversity in the Pacific, and sustain produc- tivity with surrounding waters, representing a sentinel site for ecosystem connectivity across large ocean corridors. However, the consequences of continued or increased stressors on this marine region are severe. While our study did not focus on characterizing stressors, previous studies have concluded that this region is threatened by plastic pollution, climate change, industrial fishing, and seabed mining [53]. With informed, effective, and strong conservation measures, we can ensure the Salas y Go´mez and Nazca ridges remain a globally unique biodi- versity hotspot. Supporting information S1 Table. Summary statistics for environmental variables between regions deep-sea camera deployments along the Salas y Go´mez and Nazca ridges. (DOCX) S2 Table. Invertebrate taxa observed on deep-sea camera deployments along the Salas y Go´mez and Nazca ridges. VME = vulnerable marine ecosystem taxa. Msp = morpho-species. Freq. Des = frequency of occurrence Desventuradas (n = 27). Freq. Rn/SyG = frequency of occurrence Rapa Nui/Salas y Go´mez (n = 20). (DOCX) S3 Table. Vertebrate taxa observed on deep-sea camera deployments along the Salas y Go´mez and Nazca ridges. Msp = morpho-species. � = endemic species. (DOCX) Acknowledgments

We wish to thank Eric Berkenpass for his tireless work on camera deployments. We thank the taxonomic experts who provided input on fauna identifications, including Dave Ebert, Mary Wicksten, Chris Kelley, Jan M. Tapia-Guerra, Bruce Mundy, Hiroyuki Motomura, Brian Greene, and Ken Sulak. Author Contributions Conceptualization: Alan M. Friedlander, Daniel Wagner. Data curation: Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton. Formal analysis: Alan M. Friedlander, Whitney Goodell, Erin E. Easton. Funding acquisition: Alan M. Friedlander, Daniel Wagner. Investigation: Alan M. Friedlander, Jonatha Giddens, Erin E. Easton, Daniel Wagner. Methodology: Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton. Project administration: Alan M. Friedlander, Daniel Wagner. Resources: Alan M. Friedlander, Whitney Goodell, Erin E. Easton, Daniel Wagner. Software: Alan M. Friedlander, Whitney Goodell. Supervision: Alan M. Friedlander, Daniel Wagner. PLOS ONE Deep-sea biodiversity along the Salas y Go´ mez and Nazca ridges PLOS ONE | https://doi.org/10.1371/journal.pone.0253213 June 30, 2021 21 / 27