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

Over 73% of the Salas y Go´mez and Nazca ridges are in ABNJ without protections from fishing. Globally, ABNJ account for only 4.2% of annual marine capture fisheries production, with most species destined for upscale markets in developed, food-secure countries, such as Japan, the European Union, and the United States, suggesting high seas fisheries play a negligi- ble role in ensuring global food security [96]. Deep-sea and high seas fishing often produces net economic benefits only due to subsidies as most of the world’s largest fishing fleets would be unprofitable without subsidies and low labor costs [97]. Closing the high seas would be catch-neutral, while reducing inequality in the distribution of fisheries benefits among the world’s maritime countries by 50% [98]. Climate change It is predicted that in the next 20–40 years, the seafloor of this region will experience increases in temperature, acidification, decreases in dissolved oxygen, and declining export of particu- late organic carbon [24, 99]. Portions of this region are already extremely nutrient [100] and oxygen-poor [51], so the global threat of climate change is especially heightened in this region and in need of management intervention to protect ecosystem structure and function. The numerous endemic species in this region are at high risk of extinction from climate change, as they have limited ranges, small thermal safety margins, and unique habitat and environmental requirements [29, 101, 102]. In addition, primary productivity and fisheries production are

projected to decline throughout the region over the next several decades due to climate change [103], and these changes will impact the entire ecosystem and require a precautionary approach to management of human use. Conservation opportunities Numerous previous studies have noted the exceptional natural and cultural significance of the Salas y Go´mez and Nazca ridges (reviewed in [53]). In 2014, at the 12th Meeting of the Confer- ence of the Parties [104], the Salas y Go´mez and Nazca ridges were recognized as an ecolog- ically or biologically significant marine area (EBSA). The eastern part of the Nazca Ridge is part of the most productive marine ecosystem in the world and is one of the region’s most unique underwater habitats [29, 105]. Seamounts on the Salas y Go´mez and Nazca ridges host a high abundance and diversity of unique organisms and provide important habitat and migration corridors for protected megafauna such as blue whales, leatherback turtles, and sharks; important fisheries species such as swordfish (Xiphias gladius) and Chilean jack mack- erel (Trachurus murphyi); and a diversity of other ecologically important species such as habi- tat-forming deep and shallow-water corals [27, 41, 106–110]. The results of this study provide additional evidence that the Salas y Go´mez and Nazca ridges are of high natural significance and conservation value. Our surveys documented numerous VME and endemic taxa. In addi- tion, some of the endemic taxa were documented on both ends of the Salas y Go´mez Ridge,

supporting previous conclusions that the ridges are important for connectivity as they provide migration corridors and ecological stepping stones for many species [104]. Chile has already protected the portions of the Salas y Go´mez and Nazca ridges that fall within its jurisdictions through various MPAs, including the Rapa Nui Multiple-Use Coastal Marine Protected Area, the Motu Motiro Hiva Marine Park, and the Nazca-Desventuradas Marine Park. While these conservation efforts represent important conservation advances for the region, collectively they only cover 23.8% of the area recognized as an EBSA. Although the portion of the Nazca Ridge that lies within Peru’s national waters has been proposed for increased protections [111], it remains unprotected, highlighting an immediate opportunity for Peru to expand its ocean conservation efforts. To date, Peru has protected only a small 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 19 / 27

fraction of its national waters (< 0.5%) and fallen short of achieving its Aichi Biodiversity Tar- get 11 commitment of protecting 10% of its national waters by 2020. While the recent efforts by Chile and Peru to establish or propose MPAs in the national waters of this region provide important advances, these efforts could be undermined if sur- rounding ecosystems in ABNJ cannot be properly conserved [53]. Over 73% of the ridges fall outside national jurisdictions, where they are unprotected and under threat from overfishing, climate change, plastic pollution, and potential seabed mining. This region has been recog- nized as one of the most important to protect on the high seas globally [27, 112–117]. While the surveys of our study all occurred within Chilean waters of the region, it is highly likely that high seas waters between our study subregions also provide critical habitats and ecological stepping stones for many of the species documented during our surveys. For example, seafloor topography data indicates that there are many seamounts in ABNJ of this region [21], which are well known to provide highly suitable habitats for many of the demersal fish, coral, and sponge taxa recorded in our surveys [69]. Furthermore, recently developed habitat suitability models, indicate that highly suitable habitat for VME taxa is widespread in ABNJ of the Salas y Go´mez and Nazca ridges [118]. Most large-scale features (e.g., seamounts, guyots, ridges, and escarpments) in this region provide suitable habitats for deep-water corals and sponges and all

our survey sites with VME taxa present (n = 20) were in areas of high habitat suitability based on these distribution models. Given the importance of VME taxa in deep-sea ecosystem func- tioning and their slow recovery rates from disturbance, these features should be proactively protected from bottom fishing and seabed mining. Caveats The deep ocean presents many challenges in exploration and assessment given the extreme environmental conditions, remote locations, and paucity of existing data on which to base tar- geted studies [1]. For example, determining habitat type a priori was not possible, resulting in an unbalanced sampling design in our study. Expanded development and accessibility of sea- floor mapping datasets would allow for more informed sampling design and enable more bal- anced representation of different habitat types [119]. Our study is based on opportunistic sampling to provide baseline observations at two remote and underexplored locations. Like all baited-camera methods, our deep-sea camera system is specialized to measure the relative abundance of mobile megafauna that are attracted to bait [61, 120, 121]. However, species’ absences may be less reliably measured by opportunis- tic point video surveys [122]. Further, our deep-sea camera system is designed to optimize the survey field of view and the ability to identify distinguishing characteristics of mobile taxa (e.g., pectoral and anal fins and head characteristics) [61]. However, without physical sam- pling, species-level identifications can be difficult or impossible to determine from video

alone. For example, in the Desventuradas, a new species of Squalidae may have been present, but a physical specimen would be required for confirmation. In most cases in our study, taxo- nomic resolution was achieved to the family level for fishes and order level for invertebrates, which was sufficient for statistical comparisons of assemblage-level differences among locations. Moreover, for baited camera methods, small sessile fauna (e.g., meiofanua, infauna) in the background of a frame can be difficult to confidently identify, therefore this method typically focuses on assessments of mobile megafauna [61, 120, 123]. However, our study recorded numerous VME taxa, therefore we included sessile fauna in our analyses of invertebrate assem- blages as these taxa indicate areas that are of high conservation value. 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 20 / 27

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

Validation: Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton, Daniel Wagner. Visualization: Alan M. Friedlander, Whitney Goodell. Writing – original draft: Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Daniel Wagner. Writing – review & editing: Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton, Daniel Wagner. References 1. Levin LA, Bett BJ, Gates AR, Heimbach P, Howe BM, Janssen F, et al. Global observing needs in the deep ocean. Frontiers in Marine Science. 2019; 6: 241. 2. Ramirez-Llodra E, Brandt A, Danovaro R, De Mol B, Escobar E, German CR, et al. Deep, diverse and definitely different: unique attributes of the world’s largest ecosystem. Biogeosciences. 2010; 7(9): 2851–2899. 3. Howell KL, Hila´ rio A, Allcock AL, Bailey DM, Baker M, Clark MR, et al. A Blueprint for an Inclusive, Global Deep-Sea Ocean Decade Field Program. Frontiers in Marine Science. 2020; 7: 999. 4. McClain CR, Schlacher TA. On some hypotheses of diversity of animal life at great depths on the sea floor. Marine Ecology. 2015; 36(4): 849–872. 5. Rex MA, Etter RJ, Morris JS, Crouse J, McClain CR, Johnson NA, et al. Global bathymetric patterns of standing stock and body size in the deep-sea benthos. Marine Ecology Progress Series. 2006; 317: 1–8. 6. Stuart CT, Arbizu PM, Smith CR, Molodtsova T, Brandt A, Etter RJ, et al. CeDAMar global database of abyssal biological sampling. Aquatic Biology. 2008; 4(2): 143–145. 7. Wei CL, Rowe GT, Hubbard GF, Scheltema AH, Wilson GD, Petrescu I, et al. Bathymetric zonation of

deep-sea macrofauna in relation to export of surface phytoplankton production. Marine Ecology Prog- ress Series. 2010; 399: 1–4. 8. Wei CL, Rowe GT, Escobar-Briones E, Boetius A, Soltwedel T, Caley MJ, et al. Global patterns and predictions of seafloor biomass using random forests. PloS ONE. 2010; 5(12): e15323. https://doi.org/ 10.1371/journal.pone.0015323 PMID: 21209928 9. McClain CR, Stegen JC, Hurlbert AH. Dispersal, niche dynamics, and oceanic patterns in beta-diver- sity in deep-sea bivalves. Proceedings of the Royal Society B. 2012; 279: 1933–2002. 10. Jones DO, Yool A, Wei CL, Henson SA, Ruhl HA, Watson RA, et al. Global reductions in seafloor bio- mass in response to climate change. Global Change Biology. 2014; 20(6): 1861–1872. https://doi.org/ 10.1111/gcb.12480 PMID: 24382828 11. Glover AG, Wiklund H, Chen C, Dahlgren TG. Point of View: Managing a sustainable deep-sea ‘blue economy’requires knowledge of what actually lives there. ELife. 2018; 7: e41319. https://doi.org/10. 7554/eLife.41319 PMID: 30479272 12. Kennedy BR, Cantwell K, Malik M, Kelley C, Potter J, Elliott K, et al. The unknown and the unexplored: insights into the pacific deep-sea following NOAA CAPSTONE expeditions. Frontiers in Marine Sci- ence. 2019; 6: 480. 13. Howell KL, Piechaud N, Downie AL, Kenny A. The distribution of deep-sea sponge aggregations in the North Atlantic and implications for their effective spatial management. Deep Sea Research Part I: Oceanographic Research Papers. 2016; 115: 309–320.

18. Grassle JF, Maciolek NJ. Deep-sea species richness: regional and local diversity estimates from quantitative bottom samples. The American Naturalist. 1992; 139(2): 313–341. 19. Mora C, Tittensor DP, Adl S, Simpson AG, Worm B. How many species are there on Earth and in the ocean? PLoS Biology. 2011; 9(8): e1001127. https://doi.org/10.1371/journal.pbio.1001127 PMID: 21886479 20. Ramirez-Llodra E, Tyler PA, Baker MC, Bergstad OA, Clark MR, Escobar E, et al. Man and the last great wilderness: human impact on the deep sea. PLoS ONE. 2011; 6(8): e22588. https://doi.org/10. 1371/journal.pone.0022588 PMID: 21829635 21. Harris PT, Macmillan-Lawler M, Rupp J, Baker EK. Geomorphology of the oceans. Marine Geology. 2014; 352: 4–24. 22. Levin LA, Le Bris N. The deep ocean under climate change. Science. 2015; 350(6262): 766–768. https://doi.org/10.1126/science.aad0126 PMID: 26564845 23. Halpern BS, Frazier M, Potapenko J, Casey KS, Koenig K, Longo C, et al. Spatial and temporal changes in cumulative human impacts on the world’s ocean. Nature Communications. 2015; 6(1): 1– 7. https://doi.org/10.1038/ncomms8615 PMID: 26172980 24. Levin LA, Wei CL, Dunn DC, Amon DJ, Ashford OS, Cheung WW, et al. Climate Change Consider- ations are Fundamental to Management of Deep-Sea Resource Extraction. Global Change Biology. 2020; 26(9): 4664–4678. https://doi.org/10.1111/gcb.15223 PMID: 32531093 25. Rogers AD. The biology of Lophelia pertusa (Linnaeus 1758) and other deep-water reef-rorming corals and impacts from human activities. International Review of Hydrobiology. 1999; 84(4): 315–406.

26. Freiwald A, Fossa JH, Grehan A, Koslow T, Roberts JM. Cold-water coral reefs: out of sight-no longer out of mind. Cambridge, UK: UNEP-WCMC; 2004. 27. Wagner D, Friedlander AM, Pyle RL, Brooks CM, Gjerde KM, Wilhelm TA. Coral reefs of the high seas: hidden biodiversity hotspots in need of protection. Frontiers in Marine Science. 2020; 7: 776. 28. Kane C, Kosaki RK, Wagner D. High levels of mesophotic reef fish endemism in the Northwestern Hawaiian Islands. Bulletin of Marine Science. 2014; 90(2): 693–703. 29. Friedlander AM, Ballesteros E, Caselle JE, Gaymer CF, Palma AT, Petit I, et al. Marine biodiversity in Juan Ferna´ ndez and Desventuradas Islands, Chile: global endemism hotspots. PLoS ONE. 2016; 11 (1): e0145059. https://doi.org/10.1371/journal.pone.0145059 PMID: 26734732 30. Worm B, Lotze HK, Myers RA. Predator diversity hotspots in the blue ocean. Proceedings of the National Academy of Sciences. 2003; 100(17): 9884–9888. https://doi.org/10.1073/pnas.1333941100 PMID: 12907699 31. Pitcher TJ, Morato T, Hart PJ, Clark MR, Haggan N, Santos RS. The depths of ignorance: an ecosys- tem evaluation framework for seamount ecology, fisheries and conservation. In: Pitcher TJ, Morato T, Hart PJ, Clark MR, Haggan N, Santos RS, editors. Seamounts: ecology, fisheries and conservation. Oxford, UK: Blackwell Fisheries and Aquatic Resources Series; 2007. pp. 476–488. 32. Clark MR, Rowden AA, Schlacher T, Williams A, Consalvey M, Stocks KI, et al. The ecology of sea- mounts: structure, function, and human impacts. Annual Review of Marine Science. 2010; 2: 253–278.

https://doi.org/10.1146/annurev-marine-120308-081109 PMID: 21141665 33. Rogers AD. The biology of seamounts: 25 Years on. Advances in Marine Biology. 2018; 79: 137–224. https://doi.org/10.1016/bs.amb.2018.06.001 PMID: 30012275 34. McClain CR, Lundsten L, Barry J, DeVogelaere A. Assemblage structure, but not diversity or density, change with depth on a northeast Pacific seamount. Marine Ecology. 2010; 31: 14–25. 35. Mejı´a-Mercado BE, Mundy B, Baco AR. Variation in the structure of the deep-sea fish assemblages on Necker Island, Northwestern Hawaiian Islands. Deep Sea Research Part I: Oceanographic Research Papers. 2019; 152: 103086. 36. Watling L, Norse EA. Disturbance of the seabed by mobile fishing gear: a comparison to forest clear- cutting. Conservation Biology. 1998; 12(6): 1180–1197. 37. Williams A, Schlacher TA, Rowden AA, Althaus F, Clark MR, Bowden DA, et al. Seamount mega- benthic assemblages fail to recover from trawling impacts. Marine Ecology. 2010; 31: 183–199. 38. Clark MR. Deep-sea seamount fisheries: a review of global status and future prospects. Latin Ameri- can Journal of Aquatic Research. 2009; 37(3): 501–512. 39. Baco AR, Roark EB, Morgan NB. Amid fields of rubble, scars, and lost gear, signs of recovery observed on seamounts on 30-to 40-year time scales. Science Advances. 2019; 5(8): eaaw4513. https://doi.org/10.1126/sciadv.aaw4513 PMID: 31457086 40. Appeltans W, Ahyong ST, Anderson G, Angel MV, Artois T, Bailly N, et al The magnitude of global marine species diversity. Current Biology. 2012; 22(23): 2189–2202. https://doi.org/10.1016/j.cub.

2012.09.036 PMID: 23159596 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 23 / 27

41. Ga´ lvez-Larach M. Seamounts of Nazca and Salas y Go´ mez: a review for management and conserva- tion purposes. Latin American Journal of Aquatic Research. 2009; 37(3): 497–500. 42. Gove JM, McManus MA, Neuheimer AB, Polovina JJ, Drazen JC, Smith CR, et al. Near-island biologi- cal hotspots in barren ocean basins. Nature Communications. 2016; 7(1): 1–8. https://doi.org/10. 1038/ncomms10581 PMID: 26881874 43. Sandin SA, Smith JE, DeMartini EE, Dinsdale EA, Donner SD, Friedlander AM, et al. Baselines and degradation of coral reefs in the Northern Line Islands. PloS ONE. 2008; 3(2): e1548. https://doi.org/ 10.1371/journal.pone.0001548 PMID: 18301734 44. DeMartini EE, Friedlander AM, Sandin SA, Sala E. Differences in fish-assemblage structure between fished and unfished atolls in the northern Line Islands, central Pacific. Marine Ecology Progress Series. 2008; 365: 199–215. 45. Giddens J, Goodell W, Friedlander A, Salinas-de-Leo´n P, Shepard C, Henning B, et al. Patterns in bathyal demersal biodiversity and community composition around archipelagos in the Tropical Eastern Pacific. Frontiers in Marine Science. 2019; 6: 388. 46. Friedlander AM, Giddens J, Ballesteros E, Blum S, Brown EK, Caselle JE, et al. Marine biodiversity from zero to a thousand meters at Clipperton Atoll (Iˆle de La Passion), Tropical Eastern Pacific. PeerJ. 2019; 7: e7279. https://doi.org/10.7717/peerj.7279 PMID: 31341739 47. Parin NV, Shcherbachev YN. Two new argentinine fishes of the genus Glossanodon from the eastern South Pacific. Japanese Journal of Ichthyology. 1982; 28(4): 381–384.

48. Anderson WD, Springer VG. Review of the perciform fish genus Symphysanodon Bleeker (Symphysa- nodontidae), with descriptions of three new species, S. mona, S. parini, and S. rhax. Zootaxa. 2005; 996(1): 1–44. 49. Sellanes J, Salisbury RA, Tapia JM, Asorey CM. A new species of Atrimitra Dall, 1918 (Gastropoda: Mitridae) from seamounts of the recently created Nazca-Desventuradas Marine Park, Chile. PeerJ. 2019; 7: e8279. https://doi.org/10.7717/peerj.8279 PMID: 31875160 50. Comite´ Oceanogra´ fico Nacional de Chile 2017. Crucero CIMAR 22 Islas Ocea´ nicas (13 de octubre al 14 de noviembre de 2016) resultados preliminares. 130 pp. 51. Ferna´ndez M, Hormaza´ bal S. Overview of recent advances in oceanographic, ecological and fisheries research on oceanic islands in the southeastern Pacific Ocean. Latin American Journal of Aquatic Research. 2014; 42(4): 666–672. 52. Easton EE, Sellanes J, Gaymer CF, Morales N, Gorny M, Berkenpas E. Diversity of deep-sea fishes of the Easter Island Ecoregion. Deep Sea Research Part II: Topical Studies in Oceanography. 2017; 137: 78–88. 53. Wagner D, Friedlander AM, Pyle PL, Brooks CM, Gjerde KM, Wilhelm TA. Coral reefs of the high seas: hidden biodiversity hotspots in need of protection. Frontiers in Marine Science. 2021; https://doi. org/10.3389/fmars.2020.567428 54. Friedlander AM, Ballesteros E, Beets J, Berkenpas E, Gaymer CF, Gorny M, et al. Effects of isolation and fishing on the marine ecosystems of Easter Island and Salas y Go´mez, Chile. Aquatic Conserva- tion: Marine and Freshwater Ecosystems. 2013; 23(4): 515–531.

55. Turchik AJ, Berkenpas EJ, Henning BS, Shepard CM. The Deep Ocean Dropcam: A highly deployable benthic survey tool. OCEANS 2015—MTS/IEEE Washington. Institute of Electrical and Electronics Engineers Inc.; 2016. https://doi.org/10.1177/1524838014566721 PMID: 25612800 56. Spalding MD, Fox HE, Allen GR, Davidson N, Ferdaña ZA, Finlayson MA, et al. Marine ecoregions of the world: a bioregionalization of coastal and shelf areas. BioScience. 2007; 57(7): 573–583. 57. Mieth A, Bork HR. History, origin and extent of soil erosion on Easter Island (Rapa Nui). Catena. 2005; 63(2–3): 244–260. 58. Fisher RL, Norris RM. Bathymetry and geology of Sala y Gomez, southeast Pacific. Geological Society of America Bulletin. 1960; 71(4): 497–502. 59. Newman WA, Foster BA. The Rapanuian faunal district (Easter and Sala y Gomez): In search of ancient archipelagos. Bulletin of Marine Science. 1983; 33(3): 633–644. 60. Ray JS, Mahoney JJ, Duncan RA, Ray J, Wessel P, Naar DF. Chronology and geochemistry of lavas from the Nazca Ridge and Easter Seamount Chain: an* 30 Myr hotspot record. Journal of Petrology. 2012; 53(7): 1417–1448. 61. Giddens J, Turchik A, Goodell W, Rodriguez M, Delaney D. The National Geographic Society Deep- Sea Camera System: A Low-Cost Remote Video Survey Instrument to Advance Biodiversity Observa- tion in the Deep Ocean. Frontiers in Marine Science. 2021; 7:1157. https://doi.org/10.3389/fmars. 2020.601411 62. University of Hawai‘i Undersea Research Laboratory (HURL) Deep-sea Animal Identification Guide.

Available from http://www.soest.hawaii.edu/,HURL/HURLarchive/guide.php 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 24 / 27

63. Froese R, Pauly D. Editors. 2020. FishBase.World Wide Web electronic publication. www.fishbase. org, (12/2020) 64. Dyer BS, Westneat MW. Taxonomy and biogeography of the coastal fishes of Juan Ferna´ndez Archi- pelago and Desventuradas Islands, Chile. Revista de Biologı´a Marina y Oceanografı´a. 2010; 45(1): 589–617. 65. Parin NV. Fish fauna of the Nazca and Sala y Gomez submarine ridges, the easternmost outpost of the Indo-West Pacific zoogeographic region. Bulletin of Marine Science. 1991; 49(3): 671–683. 66. Parin NV, Mironov AN, Nesis KN. Biology of the Nazca and Sala y Gomez submarine ridges, an out- post of the Indo-West Pacific fauna in the eastern Pacific Ocean: composition and distribution of the fauna, its communities and history. Advances in Marine Biology. 1997; 32: 145–242. 67. Randall JE, Cea A. Shore fishes of Easter Island. Honolulu, Hawaii: University of Hawaii Press; 2011. 68. Langlois T, Goetze J, Bond T, Monk J, Abesamis RA, Asher J, et al. A field and video annotation guide for baited remote underwater stereo-video surveys of demersal fish assemblages. Methods in Ecology and Evolution. 2020; 11(11): 1401–1409. 69. Ardron JA, Clark MR, Penney AJ, Hourigan TF, Rowden AA, Dustan PK, et al. A systematic approach towards the identification and protection of vulnerable marine ecosystems. Marine Policy. 2014; 49: 146–154. 70. Davies JS, Stewart HA, Narayanaswamy BE, Jacobs C, Spicer J, Golding N, et al. Benthic assem- blages of the Anton Dohrn Seamount (NE Atlantic): defining deep-sea biotopes to support habitat

mapping and management efforts with a focus on vulnerable marine ecosystems. PLOS ONE. 2015; 10(5): e0124815. https://doi.org/10.1371/journal.pone.0124815 PMID: 25992572 71. Sayre RG, Wright DJ, Breyer SP, Butler KA, Van Graafeiland K, Costello MJ, et al. A three-dimen- sional mapping of the ocean based on environmental data. Oceanography. 2017; 30(1): 90–103. 72. Lutz MJ, Caldeira K, Dunbar RB, Behrenfeld MJ. Seasonal rhythms of net primary production and par- ticulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean. Journal of Geophysical Research: Oceans. 2007; 112: C10011. 73. Watling L, Guinotte J, Clark MR, Smith CR. A proposed biogeography of the deep ocean floor. Prog- ress in Oceanography. 2013; 111: 91–112. 74. Kim SS, Wessel P. New global seamount census from altimetry-derived gravity data. Geophysical Journal International. 2011; 186(2): 615–631. 75. Mu¨ ller RD, Sdrolias M, Gaina C, Roest WR. Age, spreading rates, and spreading asymmetry of the world’s ocean crust. Geochemistry, Geophysics, Geosystems. 2008; 9(4): Q04006. 76. Jones DO, Brewer ME. Response of megabenthic assemblages to different scales of habitat hetero- geneity on the Mauritanian slope. Deep Sea Research Part I: Oceanographic Research Papers. 2012; 67: 98–110. 77. Lundblad EM, Wright DJ, Miller JO, Larkin EM, Rinehart RO, Battista T, et al. Classifying benthic ter- rains with multibeam bathymetry, bathymetric position and rugosity: Tutuila, American Samoa. Marine Geodesy. 2006; 29(2): 89–111.

78. Wright DJ, Pendleton M, Boulware J, Walbridge S, Gerlt B, Eslinger D, et al. ArcGIS Benthic Terrain Modeler (BTM), v. 3.0, Environmental Systems Research Institute, NOAA Coastal Services Center, Massachusetts Office of Coastal Zone Management. Available online at http://esriurl.com/5754. 2012. 79. Walbridge S, Slocum N, Pobuda M, Wright DJ. Unified geomorphological analysis workflows with Ben- thic Terrain Modeler. Geosciences. 2018; 8(3): 94. 80. Ryan WB, Carbotte SM, Coplan JO, O’Hara S, Melkonian A, Arko R, et al. Global multi-resolution topography synthesis. Geochemistry, Geophysics, Geosystems. 2009; 10(3): Q03014. 81. Dolan MF, Grehan AJ, Guinan JC, Brown C. Modelling the local distribution of cold-water corals in relation to bathymetric variables: Adding spatial context to deep-sea video data. Deep Sea Research Part I: Oceanographic Research Papers. 2008; 55(11): 1564–1579. 82. Leitner AB, Neuheimer AB, Donlon E, Smith CR, Drazen JC. Environmental and bathymetric influ- ences on abyssal bait-attending communities of the Clarion Clipperton Zone. Deep Sea Research Part I: Oceanographic Research Papers. 2017; 125: 65–80. 83. Ludwig JA, Reynolds JF. Statistical Ecology. New York, New York: John Wiley and Sons; 1998. 84. ter Braak CJ, Prentice IC. A theory of gradient analysis. Advances in Ecological Research. 2004; 34: 235–282. 85. Zar JH. Biostatistical analysis. 5th ed. Indiana: Pearson; 2009. 86. Shank TM. Seamounts: deep-ocean laboratories of faunal connectivity, evolution, and endemism. Oceanography. 2010; 23(1): 108–122. 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 25 / 27

87. Yeh J, Drazen JC. Depth zonation and bathymetric trends of deep-sea megafaunal scavengers of the Hawaiian Islands. Deep Sea Research Part I: Oceanographic Research Papers. 2009; 56(2): 251– 266. 88. Victorero L, Robert K, Robinson LF, Taylor ML, Huvenne VA. Species replacement dominates mega- benthos beta diversity in a remote seamount setting. Scientific Reports. 2018; 8: 4152. https://doi.org/ 10.1038/s41598-018-22296-8 PMID: 29515196 89. Rodrigo C, Lara LE. Plate tectonics and the origin of the Juan Ferna´ ndez Ridge: analysis of bathyme- try and magnetic patterns. 2014. Latin American Journal of Aquatic Research 42: 666–672. 90. Delrieu-Trottin EL, Brosseau-Acquaviva S, Mona V, Neglia EC, Giles C, Rapu-Edmunds, et al. Under- standing the origin of the most isolated endemic reef fish fauna of the Indo-Pacific: coral reef fishes of Rapa Nui. Journal of Biogeography. 2019; 46: 723–733. 91. Ernst B, Chamorro J, Manrı´quez P, Orensanz JL, Parma AM, Porobic J, et al. Sustainability of the Juan Ferna´ ndez lobster fishery (Chile) and the perils of generic science-based prescriptions. Global Environmental Change. 2013; 23(6):1381–1392. 92. Ahumada M, Arana PM. Artisanal fishing for golden crab (Chaceon chilensis) off the Juan Ferna´ ndez archipelago, Chile. Latin American Journal of Aquatic Research. 2009; 37(3): 285–296. 93. Friedlander AM, Gaymer CF. Progress, opportunities and challenges for marine conservation in the Pacific Islands. Aquatic Conservation: Marine and Freshwater Ecosystems. 2021; 31(2): 221–231.

94. Ahumada M, Queirolo D. Explotacio´ n de peces asociada a la pesquerı´a artesanal de langosta de Juan Ferna´ ndez (Jasus frontalis). Latin American Journal of Aquatic Research. 2014; 42(1): 213–223. 95. Roark EB, Guilderson TP, Dunbar RB, Fallon SJ, Mucciarone DA. Extreme longevity in proteinaceous deep-sea corals. Proceedings of the National Academy of Sciences. 2009; 106(13): 5204–5208. https://doi.org/10.1073/pnas.0810875106 PMID: 19307564 96. Schiller L, Bailey M, Jacquet J, Sala E. High seas fisheries play a negligible role in addressing global food security. Science Advances. 2018; 4(8): eaat8351. https://doi.org/10.1126/sciadv.aat8351 PMID: 30101196 97. Sala E, Mayorga J, Costello C, Kroodsma D, Palomares ML, Pauly D, et al. The economics of fishing the high seas. Science Advances. 2018; 4(6): eaat2504. https://doi.org/10.1126/sciadv.aat2504 PMID: 29881780 98. Sumaila UR, Lam VW, Miller DD, Teh L, Watson RA, Zeller D, et al. Winners and losers in a world where the high seas is closed to fishing. Scientific Reports. 2015; 5(1): 1–6. 99. Cheung W, Levin L. Model-averaging time of emergence of climate change in each RFMO area. In: Deep-ocean climate change impacts on habitat, fish and fisheries. Levin L, Baker M, Thompson A, edi- tors. Rome: FAO Fisheries and Aquaculture Technical Paper No. 638; 2018. pp. 60–99. 100. Andrade I, Hormaza´ bal S, Correa-Ramı´rez M. Time-space variability of satellite chlorophyll-a in the Easter Island Province, southeastern Pacific Ocean. Latin American Journal of Aquatic Research. 2014; 42(4): 871–887.

101. Pinsky ML, Eikeset AM, McCauley DJ, Payne JL, Sunday JM. Greater vulnerability to warming of marine versus terrestrial ectotherms. Nature. 2019; 569(7754):108–111. https://doi.org/10.1038/ s41586-019-1132-4 PMID: 31019302 102. Dulvy NK, Sadovy Y, Reynolds JD. Extinction vulnerability in marine populations. Fish and Fisheries. 2003; 4(1):25–64. 103. Cheung WW, Lam VW, Sarmiento JL, Kearney K, Watson RE, Zeller D, et al. Large-scale redistribu- tion of maximum fisheries catch potential in the global ocean under climate change. Global Change Biology. 2010; 16(1): 24–35. 104. Convention on Biological Diversity (CBD). Decision adopted by the Conference of the Parties to the Convention on Biological Diversity. Conference of the Parties to the Convention on Biological Diversity Twelfth Meeting. Pyeongchang, Republic of Korea, 6–17 October 2014. Agenda item 21. 59 pp. Avail- able at: https://www.cbd.int/doc/decisions/cop-12/cop-12-dec-22-en.pdf 105. Thiel M, Macaya EC, Acuña E, Arntz WE, Bastias H, Brokordt K, et al. The Humboldt current system of northern and central Chile. Oceanographic processes, ecological interactions and socioeconomic feedback. Oceanography and Marine Biology: An Annual Review. 2007; 45: 195–344. https://doi.org/ 10.1201/9781420050943 106. Arcos DF, Cubillos LA, Nu´nez SP. The jack mackerel fishery and El Niño 1997–98 effects off Chile. Progress in Oceanography. 2001; 49(1–4): 597–617. 107. Ga´ lvez M. Description of area meeting CBD’s criteria in the Eastern Tropical and Temperate Pacific

Region. Area: Salas y Go´mez and Nazca Ridges, Convention on Biological Diversity. 2012. 6 pp. Available at: https://www.cbd.int/doc/meetings/mar/ebsa-ettp-01/other/ebsa-ettp-01-wwfchile-02-en. pdf6. 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 26 / 27

108. Ya´ñez E, Silva C, Marabolı´ J, Go´ mez F, Silva N, O´ rdenes A, et al. A´ rea marina de proteccio´n de la bio- diversidad de recursos pela´ gicos en los montes submarinos de la Cordillera Nazca. Ape´ ndice modelo para la presentacio´ n de la informacio´ n cientı´fica para la descripcio´ n de a´ reas marinas de importancia ecolo´ gica o biolo´ gica, Conv. Sobre la Divers. Biolo´ gica 5 (2012). 109. Hucke-Gaete R, Aguayo-Lobo A, Yancovic-Pakarati S, Flores M. Marine mammals of Easter Island (Rapa Nui) and Salas y Go´ mez Island (Motu Motiro Hiva), Chile: a review and new records. Latin American Journal of Aquatic Research. 2014; 42(4): 743–751. 110. CBD 2017. Ecologically or Biologically Significant Areas (EBSAs)—Dorsal de Nazca y de Salas y Go´ mez (Salas y Go´mez and Nazca Ridges). 8 pp. 111. SERNANP 2020. Expediente te´ cnico preliminar: Reserva Nacional Dorsal de Nasca. Mayo 2020. Available online at: h http://www.sernanp.gob.pe/reserva-nacional-dorsal-de-nasca i. 112. Sala E, Mayorga J, Bradley D, Cabral R, Atwood TB, Auber A, et al. Protecting the global ocean for biodiversity, food and climate. Nature. 2021; 592: 397–402. https://doi.org/10.1038/s41586-021- 03371-z PMID: 33731930 113. Zhao Q, Stephenson F, Lundquist C, Kaschner K, Jayathilake D, Costello MJ. Where Marine Pro- tected Areas would best represent 30% of ocean biodiversity. Biological Conservation. 2020; 244: 108536. 114. Visalli ME, Best BD, Cabral RB, Cheung WW, Clark NA, Garilao C, et al. Data-driven approach for

highlighting priority areas for protection in marine areas beyond national jurisdiction. Marine Policy. 2020; 122: 103927. 115. Clark N, Reville G. A path to creating the first generation of high seas protected areas—science-based method highlights 10 sites that would help safeguard biodiversity beyond national waters, PEW Chari- table Trusts 42 (2020). 116. Clark MR, Rowden AA, Schlacher TA, Guinotte J, Dunstan PK, Williams A, et al. Identifying Ecolog- ically or Biologically Significant Areas (EBSA): a systematic method and its application to seamounts in the South Pacific Ocean. Ocean & Coastal Management. 2014; 91: 65–79. 117. Lucifora LO, Garcı´a VB, Worm B. Global diversity hotspots and conservation priorities for sharks. PloS ONE. 2011; 6(5): e19356. https://doi.org/10.1371/journal.pone.0019356 PMID: 21573162 118. Georgian SE, Morgan L, Wagner D (in review). The modeled distribution of corals and sponges sur- rounding the Salas y Go´ mez and Nazca ridges with implications for high seas conservation. PeerJ. 119. Mayer L, Jakobsson M, Allen G, Dorschel B, Falconer R, Ferrini V, et al. The Nippon Foundation— GEBCO seabed 2030 project: The quest to see the world’s oceans completely mapped by 2030. Geo- sciences. 2018; 8(2): 63–81. 120. Bailey DM, King NJ, Priede IG. Cameras and carcasses: historical and current methods for using artifi- cial food falls to study deep-water animals. Marine Ecology Progress Series. 2007; 350: 179–191. 121. Priede IG, Bagley PM. In situ studies on deep-sea demersal fishes using autonomous unmanned

lander platforms. Oceanography and Marine Biology. 2000; 38: 357–392. 122. Jetz W, McGeoch MA, Guralnick R, Ferrier S, Beck J, Costello MJ, et al Essential biodiversity vari- ables for mapping and monitoring species populations. Nature Ecology & Evolution. 2019; 3(4): 539– 551. https://doi.org/10.1038/s41559-019-0826-1 PMID: 30858594 123. Yeh J, Drazen JC. Baited-camera observations of deep-sea megafaunal scavenger ecology on the California slope. Marine Ecology Progress Series. 2011; 424: 145–156. 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 27 / 27