Oceanographic drivers of deep-sea coral species distribution and community assembly on seamounts, islands, atolls, and reefs within the Phoenix Islands Protected Area

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Auscavitch, S. R., Deere, M. C., Keller, A. G., Rotjan, R. D., Shank, T. M., & Cordes, E. E. Oceanographic drivers of deep-sea coral species distribution and community assembly on seamounts, islands, atolls, and reefs within the Phoenix Islands Protected Area. Frontiers in Marine Science, 7, (2020): 42, doi:10.3389/fmars.2020.00042.The Phoenix Islands Protected Area, in the central Pacific waters of the Republic of Kiribati, is a model for large marine protected area (MPA) development and maintenance, but baseline records of the protected biodiversity in its largest environment, the deep sea (>200 m), have not yet been determined. In general, the equatorial central Pacific lacks biogeographic perspective on deep-sea benthic communities compared to more well-studied regions of the North and South Pacific Ocean. In 2017, explorations by the NOAA ship Okeanos Explorer and R/V Falkor were among the first to document the diversity and distribution of deep-water benthic megafauna on numerous seamounts, islands, shallow coral reef banks, and atolls in the region. Here, we present baseline deep-sea coral species distribution and community assembly patterns within the Scleractinia, Octocorallia, Antipatharia, and Zoantharia with respect to different seafloor features and abiotic environmental variables across bathyal depths (200–2500 m). Remotely operated vehicle (ROV) transects were performed on 17 features throughout the Phoenix Islands and Tokelau Ridge Seamounts resulting in the observation of 12,828 deep-water corals and 167 identifiable morphospecies. Anthozoan assemblages were largely octocoral-dominated consisting of 78% of all observations with seamounts having a greater number of observed morphospecies compared to other feature types. Overlying water masses were observed to have significant effects on community assembly across bathyal depths. Revised species inventories further suggest that the protected area it is an area of biogeographic overlap for Pacific deep-water corals, containing species observed across bathyal provinces in the North Pacific, Southwest Pacific, and Western Pacific. These results underscore significant geographic and environmental complexity associated with deep-sea coral communities that remain in under-characterized in the equatorial central Pacific, but also highlight the additional efforts that need to be brought forth to effectively establish baseline ecological metrics in data deficient bathyal provinces.Funding for this work was provided by NOAA Office of Ocean Exploration and Research (Grant No. NA17OAR0110083) to RR, EC, TS, and David Gruber

Exploration of the Windward Passage and Jamaica Channel: Tectonic Gateways to the Caribbean Sea

The Ocean Exploration Trust (OET) Workshop on Telepresence-Enabled Exploration of the Caribbean Region was convened in November 2012 to plan for the 2013 field season with the idea that Exploration Vessel (E/V) Nautilus and its Corps of Exploration would spend only one year working in the Gulf of Mexico and the Caribbean Sea. However, the strong showing of interest in the area from the international group of marine scientists who submitted white papers to and participated in that workshop was so impressive the Trust and its Nautilus Advisory Board decided to schedule a second year in this area of the world before moving on to the Pacific Ocean, as originally planned. This fifth Oceanography supplement chronicles the 2014 field season: four months of exploration in the Gulf of Mexico and the Caribbean Sea, as well as rapid growth in our science, technology, engineering, and mathematics (STEM) education and outreach programs and continued research on best practices of telepresence and archaeological oceanography

Corrigendum: the unknown and the unexplored: insights into the Pacific deep-sea following NOAA CAPSTONE expeditions

Published versio

The unknown and the unexplored: insights Into the Pacific deep-sea following NOAA CAPSTONE expeditions

Over a 3-year period, the National Oceanic and Atmospheric Administration (NOAA) organized and implemented a Pacific-wide field campaign entitled CAPSTONE: Campaign to Address Pacific monument Science, Technology, and Ocean NEeds. Under the auspices of CAPSTONE, NOAA mapped 597,230 km2 of the Pacific seafloor (with ∼61% of mapped area located within US waters), including 323 seamounts, conducted 187 ROV dives totaling 891.5 h of ROV benthic imaging time, and documented >347,000 individual organisms. This comprehensive effort yielded dramatic insight into differences in biodiversity across depths, regions, and features, at multiple taxonomic scales. For all deep sea taxonomic groups large enough to be visualized with the ROV, we found that fewer than 20% of the species were able to be identified. The most abundant and highest diversity taxa across the dataset were from three phyla (Cnidaria, Porifera, and Echinodermata). We further examined these phyla for taxonomic assemblage patterns by depth, geographic region, and geologic feature. Within each taxa, there were multiple genera with specific distribution and abundance by depth, region, and feature. Additionally, we observed multiple genera with broad abundance and distribution, which may focus future ecological research efforts. Novel taxa, records, and behaviors were observed, suggestive of many new types of species interactions, drivers of community composition, and overall diversity patterns. To date, only 13.8% of the Pacific has been mapped using modern methods. Despite the incredible amount of new known and unknown information about the Pacific deep-sea, CAPSTONE is far from the culminating experience the name suggests. Rather, it marks the beginning of a new era for exploration that will offer extensive opportunities via mapping, technology, analysis, and insights.Published versio

Biogeographic Patterns Among Deep-Sea Benthic Megafaunal Communities Across the Drake Passage (Southern Ocean)

The Southern Ocean has long been recognized as a biogeographic discontinuity for marine organisms. The Drake Passage, a region bounded by the South America shelf to the north and the Western Antarctic Peninsula to the south, represents a convergence of several biogeographic sub-regions, yet many benthic communities throughout the region remain poorly characterized. This work seeks to provide a survey and comparison of nine deep-sea benthic communities across the Drake Passage using recently collected seafloor imagery and environmental data from cruises in 2008 and 2011. Over one thousand images across nine sites were examined for species composition, megafaunal density, and seafloor substrate characteristics. Towed camera observations revealed substantial sponge and coral diversity and abundance among several sites throughout Burdwood Bank, Cape Horn, as well as two offshore seamounts. Sars and Interim Seamounts exhibited multiple unique assemblages of invertebrate faunas including cold-water corals, anemones, and sponges compositionally similar to adjacent shelf environments. Multivariate biogeographic analyses among megafaunal communities suggest bathymetric patterns consistent within major Southern Ocean water masses including Subantarctic Mode Waters, Antarctic Intermediate Waters, and Circumpolar Deep Waters. As a result of this exploratory assessment, seamounts should be a focus of further examination of benthic communities throughout the Southern Ocean to provide insight to the role that these features play in defining regional biogeographic patterns

Exploration of the Mid-Cayman Rise

Mid-Cayman Rise objectives were built on exciting results from a flurry of recent expeditions that investigated hydrothermal sites in the region (German et al., 2010, 2012). The 2013 E/V Nautilus cruise explored oceanic core complexes (OCCs), tall, smooth-sided hills that rise from the seafloor on the flanks of some mid-ocean ridges. Dives (Figure 1) explored the full extent and nature of life around the Von Damm hydrothermal field, previously discovered there, as well as the geology to further understanding of the vents’ origins, and to survey the OCC summits that had never before been investigated by a deep diving vehicle. This 2013 study was the first Nautilus cruise to have more scientists participating in the expedition from locations on shore than from the ship, tripling the size of the science party