Publications

This report describes the 2016 and 2017 research activities partially or fully funded by the Program to meet NOAA’s mandate to identify, study, and monitor deep-sea coral areas.

ancestral state reconstruction; character evolution; classification; Hexactinellida; integrative systematics; phylogeny; Porifera; total evidence

Glass sponges (Class Hexactinellida) are important components of deep-sea ecosystems and are of interest from geological and materials science perspectives. However, inconsistencies remain that have far-reaching implications for hypotheses about the evolution of their major skeletal construction types (body plans). Here, we increase the taxon sampling of four previously established molecular markers (18S, 28S, and 16S ribosomal DNA, as well as cytochrome oxidase subunit I) by 12 genera, for the first time including representatives of the order Aulocalycoida and the type genus of Dactylocalycidae, taxa that are key to understanding hexactinellid body plan evolution.

The Mountains in the Deep Expedition (EX1705), conducted from April 27, 2017, to May 19, 2017, onboard NOAA Ship Okeanos Explorer, collected valuable new information to support management and science needs throughout the Central Pacific Basin. Operations were conducted in American Samoa and the National Marine Sanctuary of American Samoa, the Cook Islands’ Marae Moana marine park, and in the Jarvis Island and Palmyra Atoll and Kingman Reef Units of the Pacific Remote Islands Marine National Monument (PRIMNM as part of the Campaign to Address Pacific monument Science, Technology, and Ocean NEeds (CAPSTONE).

A new species of Crypthelia, C. kelleyi, is described from a seamount in the Northwestern Hawaiian Islands, making it the fifth species of stylasterid known from the Hawaiian Islands. Collected at 2,116 m, it is the fourth-deepest stylasterid species known.

NOAA and its partners initiated CAPSTONE expeditions aboard Okeanos Explorer in July 2015. In addition to providing valuable information on the habitats and species in these MPAs, CAPSTONE also aims to contribute publicly accessible baseline data and critical information needed to respond to emerging regional issues such as deep-sea mining, sustainable deep-sea fisheries, and potential US ECS designation.

The relationships between tectonic processes, magmatism, and hydrothermal venting along ∼600 km of the slow-spreading Mariana back-arc between 12.7°N and 18.3°N reveal a number of similarities and differences compared to slow-spreading mid-ocean ridges. Analysis of the volcanic geomorphology and structure highlights the complexity of the back-arc spreading center. Here, ridge segmentation is controlled by large-scale basement structures that appear to predate back-arc rifting.

Coelenterata; Antipathidae; Aphanipathidae; deep-sea coral; mesophotic coral ecosystem; Myriopathidae

The black coral fauna of Bermudan waters is poorly known, in large part due to the logistical challenges of surveying deep-water (>50 m) environments where most species occur. In 2016, the Nekton Expedition sought to survey the deep-water biodiversity around Bermuda using manned submersibles and mixed-gas technical SCUBA. A total of 28 black coral specimens were collected, and these were examined based on skeletal spine morphology, polyp morphology, colony branching pattern and in situ photographs. 

Colonies of the holaxonian Calcigorgia spiculifera were tagged beginning in 1999 at three sites in Chatham Strait, Southeast Alaska, using scuba and their growth measured annually for up to 5 years. Colonies were video recorded, and computer image analysis tools provided calibration of video images for measuring the length of several branches. 

deep-sea corals; paleoclimate; oxygen isotope; clumped isotope; boron isotope; SIMS; vital effect

Recent work demonstrates that bamboo coral growth temperature, averaged over its entire lifespan, can be derived from linear correlations in its carbon and oxygen isotope composition (δ13C, δ18O) when the apparent equilibrium fractionations for a coral's growth rate and calcifying pH are used. Building on this method, this study applies it to coeval coral skeleton to assess the possibility of extracting paleoceanographic timeseries from bamboo coral skeletons.

Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska's marine waters, and are associated with many different species of fishes and invertebrates. These ecosystems are vulnerable to the effects of commercial fishing activities and climate change. We compared four commonly used species distribution models (general linear models, generalized additive models, boosted regression trees and random forest models) and an ensemble model to predict the presence or absence and abundance of six groups of benthic invertebrate taxa in the Gulf of Alaska.