FKt230918 expedition – Vertical Reef of the Galapagos

Enregistrements de données

Les données de cette ressource données d'échantillonnage ont été publiées sous forme dune Archive Darwin Core (Darwin Core Archive ou DwC-A), le format standard pour partager des données de biodiversité en tant quensemble dun ou plusieurs tableurs de données. Le tableur de données du cœur de standard (core) contient 671 enregistrements.

2 tableurs de données dextension existent également. Un enregistrement dextension fournit des informations supplémentaires sur un enregistrement du cœur de standard (core). Le nombre denregistrements dans chaque tableur de données dextension est illustré ci-dessous.

Cet IPT archive les données et sert donc de dépôt de données. Les données et métadonnées de la ressource sont disponibles pour téléchargement dans la section téléchargements. Le tableau des versions liste les autres versions de chaque ressource rendues disponibles de façon publique et permet de tracer les modifications apportées à la ressource au fil du temps.

Versions

Le tableau ci-dessous naffiche que les versions publiées de la ressource accessibles publiquement.

Comment citer

Les chercheurs doivent citer cette ressource comme suit:

Yanez Suarez A B, Robert K (2024). FKt230918 expedition – Vertical Reef of the Galapagos. Version 1.2. Memorial University of Newfoundland. Samplingevent dataset. https://doi.org/10.60545/cz8ams

Droits

Les chercheurs doivent respecter la déclaration de droits suivante:

L’éditeur et détenteur des droits de cette ressource est Memorial University of Newfoundland. Ce travail est sous licence Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0.

Enregistrement GBIF

Cette ressource a été enregistrée sur le portail GBIF, et possède lUUID GBIF suivante : 2a796aad-0c69-4f08-a207-f216cc75b466.  Memorial University of Newfoundland publie cette ressource, et est enregistré dans le GBIF comme éditeur de données avec lapprobation du Canada Biodiversity Information Facility.

Mots-clé

corals; Galapagos; Costa Rica; Isla del Coco; macroinvertebrates; deep sea; cold water coral; Falkor (too); FKt230918; vertical reef; benthic; Ecuador; megabenthos; Eastern Tropical Pacific; Specimen; Specimen

Contacts

Couverture géographique

Biological samples were collected from 19 sites around the Galapagos Islands, Ecuador, and two sites near Isla del Coco, Costa Rica. These efforts took place in deep-sea areas within the Galapagos Marine Reserve and Isla del Coco Marine Reserve, both situated in the Eastern Tropical Pacific. The collection was part of a collaborative effort with the Charles Darwin Foundation's "Deep-Ocean Exploration & Conservation" research project and the University of Costa Rica.

Couverture taxonomique

N/A

Couverture temporelle

Données sur le projet

1.0. Shipboard multibeam echosounders provide a smoothed (at ~50-100 m spatial resolution) representation of rough topography, particularly in deeper waters, and as such cannot adequately characterize the vertical dimension of complex 3D seafloor structures. Trawls or towed-camera systems are similarly ineffective in very rugged environments. Consequently, it was not until the 1990’s that vertical deep-sea habitats started being discovered using human-occupied submersibles. Only recently were methods developed to map the heterogeneity of these cliffs at high resolutions, exploiting the extra maneuverability provided by ROVs. However, for the most part, these striking deep-sea landscapes have remained unexplored, even though cliffs provide environmental conditions different from the surrounding terrain, and often host rich communities of fragile suspension feeders. In particular, cliff environments represent an unaccounted cold-water coral (CWC) habitat of global importance. Although difficult to quantify owing to a lack of systematic data, we estimate that, globally, over 6,000 distinct geomorphological features with rocky walls likely harbor CWCs, representing an estimated global surface area equivalent to ~10% of shallow coral reefs. 2) In addition to providing suitable habitat for a range of species, cliff environments are of further interest as, owing to their complex topography, they provide a natural protection for vulnerable coral species against trawling activities, potentially allowing larvae to help recolonize surrounding damaged habitats. However, environmental conditions likely affect the life cycle of these habitats distinctly from other CWC environments. For example, large coral colonies may only grow on rock faces with particular strength properties, currents interact with the steep topography to create complex flow patterns that affect suitability of feeding conditions, and naturally broken pieces of coral accumulate at the base of cliffs rather than contribute to reef development. As such, our proposed scientific voyage aimed to apply new technologies to unveil, for the first time, the environmental drivers of vertical CWC cliff ecosystems. The data we collected will help quantify the contribution of these understudied environments to regional biodiversity before environmental change alters further ecosystem function. 1.1. In addition, the distribution of Cold water corals across oxygen minimum zones was studied in the Galapagos and la Isla del Coco Costa Rica. Cold-water corals (CWC) form oases of life in the deep sea, providing habitat, food, and shelter to marine animals, including commercial species, but are sensitive to increased temperature and low oxygen. The Eastern Tropical Pacific (ETP) is one of the areas of the planet where oxygen minimum zones (OMZ) are naturally large and expected to expand due to ocean warming. However, how oxygen concentrations affect different species of CWC and how these ecosystems may respond to future changes constitute a knowledge gap for this region. Through this research, we will study CWC across the OMZ in two areas located in the ETP: Isla del Coco and The Galápagos. The Galápagos and Isla del Coco are connected through a coalesced chain of seamounts known as the Cocos Ridge, which is characterized by complex topographic settings and the convergence of different currents, promoting the occurrence of diverse sessile species. Owing to a high degree of endemism, these islands have been declared marine protected areas in Ecuador and Costa Rica, respectively, and World Heritage Sites by UNESCO. Our aim is to identify CWC species biodiversity and composition across depth gradients (200 to 2000 m) and traversing OMZ boundaries to determine whether there is a difference in coral communities and populations between islands (the Galápagos and Isla del Coco) and how the environmental variables relate to these differences.

Méthodes déchantillonnage

At sites where previous ship-borne multibeam data was not available, shipboard multibeam acquisition first took place to find target cliffs in areas of known coral presence (800-500 m in depth for primary objectives, with possible dives to 3,000 m for secondary objectives). At each chosen site, on the first dive, the ROV carried out reconnaissance for CWCs, and once a suitable site was selected, an initial video survey of species assemblages was conducted, and biological and geological samples were collected using ROV SuBastian. For several sites in the Galapagos Islands, extra dives were conducted to map the cliff face using the ROV's multibeam sonar and the DVL in ADCP configuration or/and dedicated to ultra-high-resolution mapping using the laser system. Time permitting, in the Galapagos, one final dive was carried out in the deeper region to collect additional fossil coral specimens and lava flow samples to help reconstruct past events and conditions. CTD casts to 2,000 m (or near the seabed) were conducted in the vicinity of the mapped sites to measure the background hydrograph.

Description des étapes de la méthode:

1. The ROV SuBastian was used to collect biological samples, mainly with the manipulator's arms and, to a lesser extent, the hydraulic suction sampler. Only a few species (<5) were bycatches, including a fish and a squid, that came out in the ROV basket and were also fixed as samples (no reported here due to lack of precise geographical information). In total, 457 biological samples recovered in the Galapagos and in la Isla del Coco by ROV SuBastian dives across a depth range of 123 m to 1619 m are reported here. Before SuBastian returned to the surface, the log sheet and the ROV map were used to create labels. The biological samples were processed in the cold room, where each species was labelled with a unique number (e.g., FKT230918_00650). If a sample occurred on another sample (e.g., an ophiuroid on a coral), the relationship was preserved through a “parent-child” chain to ensure that information about associates was retained through the Parent ID field. Several photos of every individual organism with a visible scale bar and label were recorded in the lab to ensure “live” color and state were recorded as soon as possible. A whole animal image and a close-up (when possible) were taken for each organism collected. Each image was then labelled with its unique specimen number. To ensure future genetic research, every hard coral, octocoral and black coral was sub-sampled and preserved in 96% ethanol and stored at – 4°C and - 30°C in 2ml cryotubes; the entire samples were preserved in 70% ethanol and storage in the Charles Darwin Foundation voucher. Coral associated epifaunal organisms were collected, preserved and processed in multiple ways to conduct a variety of studies, including genetic analyses, such as DNA barcoding to identify species, assess phylogenetic/ co-evolutionary relationships and stable carbon isotopes to identify trophic relationships with habitat types (e.g., vertical walls vs. low-relief mounds at different depths). Specifically, samples of coral-associated organisms were subsampled and preserved in either 70% or 96% ethanol for long-term backup storage and genetic analyses. A few samples were fixed in RNA Later for 24 hours at four °C, then moved to -80°C for long-term storage for genetic analyses or flash frozen in liquid nitrogen and stored at -80°C for genetic/isotope analyses. Voucher specimens and specimens too small for multiple subsampling were also preserved in 96% ethanol for the Charles Darwin Foundation and housed at the Research Station for morphological and taxonomic analyses.

Métadonnées additionnelles