FKt230918 expedition – Vertical Reef of the Galapagos

Study Extent

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 done with the collaboration of the Charles Darwin Foundation's "Deep-Ocean Exploration & Conservation" research project and the University of Costa Rica. All methods were carried out in accordance with relevant guidelines and regulations by the Galapagos National Park Department and the Sistema Nacional de Areas de Conservacion.

Sampling

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.

Method steps

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.

N/A

1. NA
   rank: order
2. Mollusca
   rank: phylum
3. Arthropoda
   rank: phylum
4. Scleractinia
   rank: order
5. Polynoidae
   rank: family
6. Hydrozoa
   rank: class
7. Stylasteridae
   rank: family
8. Aquaumbridae
   rank: family
9. Pectinida
   rank: order
10. Chirostylidae
    rank: family
11. Bivalvia
    rank: class
12. Ophiacanthidae
    rank: family
13. Ophiurida
    rank: order
14. Decapoda
    rank: order
15. Octocorallia
    rank: class
16. Porifera
    rank: phylum
17. Asteriidae
    rank: family
18. Phyllodocida
    rank: order
19. Forcipulatida
    rank: order
20. Anthoathecata
    rank: order
21. Sabellida
    rank: order
22. Ophiacanthida
    rank: order
23. Antipatharia
    rank: order
24. Malacalcyonacea
    rank: order
25. Annelida
    rank: phylum
26. NA
    rank: class
27. Polychaeta
    rank: class
28. Scleralcyonacea
    rank: order
29. Chrysogorgiidae
    rank: family
30. Hexacorallia
    rank: class
31. Ophiuroidea
    rank: class
32. Madreporidae
    rank: family
33. Malacostraca
    rank: class
34. Schizopathidae
    rank: family
35. Eunicida
    rank: order
36. NA
    rank: family
37. Asteroidea
    rank: class
38. Dendrophylliidae
    rank: family
39. Cnidaria
    rank: phylum
40. Echinodermata
    rank: phylum

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.