Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • BCO-DMO Processing Description
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

See the "Related Datasets" section for additional scientific sample lists, dive summaries, and related datasets from this cruise. Samples from this cruise include: benthic invertebrate samples collected by ROV Jason, plankton samples collected with the SyPRID sampler on Sentry, and water samples collected with niskin bottles on the CTD carousel.

Water samples were collected via 4-L niskin bottles on the ship's CTD carousel and filtered for a variety of studies. 

Data submission included three separate sample lists supplied as separate sheets in the same excel file TN-391 Master Sample List.xlsx (each became a BCO-DMO dataset, see "Related Datasets").

Data File:

- Loaded data from "TN-391 Master Sample List.xlsx", sheet "CTD", using rows 1-2 as headers, skipping row 1, treating "N/A" as missing values.
- Data did not contain latitude and longitude so the Cast_Lat, and Cast_Lon were aquired from R2R Underway CTD dataset (doi:10.7284/150390) .hdr files (NMEA Lat, and Lon) which were then added to the water sample list
- Converted "Cast_Lat" and "Cast_Lon" fields from degrees-decimal_minutes format (with directional indicators N/S and E/W respectively) to decimal degrees
- Rounded "Cast_Lat" and "Cast_Lon" to 5 decimal places
- Applied BCO-DMO field metadata (descriptions, standard name IDs, supplied units) to fields: Site, Date, Depth, Niskin #, Container, Volume Filtered, Filter Type, Preservation, Recipient of Sample
- Removed trailing "m" suffix from Depth field values to allow numeric typing (e.g., "25m" → "25")
- Set field types: Date as date (%Y-%m-%d), Depth as integer, all other fields as string
- Renamed columns to meet BCO-DMO naming conventions designed for interoperability: "Niskin #" → "Niskin_num", "Volume Filtered" → "Volume_Filtered", "Filter Type" → "Filter_Type", "Recipient of Sample" → "Recipient_of_Sample"
- Updated package-level metadata with field-level statistics (counts, min/max values) for all columns across 71 rows
- Output saved to "945088_v1_tn391-water-sample-list.csv"

Metadata:
- Parameter (column) descriptions filled in from a related dive summary dataset also used to fill in definitions (see "Related Datasets").
- Exact Instrument model for the cruise added from listing at Rolling Deck to Repository (R2R) for this cruise.

NSF Award Abstract:
Ever since hydrothermal vents and methane seeps were first discovered in the deep ocean more than 40 years ago, scientists have wondered how these isolated communities, fully dependent on underwater "islands" of toxic chemicals, are first colonized by organisms, and how the populations of these specialized animals are exchanged and maintained. These fundamental processes depend on the transport of babies (larvae) by the ocean currents, yet because the larvae are microscopic and diluted in the vastness of the ocean, it is very difficult to determine where and how they drift. This project uses an autonomous underwater vehicle to collect larvae from precise regions of the water column. Larval traps on the bottom and chemical analyses of larval shells will also be used to determine the depths where larvae swim. These findings will provide realistic estimates for mathematical models that show how biology interacts with ocean currents to predict which methane seeps will be colonized by larvae originating at different depths. A detailed knowledge of larval dispersal is needed for conservation and management of the deep sea. Without such information, we cannot know the best placement of marine protected areas, nor can we facilitate the reestablishment of communities impacted by deep-sea mining, drilling, or other human activities. This project will provide hands-on at-sea training for college students to learn the rapidly vanishing skills needed for studies of larvae and embryos in their natural habitats. Learning opportunities will also be available to individuals of all ages through new, interactive exhibits on deep-sea biology and larval ecology produced for small museums and aquaria on the coasts of Oregon, Washington and North Carolina.

Reliable estimates of connectivity among metapopulations are increasingly important in marine conservation biology, ecology and phylogeography, yet biological parameters for biophysical models in the deep sea remain largely unavailable. The movements of deep-sea vent and seep larvae among islands of habitat suitable for chemosynthesis have been inferred from current patterns using numerical modeling, but virtually all such models have used untested assumptions about biological parameters that should have large impacts on the predictions. This project seeks to fill in the missing biological parameters while developing better models for predicting the dispersal patterns of methane seep animals living in the Gulf of Mexico and on the Western Atlantic Margin. Despite the existence of similar seeps at similar depths on two sides of the Florida peninsula, the Western Atlantic seeps support only a subset of the species found in the Gulf of Mexico. It is hypothesized that the ability of larvae to disperse through the relatively shallow waters of the Florida Straits depends on an interaction between the adult spawning depth and the dispersal depth of the larvae. Dispersal depth, in turn, will be influenced by larval flotation rates, swimming behaviors, feeding requirements, and ontogenetic migration patterns during the planktonic period. The recently developed SyPRID sampler deployed on AUV Sentry will be used to collect larvae from precise depth strata in the water column, including layers very near the ocean floor. Larval traps deployed on the bottom at three depths in each region will be used in conjunction with the plankton collections to determine what proportion of larvae are demersal. Comparisons of stable oxygen isotopes between larval and juvenile mollusk shells will provide information on the temperatures (and therefore depths) that larvae develop, and geochemical analyses of larval and juvenile shells will determine whether larval cohorts mix among depth strata. Ocean circulation and particle transport modeling incorporating realistic biological parameters will be used to predict the movements of larvae around the Florida Peninsula for various spawning depths and seasons.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.