Abstract:

This dataset contains bongo sample collection data and the associated zooplankton and ichthyoplankton data obtained aboard the R/V Point Sur cruise BCS01 in the northern Gulf of Mexico during the Bonnet Carré Spillway (BCS) from 2016-02-10 to 2016-02-12. Sub-surface plankton samples were collected using a bongo net (0.5 m diameter) fitted with 202-µm and 333-µm mesh nets. The bongo was fished for 10-minutes just below the surface (0.5-1.5 m) at stations in the Chandeleur Sound, offshore of the Mississippi River delta, and along Alabama shelf to assess the horizontal distribution of plankton in response to the opening of the Bonnet Carré Spillway and high freshwater discharge. In order to assess the horizontal distribution of plankton in response to the opening of the BCS and high freshwater discharge, zooplankton and ichthyoplankton were sorted from the bongo net samples, identified, and enumerated. The cruise BCS01 was led by chief scientist Dr. Christian Briseño-Avena. CTD profiles (temperature, salinity, depth) are available under GRIIDC Unique Dataset Identifier (UDI): R4.x260.000:0044 (DOI: 10.7266/N73B5XKG).

Suggested Citation:

Carla Culpepper, Angie Hoover, Frank Hernandez. 2019. Bongo sample data and the associated zooplankton and ichthyoplankton data collected aboard R/V Point Sur cruise BCS01 in the northern Gulf of Mexico during the Bonnet Carré Spillway from 2016-02-10 to 2016-02-12. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-5faw-an77

Publications:

Parra, S. M., Sanial, V., Boyette, A. D., Cambazoglu, M. K., Soto, I. M., Greer, A. T., … Dinniman, M. S. (2020). Bonnet Carré Spillway freshwater transport and corresponding biochemical properties in the Mississippi Bight. Continental Shelf Research, 199, 104114. doi:10.1016/j.csr.2020.104114

Purpose:

In response to the opening of the Bonnet Carré Spillway, CONCORDE, in collaboration with other GoMRI consortia ECOGIG, ACER, DEEPEND, and CARTHE, organized a response to address the physical and ecological impacts of a large freshwater diversion on regional coastal ecosystems.

Data Parameters and Units:

The worksheet "Read Me File": Contains the general notes and description of the data parameters included in the following worksheet. It also includes zooplankton processing information. The worksheet "NOAA NODC Codes": Contains the National Oceanic and Atmospheric Administration (NOAA) National Oceanographic Data Center Codes on wind speed, wind direction, sea state, and weather. The worksheet "Station and Field Data": Tow Number, Cruise (BCS01), Date (MM/DD/YYYY, UTC), Station, CONCORDE sample number, Water Depth (m), Wind Speed, Wind Direction, Sea State, Weather State, Start Time (UTC), Start Latitude (degrees), Start Latitude (minutes), Start Longitude (degrees), Start Longitude (minutes), End Time (UTC), End Latitude (degrees), End Latitude (minutes), End Longitude (degrees), End Longitude (minutes), Mesh size (µm). The worksheet "Zooplankton Data": Cruise, Sample Date (MMDDYYYY, UTC), Station, Gear, Tow #, Sample ID, Net #, Depth Bin Category, Mesh Size (um), Swept Volume (m3), Plankton Displacement Vol (ml), Individual count (Actinula larvae, Amphipod, Anthozoan larvae, Ascidian larvae, Barnacle cyprid, Barnacle nauplii, Bivalve larvae, Brachiopoda (lingula larva), Calanoid copepod, Cephalopod, Chaetognath, Cladoceran, Copepod nauplii, Crab megalopa, Crab zoea, Ctenophores (larval), Cumacean, Cyclopoid copepod, Doliolid, Echinoderm, Ectoprocta (Bryozoa larvae), Ephyra, Euphausiid , Gastropod larvae, Harpacticoid copepod, Heteropod, Hydroid polyps, Hydromedusae, Isopod, Juvenile Crab, Lancelet, Larvacean, Stomatopods, Lobster larvae, Mysid shrimp, Nematoda, Nemertean pilidium, Nudibranchs, Ostracod, Other decapod, Parasitic copepod, Phoronida (actinotroch larvae), Platyhelminthes (flatworms), Polychaete larvae (trochophores), Polychaete, Pteropod, Pycnogonids, Salps, Scyphomedusae, Siphonophore, Sipunculid, Stomatopod, Tornaria Larvae, Unidentified organisms). The worksheet "Ichthyoplankton Data": Cruise (BCS01), Sample Date (MM/DD/YYYY, UTC), Station, Gear, Tow #, Sample ID, Net #, Depth Bin Category, Mesh Size (um), Swept Volume (m3), Plankton Displacement Vol (ml), Individual count (Total fish eggs, total fish larvae, B. Patronus).

Methods:

Plankton samples collected using a paired bongo (60 cm) fitted with 202 μm and 333 μm mesh. Bongo nets were towed just below the water surface for a duration of 10 minutes per tow. Mechanical flowmeters attached to the opening of each net were used to estimate the volume of water filtered. Zooplankton Processing: Plankton displacement volume was determined following the methods outlined in the ICES Zooplankton Methodology Manual (Harris et al., 2000). Samples greater with displacement volumes > 60 mL were further split to generate "sample aliquots", of which one was selected for further processing. The sample aliquot for sorting was poured into a 1000 mL graduated pitcher, and the volume was adjusted to a total of at least 200 mL but no more than 500 mL; this "count volume" was recorded. The aliquot was then stirred and aerated for 1 minute to ensure homogeneity. After aerating, an aliquot using a Stempel Pipet was taken and the "zooplankton aliquot" volume was recorded. The ideal aliquot should be enough to provide a count of at least 200 copepods and 200 of the other organisms combined, but small enough to prevent going over 500 for either. All organisms in the aliquot were counted ("taxon count"). The aliquot was then set aside for quality assurance/quality control by another taxonomist. From every set of 10 sample aliquot counts processed by an individual, one counted aliquot was randomly selected and recounted by someone other than the original taxonomist. The total number of each zooplankton taxon for each sample (the column values in the data set for each taxon) was then estimated using the following equation: Total number in sample = Taxon count x (Count Volume / Zooplankton Aliquot) x Sample Aliquot The density (number per cubic meter) of each taxon can then be derived by dividing the column values for each taxon by the swept volume.

Provenance and Historical References:

Harris, R., Wiebe, P., Lenz, J., Skjoldal, H. R., & Huntley, M. (Eds.). (2000). ICES zooplankton methodology manual. Elsevier.

Individual Files: