Abstract:

A series of Natural Resource Damage Assessment (NRDA) cruises were conducted in 2010 and 2011 to evaluate the distribution and densities of ichthyoplankton and other zooplankton in Gulf of Mexico waters potentially affected by the Deepwater Horizon Oil Spill (DWHOS) and in surrounding areas. This dataset includes larval fish (family: Paralepididae) diet and stable isotope data from samples collected on NRDA plankton and NRDA Nekton surveys, 2010-2011. It includes data for ichthyoplankton specimens (taxonomic identification, length, weight, stable carbon and nitrogen values, compound specific amino acid values) and their corresponding diets (prey taxonomic identification, number of individuals, length, weight).

Suggested Citation:

Gipson, Emily, Verena Wang, Carley Zapfe, Kevin Dillon, and Frank Hernandez. 2021. Diet and stable isotope (bulk-tissue and compound specific amino acid) data of larval and juvenile deep pelagic Paralepidid fishes collected in the northern Gulf of Mexico during the Deepwater Horizon (DWH) Natural Resource Damage Assessment (NRDA). Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/W39GXEG1

Purpose:

The purpose of the dataset is to describe diets and trophic linkages for dominant, deep-pelagic larval and juvenile fishes. Data collection methods included gut content analysis, bulk-tissue stable isotope analysis, and compound-specific isotope analysis of amino acids. When combined with trophic data for adult stages, these results will help us understand the ecological role of deep-pelagic fishes and their larvae in connecting the epipelagic with the deep ocean. Ultimately the data will also inform the vertically resolved ecosystem model being developed for this project. The data presented here are a portion of work completed by Emily Gipson (author) as part of her master's thesis requirements.

Data Parameters and Units:

The dataset contains one Excel file (ReadMe) and three separate CSV files with Gut Content Data; Bulk SI Results; and CSIA Results. Gut Content Data: Fish Sample ID [The full sample ID for each individual fish specimen (Hernandez number + Fish ID for plankton; NRDA Sample ID + Fish ID for nekton)]; NRDA Sample ID [Unique identifier for each depth discrete net sample assigned during Deep Water Horizon Natural Resource Damage Assessment sample processing]; Hernandez number [Unique identifier used by the processing laboratory using the number assigned to the sample in the Deepwater Horizon Plankton Assessment Archive (DWHPAA). Number is listed as NA for samples housed by the DWHPAA but not accessioned (nekton)]; Fish ID [Identifier assigned to each specimen removed from the same sample vial for analysis (Taxon - n); not unique among vials]; Taxon [Lowest taxonomic identification]; Cruise Name [Survey vessel]; Cruise No [Number of NRDA survey on above vessel]; Sample Date [Date sample was collected]; Station ID [Station name (B# stations are from the NOAA SEAMAP Grid)]; Latitude [Target station latitude]; Longitude [Target station longitude]; Upper Depth [Minimum depth sampled by net (m)]; Lower Depth [Maximum depth sampled by net (m)]; Life Stage [Developmental stage]; Mag [Microscope magnification at the time of length measurement]; SL [Standard length (mm)]; CSIA [Compound specific isotope analysis conducted (Y- Yes, N- No)]; Bulk SI [Bulk tissue stable isotope analysis conducted (Y- Yes, N- No)]; Gut Intact [Whole gut tract intact at the time of removal (Y- Yes, N- No)]; Gut Fullness [Amount of contents found in gut; on a scale of 0-3 with 0 being empty and 3 being 90% full or greater]; Date counted [Date the gut was removed and contents identified]; Teleost [Gut contents - number of teleost fish present]; Cladoceran [Gut contents -number of cladocerans present]; Poecilostomatoid Copepod [Gut contents - number of Poecilostomatoid copepods present]; General Copepod [Gut contents - number of general (unidentifiable) copepods present]; Invert Egg [Gut contents - number of invertebrate eggs present]; Mouth Contents Present [Prey items detected in mouth cavity, but not included in gut content counts (Y- Yes, N- No)]. Bulk SI Results: Combined Fish ID [Fish specimen ID (or combined fish ID where necessary, see 'Bulk SI Sample ID Key' for combined fish details); 'Gut Contents' indicates stable isotope analysis of gut contents from fish specimen]; 13C [Stable carbon isotopic ratio (δ13C)]; 15N [Stable nitrogen isotopic ratio (δ15N)]; Total fish [Total number of fish in final Combined Fish ID sample, NA if gut contents from a fish specimen were analyzed]; Fish Sample ID 1-10 [Fish Sample ID 1-10; see 'Gut Content Data' for additional information on each specimen; if a single fish was used in the sample, Combined Fish ID is identical to Fish Sample ID #. NA if gut contents from a fish specimen (identified in Combined Fish ID) were analyzed]. CSIA Results: USM ID [Unique identifier for CSIA analysis; See 'CSIA Sample ID Key' for list of individual fish combined in each USM ID]; Alanine [Amino acid stable nitrogen isotopic composition (δ15N)]; Aspartic Acid [Amino acid stable nitrogen isotopic composition (δ15N)]; Glutamic Acid [Amino acid stable nitrogen isotopic composition (δ15N)]; Glycine Amino acid stable nitrogen isotopic composition (δ15N)]; Isoleucine [Amino acid stable nitrogen isotopic composition (δ15N)]; Leucine [Amino acid stable nitrogen isotopic composition (δ15N)]; Lysine [Amino acid stable nitrogen isotopic composition (δ15N)]; Methionine [Amino acid stable nitrogen isotopic composition (δ15N)]; Phenylalanine [Amino acid stable nitrogen isotopic composition (δ15N)]; Proline [Amino acid stable nitrogen isotopic composition (δ15N)]; Serine [Amino acid stable nitrogen isotopic composition (δ15N)]; Threonine [Amino acid stable nitrogen isotopic composition (δ15N)]; Valine [Amino acid stable nitrogen isotopic composition (δ15N)]; USM ID [Unique identifier assigned to the samples for CSIA analysis]; Genus; Spp [Species]; Combined Sample ID [Unique sample ID after fish combination (noted with a 'c'); when sample combination was not required, Combined Sample ID is equivalent to Fish Sample ID 1]; Total fish [Total number of fish in final USM ID sample]; and Fish Sample ID 1-5 [Fish Sample ID 1-5; see 'Gut Content Data' for additional information on each specimen]. Note: Please note that the blank cells [M124 and S19] in the file "Paralepididae Gut Content Data.csv" means "no data were recorded".

Methods:

Fish specimens from the family Paralepididae were selected for trophic analysis based on sampling depth, geographic location, and specimen size (to meet minimum sample requirements for SI analysis). When possible, specimens identified to the family level during the NRDA process were further identified to species by Emily Gipson (USM) and Lauren Jackson (NOAA, NCEI). Guts were removed from specimens while minimizing damage to the fish and the gut. Stomach contents were identified to the lowest taxonomic resolution, and intact prey was measured. Fish were transferred from 85% EtOH to deionized water, with water changes conducted every 24 hours for 2 days to remove residual preservatives. Fish were dried at 60 °C for 24 hrs, and dried fish were ground to powder and were weighed to targeted amounts (1.5 mg for compound-specific isotope analysis (CSIA) analysis, 0.3 mg - 0.5mg for bulk stable isotope analysis). When necessary, multiple small fish from the same taxa, location, and depth were combined to reach the required amount of material. Fish for CSIA was sent to the University of California Davis Isotope Facility. Fish for bulk stable isotope analysis were packed into 5 x 9 mm Costech tin capsules. Any remaining ground tissue was archived for future analysis. Compound specific isotope analysis of amino acids was conducted by the University of California Davis Stable Isotope Facility. Bulk tissue stable isotope analysis was conducted at the University of Southern Mississippi Marine Ecosystems Research Laboratory. Samples were analyzed for stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) using a Thermo Delta V stable isotope ratio mass spectrometer coupled to a Costech 4010 elemental analyzer by a Thermo Confo IV continuous flow interface. Isotopic values were calculated relative to conventional standards for each element of interest and expressed in standard delta (δ) notation.

Instruments:

Plankton cruises (Walton Smith 1, Walton Smith 3, Walton Smith 4, Nick Skansi 9) - 1-m^2 Multiple Opening/Closing Net Environmental Sensing System (MOCNESS) outfitted with nine 0.333mm nets; Nekton cruises (Meg Skansi 6, Meg Skansi 7, Meg Skansi 8) - 10-m^2 Multiple Opening/Closing Net Environmental Sensing System (MOCNESS) outfitted with nine 3.00 mm nets; Thermo Delta V stable isotope ratio mass spectrometer coupled to a Costech 4010 elemental analyzer via a Thermo Confo IV continuous flow interface; Mettler-Toledo MicroAnalytical Balance.

Provenance and Historical References:

Specimens provided in this dataset are generated from the Natural Resource Damage Assessment Deepwater Horizon Oil Spill Plankton Processing Plan and the Deepwater Horizon Oil Spill Nekton Processing Plan. Stations sampled are on the Southeast Area Monitoring and Assessment Program (SEAMAP) Gulf of Mexico grid.

Individual Files: