gov.noaa.nodc:0304846 eng utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NOAA Contact Information Information for contacts at NCEI. information custodian 2026-06-08T13:21:32Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) NOAA RESTORE Science Program: Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass (Thalassia testudinum): Nekton and primary producer stable isotopes in turtlegrass-dominated seagrass beds in the northern Gulf of America, 2018-05-23 to 2018-10-03 (NCEI Accession 0304846) 2025-06-24 publication 2025-06-03 creation International DOI Foundation (IDF) 10.25921/9b8j-zn57 NOAA National Centers for Environmental Information gov.noaa.nodc:0304846 NCEI Archive Management System 0304846 NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information publisher NOAA National Centers for Coastal Ocean Science (NCCOS) https://coastalscience.noaa.gov/ HTTPS NOAA National Centers for Coastal Ocean Science (NCCOS) website Institution web page information resourceProvider Kelly Darnell The University of Southern Mississippi (USM) kelly.darnell@usm.edu http://www.usm.edu/ HTTP The University of Southern Mississippi (USM) website Institution web page information principalInvestigator M. Zachary Darnell The University of Southern Mississippi (USM) zachary.darnell@usm.edu http://www.usm.edu/ HTTP The University of Southern Mississippi (USM) website Institution web page information principalInvestigator D. Lee Smee Dauphin Island Sea Lab (DISL) lsmee@disl.org https://www.disl.edu/ HTTPS Dauphin Island Sea Lab (DISL) website Institution web page information principalInvestigator Charles Martin University of Florida (UF) martin.charles.w@gmail.com http://www.ufl.edu/ HTTP University of Florida (UF) website Institution web page information principalInvestigator Margaret Hall Fish and Wildlife Research Institute (FWRI) penny.hall@myfwc.com http://myfwc.com/research/ HTTP Fish and Wildlife Research Institute (FWRI) website Institution web page information principalInvestigator Bradley Furman Fish and Wildlife Research Institute (FWRI) Bradley.furman@myfwc.com http://myfwc.com/research/ HTTP Fish and Wildlife Research Institute (FWRI) website Institution web page information principalInvestigator Kelly Darnell The University of Southern Mississippi (USM) Kelly.darnell@usm.edu http://www.usm.edu/ HTTP The University of Southern Mississippi (USM) website Institution web page information pointOfContact Frank Parker NOAA RESTORE Science Program frank.parker@noaa.gov https://restoreactscienceprogram.noaa.gov/ HTTPS NOAA RESTORE Science Program website Institution web page information pointOfContact NOAA National Centers for Coastal Ocean Science (NCCOS) NCCOS Data Manager nccos.data@noaa.gov https://coastalscience.noaa.gov/ HTTPS NOAA National Centers for Coastal Ocean Science (NCCOS) website Institution web page information pointOfContact NOAA RESTORE Science Program noaarestorescience@noaa.gov https://restoreactscienceprogram.noaa.gov/ HTTPS NOAA RESTORE Science Program website Institution web page information pointOfContact Darnell, Kelly M. The University of Southern Mississippi (USM) http://www.usm.edu/ HTTP The University of Southern Mississippi (USM) website Institution web page information author Darnell, M. Zachary The University of Southern Mississippi (USM) http://www.usm.edu/ HTTP The University of Southern Mississippi (USM) website Institution web page information author Smee, D. Lee Dauphin Island Sea Lab (DISL) https://www.disl.edu/ HTTPS Dauphin Island Sea Lab (DISL) website Institution web page information author Martin, Charles W. University of Florida (UF) http://www.ufl.edu/ HTTP University of Florida (UF) website Institution web page information author Hall, Margaret O. Fish and Wildlife Research Institute (FWRI) http://myfwc.com/research/ HTTP Fish and Wildlife Research Institute (FWRI) website Institution web page information author Furman, Bradley Fish and Wildlife Research Institute (FWRI) http://myfwc.com/research/ HTTP Fish and Wildlife Research Institute (FWRI) website Institution web page information author Dauphin Island Sea Lab (DISL) https://www.disl.edu/ HTTPS Dauphin Island Sea Lab (DISL) website Institution web page information contributor NOAA National Centers for Coastal Ocean Science (NCCOS) https://coastalscience.noaa.gov/ HTTPS NOAA National Centers for Coastal Ocean Science (NCCOS) website Institution web page information contributor The University of Southern Mississippi (USM) http://www.usm.edu/ HTTP The University of Southern Mississippi (USM) website Institution web page information contributor Fish and Wildlife Research Institute (FWRI) http://myfwc.com/research/ HTTP Fish and Wildlife Research Institute (FWRI) website Institution web page information contributor University of Florida (UF) http://www.ufl.edu/ HTTP University of Florida (UF) website Institution web page information contributor NOAA RESTORE Science Program https://restoreactscienceprogram.noaa.gov/ HTTPS NOAA RESTORE Science Program website Institution web page information contributor tableDigital This dataset consists of stable isotope data from turtlegrass-dominated seagrass beds of the northern Gulf of America (formally the Gulf of Mexico), including Lower Laguna Madre, TX; Coastal Bend, TX; Chandeleur Islands, LA; St. George Sound, FL; Cedar Key, FL, and Charlotte Harbor, FL. Data are in spreadsheet format. The overarching goal of this project is to conduct a management-driven, Gulf of America (formerly Gulf of Mexico)-wide assessment of the use of turtlegrass as habitat by nekton and to evaluate the support provided to blue crabs, a commercially valuable species, using habitat-specific production estimates. This project was a collaboration between The University of Southern Mississippi, Dauphin Island Sea Lab, University of Florida, and Florida Fish and Wildlife Research Institute. Funding Agency: NOAA RESTORE Science Program Award Number: NA17NOS4510093 to the University of Southern Mississippi Funding Agency: NOAA RESTORE Science Program Partner: The University of Southern Mississippi Partner: Dauphin Island Sea Lab Partner: University of South Alabama Partner: University of Florida Partner: Florida Fish and Wildlife Research Institute completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information pointOfContact asNeeded https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0304846 Preview graphic PNG 0304846 NCEI ACCESSION NUMBER 2025-05-21 publication biological data CARBON LATITUDE LONGITUDE MACROALGAE NITROGEN SEA GRASSES - DENSITY SPECIES IDENTIFICATION SPECIES IDENTIFICATION - ORGANISM LENGTH SUBSTRATE DESCRIPTION suspended solids theme NODC DATA TYPES THESAURUS mass spectrometer trawl instrument NODC INSTRUMENT TYPES THESAURUS biological in situ laboratory analyses survey - biological theme NODC OBSERVATION TYPES THESAURUS Dauphin Island Sea Lab Fish and Wildlife Research Institute NOAA National Centers for Coastal Ocean Science NOAA RESTORE Science Program The University of Southern Mississippi University of Florida dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS NOAA National Centers for Coastal Ocean Science dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS Coastal Waters of Florida Coastal Waters of Gulf of America Coastal Waters of Gulf of Mexico Coastal Waters of Louisiana Coastal Waters of Texas place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication DOC/NOAA/NOS/NCCOS > National Centers for Coastal Ocean Science, National Ocean Service, NOAA, U.S. Department of Commerce dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian NOAA RESTORE Science Program (NA17NOS4510093) NOAA RESTORE Science Program: Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass (Thalassia testudinum) US DOC; NOAA; NOS; NCCOS; RESTORE Science Program (ROR - https://ror.org/0042xzm63) project Provider Project Names EARTH SCIENCE > BIOLOGICAL CLASSIFICATION EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > PLANTS > ANGIOSPERMS (FLOWERING PLANTS) > MONOCOTS > SEAGRASS EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > PLANTS > MACROALGAE (SEAWEEDS) EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > CARBON EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > NITROGEN EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > SUSPENDED SOLIDS theme Global Change Master Directory (GCMD) Science Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian NCCOS Research Data Type > Field Observation theme NCCOS Research Data Type NCCOS Research Topic > Ecological and Biogeographic Assessments theme NCCOS Research Topic nekton primary producer stable isotopes turtlegrass theme Provider Keywords MASS SPECTROMETERS > MASS SPECTROMETERS TRAWL instrument Global Change Master Directory (GCMD) Instrument Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian 4.8 m flat trawl Thermo-Fisher Scientific Delta V Advantage Isotope Ratio Mass Spectrometer epibenthic sled instrument Provider Instruments OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF AMERICA OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF MEXICO place Global Change Master Directory (GCMD) Location Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian NCCOS Research Location > Region > Gulf of America (formerly Gulf of Mexico) place NCCOS Research Location Apalachicola, FL Breton National Wildlife Refuge Cedar Key, FL Chandeleur Sound, Louisiana Charlotte Harbor, Florida Coastal Bend, TX Laguna Madre, Texas NCCOS Research Location > Region > Gulf of America Redfish Bay, Texas St. George Sound, Florida place Provider Place Names 83WX8P Send2NCEI Submission Package ID accessLevel: public otherRestrictions Cite as: Darnell, Kelly M.; Darnell, M. Zachary; Smee, D. Lee; Martin, Charles W.; Hall, Margaret O.; Furman, Bradley (2025). NOAA RESTORE Science Program: Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass (Thalassia testudinum): Nekton and primary producer stable isotopes in turtlegrass-dominated seagrass beds in the northern Gulf of America, 2018-05-23 to 2018-10-03 (NCEI Accession 0304846). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/9b8j-zn57. Accessed [date]. Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose. license This dataset has been dedicated to the public domain under the Creative Commons CC0 1.0 Universal (CC0 1.0) Public Domain Dedication. SPDX License: Creative Commons Zero v1.0 Universal (CC0-1.0) Levin LA, Currin C (2012) Stable isotope protocols: sampling and sample processing. Scripps Institution of Oceanography, University of California, San Diego, https://escholarship.org/uc/item/3jw2v1hh 2012 publication https://escholarship.org/uc/item/3jw2v1hh HTTPS https://escholarship.org/uc/item/3jw2v1hh Sample Processing Journal Article information Levin, Lisa A author Currin, Carolyn author Scripps Institution of Oceanography publisher crossReference Olsen, Z., Fulford, R., Dillon, K., & Graham, W. (2014). Trophic role of gulf menhaden Brevoortia patronus examined with carbon and nitrogen stable isotope analysis. Marine Ecology Progress Series, 497, 215–227. https://doi.org/10.3354/meps10519 2014-02-05 publication International DOI Foundation (IDF) https://doi.org/10.3354/meps10519 https://doi.org/10.3354/meps10519 HTTPS https://doi.org/10.3354/meps10519 Journal Article information Olsen, Z author Fulford, R author Dillon, K author Graham, W author Inter-Research Science Center publisher documentDigital Mar. Ecol. Prog. Ser. 497 ISSN 0171-8630, ISSN 1616-1599, pp. 215-227 crossReference National Centers for Coastal Ocean Science. 2020. RESTORE Sponsored Research Project: Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass (Thalassia testudinum). https://inport.nmfs.noaa.gov/inport/item/66730 2020 publication https://www.fisheries.noaa.gov/inport/item/66730 HTTPS https://www.fisheries.noaa.gov/inport/item/66730 Inport Metadata Webpage information National Centers for Coastal Ocean Science author National Centers for Coastal Ocean Science publisher crossReference RESTORE Project, Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass (Thalassia testudinum) https://restoreactscienceprogram.noaa.gov/projects/turtlegrass 2022 publication https://restoreactscienceprogram.noaa.gov/projects/turtlegrass HTTPS https://restoreactscienceprogram.noaa.gov/projects/turtlegrass NOAA RESTORE Science Program Project Webpage information crossReference The University of Southern Mississippi: Coastal Ecology and Seagrass Biology Lab. Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass (Thalassia testudinum). https://www.darnellseagrassecologylab.com/turtlegrass 2022 publication https://www.darnellseagrassecologylab.com/turtlegrass HTTPS https://www.darnellseagrassecologylab.com/turtlegrass Lab Project Page information crossReference eng; USA utf8 environment oceans biota -97.2812 -82.0594 26.0819 29.98204 2018-05-23 2018-10-03 Methods: Sample Collection Nekton and primary producer sources were collected from May23–October 3, 2018 at six sites spanning the range of turtlegrass distribution in the Northern GOM. Two sites were located in Texas (Lower Laguna Madre [LM] and the Texas Coastal Bend [CB]), one site in Louisiana (Chandeleur Islands [LA]), and three sites in Florida, (St. George Sound [AP], Cedar Key [CK], and Charlotte Harbor [CH]). Sampling stations at each of the six sites were chosen using a stratified random sampling method of hexagonal tessellation in which a grid of hexagons (500 or 750 m edge) was overlaid on the mapped areal extent of known turtlegrass cover at each site, and 25 hexagons with > 50% turtlegrass cover were randomly selected to conduct surveys. In cases where no turtlegrass was found at a station, or stations were inaccessible, alternative hexagons were chosen and new stations were randomly generated. Mean distance between the farthest sampling stations at each site was 22.5 ± 2.4 km (Laguna Madre, TX = 20 km, Coastal Bend, TX = 20 km, Chandeleur Islands, LA = 24 km, Saint George Sound, FL = 21 km, Cedar Key, FL = 25 km, and Charlotte Harbor = 25 km). All animal and vegetation samples were collected as part of a survey to assess nekton habitat use in turtlegrass environments. Larger nekton and drift macroalgae samples were collected at each site using a 4.8 m flat trawl towed from a boat for 2–3 minutes at a speed of 3.7–5.6 km min-1, and smaller nekton and additional macroalgae samples were collected using an 0.75 m wide epibenthic sled pulled by hand a distance of 13.3 m at a speed of ~0.3 m s-1. All individuals were measured for standard length (SL) and total length (TL) (carapace width, CW, for crabs) prior to processing to account for changes in δ15N values related to diet changes with size, and were identified to the lowest practical taxonomic level. Because of logistical difficulties in identifying different macroalgae species, macroalgae samples were identified based on functional traits and major taxa grouping (e.g., Rhodophyta, red branching macroalgae). At each site, trawl and epibenthic sled surveys were conducted on different days to prevent disturbance to the habitat. Approximately five individuals of each species collected at each site were retained for analysis. Vascular plant samples of all seagrass species and adjacent marsh species were collected by hand at a subset of five stations across each site. All epiphytes present on macrophyte leaves were removed by gently scraping with a razor blade and macroalgae samples were picked free of visible meiofauna and detritus to avoid isotopic signature contamination. Benthic microalgae (BMA) were collected at a subset of five stations at each site using a glass plate collector methodology (Dillon et al. 2015), in which paired collector plates were partially pushed in the sediment at each station, retrieved after one week, rinsed to remove sediment, separated, and scraped to collect microalgae. Suspended particulate organic matter (POM) samples were collected at five representative stations at each site using 60 mL plastic syringes with 2.5 cm glass fiber filters. All nekton and primary producer samples were transported on ice and frozen at the Gulf Coast Research Lab, The University of Southern Mississippi prior to isotopic analysis. A subset of 30 common nekton taxa representing multiple tropic levels, feeding strategies, and ecological niches were collected and used for stable isotope analyses, including five seagrass species ( turtlegrass, shoal grass, manatee grass, widgeon grass, and star grass), two mangrove species (Avicennia germinans and Rhizophora mangle), two C3 marsh plant species (Phragmites sp. and Juncus roemerianus), two C4 marsh plant species (Sporobolus alterniflorus and Sporobolus pumilus), 20 macroalgae groups, POM samples, and BMA samples. Small invertebrates, primary producers, fish, and POM samples were processed whole, whereas subsamples of muscle tissue were taken from larger fish and invertebrates such as pinfish (Lagodon rhomboides), pigfish (Orthopristis chrysoptera), and inshore lizardfish (Synodus foetens). Smaller individuals for some taxa (e.g., Hippolytid shrimp) within a single collection at each station were combined to achieve enough mass for isotopic analysis. Nekton and primary producer samples were rinsed with deionized (DI) water to remove sediment, dried to a constant weight at 60°C using a drying oven, then ground to a fine powder using either a mortar and pestle or a Wiley mill equipped with a #20 or #40 mesh delivery tube. Samples were stored in clean scintillation vials in desiccators prior to analysis and POM samples were acid fumed for 24 hrs using concentrated hydrochloric acid (HCl) to remove inorganic carbonates. All macroalgae taxa were rinsed once with 10% HCl and three times with DI water to remove inorganic carbonates. After each DI water rinse, samples were shaken vigorously using a Vortex mixer (GENIE SI-0235, Scientific Industries), centrifuged, and decanted. Following the final rinsing, acid washed samples were dried in a drying at 60°C for 24 hrs. Acid-washed portions of macroalgae samples were used for carbon isotope analysis and unwashed portions were used for nitrogen analysis because acid washing is known to bias δ15N values (Pinnegar & Polunin 1999). Samples were packed into tin capsules and analyzed for δ13C and δ15N signatures following standardized protocols (Levin & Currin 2012, Olsen et al. 2014) using continuous-flow stable isotope ratio mass spectrometry (CF-IRMS) with a Costech 93 Elemental Combustion System coupled to a Thermo-Fisher Scientific Delta V Advantage Isotope Ratio Mass Spectrometer at the Gulf Coast Research Lab Stable Isotope Facility. Most (95%) nekton and primary producer samples were analyzed in duplicate, aside from some samples with limited material and POM samples, which were analyzed as single samples (5%). Carbon and nitrogen stable isotope values were calculated according to the formula δX=[(𝑅𝑠𝑎𝑚𝑝𝑙𝑒/Rstandard )−1]×103 where X is 13C or 15N and R is the ratio of heavy to light isotopes (13C/12C or 15N/14N) for the samples or the standard (PeeDee belemnite [PDB] carbon or atmospheric dinitrogen [N2]). NOAA National Centers for Environmental Information +1-301-713-3277 ncei.info@noaa.gov pointOfContact In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. Excel PDF 3.664 https://doi.org/10.25921/9b8j-zn57 HTTPS Web browser NCEI Dataset Landing Page Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/oas/304846 HTTPS Web browser Descriptive Information Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/download/304846 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0231/0304846/ FTP Any FTP client FTP These data are available through the File Transfer Protocol (FTP). FTP is no longer supported by most internet browsers. You may copy and paste the FTP link to the data into an FTP client (e.g., FileZilla or WinSCP). download dataset NCEI Accession 0304846 v1.1 was published. 2025-06-24T15:44:34Z NCEI Accession 0304846 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0304846/1.1 HTTPS NCEI Accession 0304846 v1.1 published 2025-06-24T15:44:34Z download dataset Parameter or Variable: stable isotopes (measured); Units: see methods; Observation Category: laboratory analysis; Sampling Instrument: Thermo-Fisher Scientific Delta V Advantage Isotope Ratio Mass Spectrometer; Sampling and Analyzing Method: See methods section Parameter or Variable: Nekton and primary producer (measured); Units: n/a; Observation Category: in situ; Sampling Instrument: 4.8 m flat trawl and epibenthic sled; Sampling and Analyzing Method: see methods section Parameter or Variable: turtlegrass (measured); Units: n/a; Observation Category: in situ; Sampling Instrument: n/a asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian mass spectrometer mass spectrometer Instrument that measure the massess and relative concentrations of atoms and molecules trawl trawl A fishing net that is dragged behind a boat. A wide range of demersal (bottom) or pelagic (mid-water) species of fish are taken by this fishing method which entails one or a pair of vessels towing a large bag-shaped net either along the seafloor or in mid-water.