Dataset DOI: 10.5061/dryad.d7wm37qcd

Description of the data and file structure

A stable isotope dataset was developed from literature sources for this study with taxa comprising functional groupings of the De Mutsert et al. (2017) Ecopath with Ecosim (EwE) model and additional taxa representing terrestrial and aquatic food web baselines. It contains 3,465 data points from 50 species located in Barataria Bay, Louisiana (LA), aggregated from 13 sources dating from 2001 – 2018. The majority of the data sources (11) and associated data points (2,979) provided carbon and nitrogen stable isotope values at the individual sample level. However, two data sources contained only the mean and standard deviations of carbon and nitrogen stable isotope values, and the number of individuals measured. Following the methods of James et al. (2020), individual level data points were randomly generated from the mean and standard deviation of each taxa assuming a normal distribution, resulting in 486 data points. The dataset was then organized to reflect 47 of the functional groupings used in the De Mutsert et al. (2017) model. Functional grouping includes those that are split into age classes (juvenile or adult) following De Mutsert et al. (2017) models. Where size (i.e., length) information was reported in the original data sources, we compared reported values to literature derived length at maturity equations to sort each individual into a particular age class (juvenile or adult) for specific functional groupings corresponding to the De Mutsert et al. (2017) model.  An additional data column was added to denote taxa used as terrestrial (i.e., herbivorous insects) and aquatic (e.g., mussels and barnacles) for the estimation of trophic position using stable isotope values. Please note that the data and code underlying the De Mutsert et al. (2017) Mississippi River Delta model are publicly available via the EcoBase repository at https://ecobase.ecopath.org/#discoverytools. 

Citations:

• de Mutsert, K., Lewis, K., Milroy, S., Buszowski, J., & Steenbeek, J. (2017). Using ecosystem modeling to evaluate trade-offs in coastal management: effects of large-scale river diversions on fish and fisheries. Ecological Modelling, 360, 14-26.
• James, W. R., Lesser, J. S., Litvin, S. Y., & Nelson, J. A. (2020). Assessment of food web recovery following restoration using resource niche metrics. Science of the Total Environment, 711, 134801.

Files and variables

File: Lewis_et_al._Dryad_Data_6-30-2026.xlsx

Description: The data is organized into one Excel file with three sheets. The first sheet “Data” contains the 3,828 data points. The second sheet “SIA_Source” provides the citation information for the 13 data sources from which carbon and nitrogen stable isotope values were extracted. The third sheet “Age_Source” provides the citation information for the 40 literature sources which were used to obtain length at maturity equations to categorize the age classes (juvenile or adult) of individuals. Definitions of dataset terms are found in the table below using the “Variables: Description | Units” format. “NA” in a cell indicates not applicable (Variables: Other_ID_1, Other_ID_2, Age_Group, EwE_Node, Age_Source)  and/or not available (Variables: d13C, d15N, CN_ratio) data. Contact polito@ucsc.edu if questions.

First sheet: “Data”

Variables

• Sample_ID: Individual sample code | None
•  Other_ID_1: Second individual sample code if available | None
• Other_ID_2: Third individual sample code if available | None
• Date: The verbatim collection date of each sample in Month YYYY format, Month YYYY range format, or if specific dates were available in the MM/DD/YYYY format | None
• Date: The collection year or year range in YYYY format | None
• State: Name of the state (Louisiana) where sample was collected | None
• Region: Name of the region where sample was collected | None
• Area: Name of the location where sample was collected | None
• Site: Name of site where sample was collected | None
• Latitude: Sample collection latitude | Decimal degrees
• Longitude: Sample collection longitude | Decimal degrees
• Taxa: The specific scientific or taxonomic name | None
• Common_name: The common taxonomic name | None
• n: The number of individuals used to create the sample | None
• Size_mm: The individual size of the organism if reported| mm
• Size_Method: The size method used (TL = total length, FL = fork length, SL = Standard length, CW = carapace width, SLC = Straight Carapace Length) | None
• Age_Group: The age classes (juvenile or adult) of individuals based on literature derived length at maturity equations | None
• EwE_Node: The corresponding functional groupings as defined by the De Mutsert et al. (2017) Ecopath with Ecosim (EwE) model | None
• FG: The corresponding functional groupings as defined by the De Mutsert et al. (2017) Ecopath with Ecosim (EwE) model as well as referring samples used as aquatic or terrestrial baselines for trophic position calculations | None
• Tissue: The tissue type analyzed | None
• d13C: Carbon (C) isotopic value in sample expressed in the delta (δ) notation | ‰
• d15N: Nitrogen (N) isotopic value in sample expressed in the delta (δ) notation | ‰
• CN_ratio: Carbon (C) to nitrogen (N) elemental ratio in sample if known | None
• Data_Type: Denotes if individual sample level data was extracted from the data source (Individual), individual level carbon and nitrogen stable isotope values were randomly generated from the means, standard deviations, and samples sizes reported the data source (Generated) | None
• SIA_Source: The citation ID for the data sources from which carbon and nitrogen stable isotope values were extracted | None
• AGE_Source: The citation ID for the data sources from which length at maturity equations were extracted | None
• Notes: Additional notes about samples as relevant | None

Second sheet: “SIA_Source”

Variables

• Source_ID: The citation ID for the data sources from which carbon and nitrogen stable isotope values were extracted | None
• Citation: The citation for the data sources from which carbon and nitrogen stable isotope values were extracted | None
• DOI_URL: The DOI or URL of the data sources from which carbon and nitrogen stable isotope values were extracted | None
• Notes: Additional notes about data sources as relevant | None

Third sheet: “Age_Source”

Variables

• Source_ID: The citation ID for the data sources from which length at maturity equations were extracted | None
• Citation: The citation for the data sources from which length at maturity equations were extracted | None
• DOI_URL: The DOI or URL of the data sources from which length at maturity equations were extracted | None
• Notes: Additional notes about data sources as relevant | None

Access information

Data was derived from the following sources:

• This database reflects a subset of a larger dataset compiled by: 
  • Polito, Michael J., Sydney Moyo, Linda Hooper-Bui, Emma Morgan, and Kristy A. Lewis. 2025. Literature review of carbon and nitrogen stable isotope values from taxa collected from various habitats within and around Barataria Bay, Louisiana from 2001-2019. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. https://doi.org/10.7266/TE8TATHR
• See "SIA_Source" sheet in attached Excel file for individual data sources related to each sample.