Size and isotopic ratios of macroinvertebrates in mangroves with and without seabirds

This dataset is used to investigate the trophic-response of mangrove invertebrate communities to nutrient subsidies supplied by seabird populations. It provides nitrogen (δ15N) and carbon (δ13C) isotopic composition of seabird guano, basal food sources (sediment, mangrove leaves, epiphytic macroalgae) and macroinvertebrate consumers (littornid gastropod, sesarmid crab, portunid crabs), as well as sizes of consumers, from mangroves with and without nesting seabirds. The data is used to determine the impacts of seabird-derived nutrients on mangrove macroinvertebrate sizes and resource contributions., This dataset was collected within the mangrove forests of Aldabra Atoll (Seychelles) between November 2022 and February 2023.
Details for each dataset are provided in the README file., , # Size and isotopic ratios of macroinvertebrates in mangroves with and without seabirds

[https://doi.org/10.5061/dryad.dncjsxm6m](https://doi.org/10.5061/dryad.dncjsxm6m)

The dataset contains the following raw data : Foodweb isotopic ratios (1 file), Gastropod size and isotopic ratios (1 file) and Crab size and isotopic ratios (1 file).

## Description of the data and file structure

Sample collection for this dataset occurred at 10 sites (5 seabird, 5 non-seabird sites) on Aldabra Atoll (Seychelles). Mangrove leaves, sediment, epiphytic macroalgae and gastropod samples were collected within 8 quadrats at each site (suffix A-H), while mangrove crabs were sampled randomly at the sites.

Raw data files:

1. Foodweb isotopic ratios:

foodweb_isotope.csv: isotope values of nitrogen (d15N) and carbon (d13C) and nitrogen (XN) and carbon (XC) of foodweb compartments - mangrove leaves, sediment, epiphytic macroalgae, littorinid gastropod (Littoraria spp.), sesarmid crab (Sesarma leptosoma)...