Burrowing crab effects across a tidal marsh successional chronosequence located along Mississippi sound

Burrowing crab engineers can affect the biological structure and sediment conditions of their environments. However, it is challenging to predict when and where burrow effects will manifest, as they are often site- and habitat-specific. We used a tidal marsh restoration chronosequence to explore crab burrow effects on plant communities (e.g., percent cover, biomass, stem heights) and sediment characteristics (e.g., bulk density, organic matter, carbon and nitrogen stocks) through early succession. In a field survey, we compared plants and sediments between plots with high and low crab burrow densities within three habitat zones: mud flat (i.e., 0-1 years old), young marsh (i.e., ~1-6 years old), and old marsh (i.e., ~6+ years old). In a manipulative experiment, we tested the physical effects of crab burrows on plants and sediments at the mud flat-young marsh ecotone using burrow mimics. In our field survey, crab burrow density did not influence plants or sediments. Rather, plant biomass..., Site description
To evaluate the relationship between burrowing crabs, plant communities, and sediment conditions along a successional gradient, we used a tidal salt marsh chronosqeunce at Greenwood Island, Pascagoula, Mississippi (hereafter, GWI; 0°20'00.5\"N 88°31'06.4\" W). Specifically, GWI is a restored tidal marsh originally constructed through the beneficial use of dredged sediments in 2007 and was expanded with additional dredge-material applications from 2015 through 2021 (Mississippi Department of Marine Resources personal communications). This process produced a chronosequence of relative tidal marsh age since restoration, with older vegetated marsh habitat (i.e., ~6+ years old; hereafter, old marsh), younger vegetated marsh habitat (i.e., ~1-6 years old; hereafter, young marsh), and unvegetated mud flats (i.e., <1 year old; hereafter, mud flat). The Mississippi Department of Marine Resources restored this tidal marsh via beneficial use of dredged sediments, which created a..., , # Burrowing crab effects across a tidal marsh successional chronosequence located along Mississippi sound.

[https://doi.org/10.5061/dryad.vhhmgqp3r](https://doi.org/10.5061/dryad.vhhmgqp3r)

## Description of the data and file structure

### Files and variables

#### File: Preliminary\_crab\_burrow\_desnisty\_across\_seasons.csv

**Description:** Data collected from the preliminary assessment of crab burrow densities across the three habitat types (i.e., mud flat, young marsh, old marsh) between March and November. 

##### Variables

* Zone: The habitat zone (i.e., mud flat, young marsh, old marsh) where the data was collected.
* Month: The month in which the data was collected from the permanent sampling plots. 
* Burrow density_1m2: The density of crab burrows scales up from 0.25m2 to 1m2.  

#### File: Experiment.csv

**Description:** Data collected from a manipulative field study looking at the physical effects of crab burrowing on the expansion and growth of *Spartina alterniflora...,