An environmental microbiome study of Loch Ryan: Taxonomic and abundance data

The microbiome plays a key role in animal health and is an important aspect of any natural or farmed ecosystem. Here we present the first environmental microbiome study of Ostrea edulis, as well as the first of a natural wild spawning event of any oyster species. Larval abundance was hypothesised to be correlated with specific microbial signatures. Water samples were collected throughout a natural spawning event of O. edulis at Loch Ryan, Scotland, UK. Samples were collected on 4 different dates from June to September 2019, across 8 different sampling sites on the Loch at mid, bottom, and surface levels within the water column to remove the effects of salinity and tidal fluctuations. Larval count data was obtained from these samples before full-length sequencing of the 16S rRNA gene using Oxford Nanopore Technologies. Significant microbial differences were only found between samples collected on different dates, and not at different sites or water column depths. Differences in the micro..., Sample collection: 
Weekly water samples were collected from Loch Ryan between the 7th June to 24th September 2019 as described by Chapman et al, (2021). This sampling time frame was chosen to cover the native oyster spawning season as comprehensively as possible. Water samples were collected across 8 different sites in the Loch, covering 4 sites from known oyster fishing grounds off Lefnoll Point, and 4 sites from non-oyster bed habitats (see Figure 1a, Chapman et al, 2021). The location of all sample sites visited on Loch Ryan in relation to the oyster beds can be seen in Figure 1. Water was collected from the surface, mid and bottom points within the water column using the pump and trap method (see Fig.2. Chapman et al, 2021). Each sample was filtered through a 90µm mesh to capture plankton (but retain oyster larvae) within the water with 200 L of filtrate being measured from each sample. All samples were then used to conduct larval counts of both O. edulis and other bivalves such as..., , # An environmental microbiome study of Loch Ryan: Taxonomic and abundance data

[https://doi.org/10.5061/dryad.83bk3jb1s](https://doi.org/10.5061/dryad.83bk3jb1s)

##### Description of the data and file structure

The data linked here consists of one Excel sheet, containing three sheets:

**Sheet 1**: An OTU (Organised Taxonomic Unit) table, listing the abundance numbers of each OTU within each sample. OTU's are listed in rows against individual samples in columns. The heading of each column contains the barcode number used during the metabarcoding of that sample. A total of 995 OTU's were identified. 

**Sheet 2**: A list identifying each OTU at different taxonomic levels. Most OTU's were identified down to a genus level. Where a genus level of identification was not possible, 'Unknown Genus' is seen under the 'Genus' heading for that OTU. A total of 995 OTU's are listed (matching the abundance data shown on sheet 1). 

**Sheet 3**: Metadata giving information on each water sample incl...