Nanopore sequencing dataset of marine rocky shoreline microbial communities from the UK's first marine citizen science week event.

In March of 2025 the UK's first Marine Citizen Science Week recruited Citizen Scientists from around the country to participate in a series of activities exploring the ecology and biodiversity of rocky shorelines at sites on the northeast and southwest coastlines of England. To investigate the 'unseen' microbial biodiversity the organisers instructed participants to collect microorganisms from seawater using sterile pressure driven filtration units; these were sent to a laboratory for DNA extraction and metabarcoding analysis. DNA was extracted from material collected on the filter membranes and used in PCR amplification to generate 16S rRNA gene amplicons (bacterial) and 18S rRNA gene amplicons (protozoal). Each amplicon was ligated with a unique barcode and compiled into sequencing libraries, which were sequenced using Oxford Nanopore Technologies' MinION platform. The data sets for 16S rRNA gene amplicon sequencing and 18S rRNA gene amplicon sequencing reads have been uploaded as raw fastq files to the publicly accessible NCBI Sequencing Read Archive. The data sets provide an overview of the bacterial and eukaryotic microbial communities present in seawater collected from two geographically distinct rocky shore environments.