High-throughput sequencing of the 16S rRNA gene, microscopy, and flow cytometry of pyrosome-associated microorganisms compared to seawater sampled during a Pyrosoma atlanticum bloom in the Northern California Current System in July 2018.

Pyrosomes are widely distributed pelagic tunicates that have the potential to reshape marine food webs when they bloom. However, their grazing preferences and interactions with the background microbial community are poorly understood. The diversity, relative abundance, and taxonomy of pyrosome-associated microorganisms were compared to seawater during a Pyrosoma atlanticum bloom in the Northern California Current System using high-throughput sequencing of the 16S rRNA gene, microscopy, and flow cytometry.