Fig. 1

Relative abundance of bacterial taxa on the kelp N. luetkeana. Sequences are grouped by phylum, class and genus-level taxonomy to show taxa detected by our CLASI-FISH probe set. 16S rRNA gene sequencing showed that bacterial composition was broadly consistent throughout the summer. The most abundant taxa were Gammaproteobacteria, Alphaproteobacteria, Bacteroidetes, and Verrucomicrobia. The gammaproteobacterial genus Granulosicoccus was highly abundant in samples from Tatoosh Island, while Alphaproteobacteria were dominant at Squaxin Island. Collection date is shown at the top, and collection site is shown at the bottom. Sample numbers and portion of the kelp blade sampled (T = tip; B = base; M = middle) are indicated in the x-axis labels