A guest post from Julia Stevens, who we are collaborating with on a new lionfish project….
Lionfish have a close relationship with the bacteria living on their skin. Some of these bacteria, seemingly acquired from the environment, are part of a core microbiome that contains similar taxa in both the invaded and native ranges of the lionfish. Overall, the lionfish microbiome is different than those of native Atlantic fishes, including squirrelfish, and contain beneficial, antibacterial taxa. Bacteria sequenced from water samples collected throughout both ranges showed a highly dissimilar bacterial assemblage compared to those on lionfish external surfaces. To explore the possible source of this lionfish core bacterial community, we are now comparing the effects habitat type and structure on lionfish bacteria. Using artificial reef systems built 7 years ago, we collected lionfish and squirrelfish samples corresponding to water and reef surface samples.
This project seeks to address two questions: What is the source of the lionfish core bacteria? Do artificial reefs change host-microbe dynamics relative to natural reefs? In other words, if lionfish develop their core microbiome from surface contact, we want to determine if this transfer can happen from artificial structures. Preliminary results indicate the reef type (artificial vs. natural) has a significant effect on both lionfish and squirrelfish skin bacteria. And, while squirrelfish bacterial communities were more similar to the ambient bacterioplankton (free bacteria in the water column), lionfish bacteria more closely resembled the bacteria present on the reef surface. Currently we are expanding this project to include other fish species common to both the natural and artificial reefs and will conduct a source tracking analysis for the fish-associated bacteria.