Influence of developmental stage, habitat, and captivity on thecutaneous bacterial communities of Eastern Hellbenders (Cryptobranchus Alleganiensis Alleganiensis) in West Virginia

Microbes inhabit virtually all surfaces of multicellular animal hosts, with microbial cells outnumbering the hosts’ own cells 10:1. Symbiont microbes, collectively referred to as the microbiome, can have profound impacts on the metabolism, development, behavior, and disease resistance of their multicellular hosts. Because the community structure of symbiont bacteria can influence host health, the characterization of amphibian microbiomes is becoming an increasingly important tool for future conservation in the face of global amphibian declines. Eastern hellbenders are good candidates for a microbiome study because they have seen substantial declines in recent decades and learning more about the environmental and physiological drivers of the hellbender microbiome could inform management decisions. Previous studies have explored the cutaneous microbial communities of hellbenders. However, none have compared the microbiomes of various age classes to look for an ontogenetic shift. Additionally, previous studies did not include the comparison of captive hellbenders to those of wild populations. We obtained samples from hellbenders within 5 rivers across the Monongahela National Forest, West Virginia from April to September 2017 and from a captive, juvenile population. Results suggest an ontogenetic shift in cutaneous bacterial community structure could take place as hellbenders age from larvae to adults. There were also differences between captive and wild individuals although studies with greater replication of captive populations would need to be done to further support this. No significant variation among microbiomes was observed between wild sampling locations throughout sampling sites in West Virginia. Additionally, water flow rates and water temperature were found to significantly influence bacterial community divergence