Wildfires disturb the natural skin microbiota of terrestrial salamanders

Host-associated microbiomes contribute to the health of multicellular organisms and have been found to influence immunity, metabolism, and energy uptake. Environmental change can disturb natural associations between wildlife and microbial symbionts, in many cases to the detriment of host health. The response of microbial communities to environmental change may differ depending on the life stage and natural history of the organismal host. We used a North American salamander system to assess how the skin microbiota of amphibians responds to wildfires. In northern Californian redwood/oak forests, we assessed how recent wildfires affected the skin microbiotas of Taricha sp., Batrachoseps attenuatus, and Ensatina eschscholtzii. We found species-specific responses to wildfire disturbance on the alpha diversity of the skin microbiota of terrestrial salamanders, although burning in general altered the composition of the skin microbiotas. We also noted changes in the relative abundance of abundant bacteria found on the skin of terrestrial salamanders. Our study documents the skin microbiota response to an increasing disturbance in western North American ecosystems. In addition, our results highlight the need to consider the effects of increased wildfire regimes/intensities on wildlife-associated microbiotas and animal health.