Abstract
Emerging pathogenic fungi have become a topic of conservation concern due to declines observed in several host taxa. One emerging fungal pathogen, Ophidiomyces ophidiicola, is well documented as the causative agent of ophidiomycosis, otherwise known as snake fungal disease (SFD). O. ophidiicola has been found to cause disease in a variety of snake species across the United States, including the eastern massasauga (Sistrurus catenatus), a federally threatened rattlesnake species. Most work to date has involved detecting O. ophidiicola for diagnosis of infection through direct sampling of snakes, and attempts to detect O. ophidiicola in the abiotic environment to better understand its distribution, seasonality, and habitat associations are lacking. We collected topsoil and groundwater samples from four macrohabitat types across multiple seasons in northern Michigan at a site where Ophidiomyces infection has been confirmed in eastern massasauga. Using a quantitative PCR (qPCR) assay developed for O. ophidiicola, we detected Ophidiomyces DNA in topsoil but observed minimal to no detection in groundwater samples. Detection frequency did not differ between habitats, but samples grouped seasonally showed higher detection during midsummer. We found no relationships of detection with hypothesized environmental correlates such as soil pH, temperature, or moisture content. Furthermore, the distribution of Ophidiomyces positive samples across the site was not linked to estimated space use of massasaugas. Our data suggests that season has some effect on the presence of Ophidiomyces. Differences in presence between habitats may exist but are likely more dependent on the time of sampling and currently uninvestigated soil or biotic parameters. These findings build on our understanding of Ophidiomyces ecology and epidemiology to help inform where and when snakes may be exposed to the fungus in the environment.
| Original language | English |
|---|---|
| Article number | e0310954 |
| Journal | PLoS ONE |
| Volume | 19 |
| Issue number | 10 |
| DOIs | |
| State | Published - Oct 2024 |
Funding
Evin Carter (EC) submitted grant. Grant was awarded and received by Mark Jordan (MAJ) and Purdue University Fort Wayne. Funded by the Michigan Department of Military and Veterans Affairs. https://www.michigan.gov/dmva The funders played no part in the study design or manuscript preparation. The national guard facility (Camp Grayling) is listed un the NG facilities in the \"Our Agencies section\" and its environmental office staff assisted navigation and dealings with national guard personnel but did not have direct role in data collection. We would like to extend our sincerest thank you to all that played a role in this research. Matthew Kleitch, Carla Lange, Darcia Little, and Cullen Haesler with the environmental office at Camp Grayling were all pivotal in our ability to conduct field work. Their collaboration was greatly appreciated. Additionally, we want to thank Dr. Matthew Allender and his lab for providing plasmids for use during quantitative PCR and MCLAB for sanger sequencing of our PCR products. Furthermore, we thank Jessica Hinson, Emma Browning, and Cody Ewers for assisting with massasauga radio-tracking. Dr. Phil Robinson for implanting radio-transmitters and to the veterinary staff at the Grayling Hospital for Animals for allowing us to use their facilities.