Graduation Date
Fall 2023
Document Type
Thesis
Program
Master of Science degree with a major in Biology
Committee Chair Name
Karen Kiemnec-Tyburczy
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
John Reiss
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Sharyn Marks
Third Committee Member Affiliation
HSU Faculty or Staff
Fourth Committee Member Name
Adam Cummings
Fourth Committee Member Affiliation
Community Member or Outside Professional
Keywords
Northern California, Ranavirus, Bsal, Bd, Chytrid, Rhyacotriton variegatus, Pathogen, Batrachochytrium, Viral load, Prevalence
Subject Categories
Biology
Abstract
Amphibian population declines around the world have been attributed in part to the emergence of deadly pathogens. However, the severity of the effects of pathogens on amphibian communities can vary by species and location. This study focuses on assessing the prevalence of Batrachochytrium dendrobatidis (Bd), Batrachochytrium salamandrivorans (Bsal), and ranaviruses in populations of southern torrent salamanders (Rhyacotriton variegatus). I also tested for association between environmental factors and the prevalence and viral load of the three pathogens in Northern California. A total of 309 skin swab samples were collected from salamanders in nine sites in Del Norte and Humboldt Counties. A quantitative PCR diagnostic assay was used to detect the presence of pathogen DNA in each sample. Approximately 16% of all R. variegatus swab samples contained ranavirus DNA, but neither Bd nor Bsal were detected. Ranavirus prevalence varied widely across sites (from 0-40%). The water temperature of the salamander’s microhabitat significantly influenced an individual’s ranavirus load. Additionally, ranavirus prevalence was significantly different across seasons. Ranavirus prevalence was highest in the winter, but viral load was highest in the spring. This study provides the first evidence of ranavirus presence in R. variegatus.
Citation Style
JWM
Recommended Citation
Sandoval, Marilyn Violeta, "Prevalence of Batrachochytrium and Ranavirus in southern torrent salamanders (Rhyacotriton variegatus) in Northern California" (2023). Cal Poly Humboldt theses and projects. 705.
https://digitalcommons.humboldt.edu/etd/705