Emerging Infectious Pathogens (Bd and Bsal) and San Francisco’s Urban Amphibian Communities
By: Andrés Patino, Allen Ramsey, Debbie Liao, Franchesca Terrado, Lilia Phan, Samson Hman, Surminder Sahota
Department: Biology
Faculty Advisors: Dr. Vance Vredenburg, Dr. Andy Zink, Dr. Gretchen LeBuhn
I’m investigating how chytridiomycosis, a lethal amphibian disease caused by the fungal pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal), is affecting the amphibian populations in habitats within the city of San Francisco. Bd and Bsal are responsible for significant amphibian population declines around the world (Wake and Vredenburg 2008). Over 1000 amphibian species have been infected (there are currently 8,592 species globally; AmphibiaWeb 2023), and population declines have occurred in over 500 species (Vredenburg et al. 2010), with approximately 90 species believed to have been driven to extinction due to Bd epizootics (Scheele et al. 2019). My research will include a disease survey of the amphibian communities found in over 25 parks throughout San Francisco. The disease data (Bd) from amphibian populations will consist of non-intrusive skin swab samples that are tested for pathogen presence using a qPCR assay specific to the pathogens of interest. My research will build upon prior knowledge from a previous master’s student (Jonathan Young) who completed his degree at SFSU in 2015 (Vredenburg Lab). My project will expand the spatial & temporal view of disease dynamics in urban influenced natural habitats. The goal of my project is to identify any potential associations for changes in positive vs negative Bd results seen today (2023). My research is looking at how factors associated with host community composition and the environment impact disease dynamics. My research will help monitor disease (Bd) and begin to analyze how it influences population fluctuations/ declines in an urban environment to better inform current management practices by the city’s agencies.