The disease chytridiomycosis has driven dramatic amphibian declines worldwide. In eastern Australia, disease-associated amphibian declines commenced around 1980. Nearly 50 years on, declines continue, with some species showing slow, elevation-restricted losses while others have stabilised and some are recovering. In this PhD exit seminar, I will first present a text analysis mapping 50 years of amphibian-decline research, revealing trends and blind spots in the global research. Second, I will present the results of field-based empirical research assessing the ongoing effects of chytridiomycosis on two frog species across south-eastern Australia. I document a pattern of ongoing declines in high elevation populations of Bibron’s toadlet (Pseudophryne bibronii)/ Dendy’s toadlet (Pseudophryne dendyi), and the recovery of the whistling tree frog (Litoria verreauxii). Additionally, I assess the ability for citizen-science data to track population change. My thesis reveals contrasting long term responses to chytridiomycosis, highlighting the importance of species-level information.

About the Speaker

Jordann Crawford-Ash is a final-stage PhD candidate at ANU’s Fenner School of Environment & Society. Jordann has long been passionate about frog conservation, completing her Honours at UNSW on chytrid fungus dynamics in Sydney’s frog species, and working with the Australian Museum herpetology team on many conservation projects, including the citizen-science app, FrogID, where she identified frog calls across Australia. Her research focuses on the ecological mechanisms that may allow frogs to persist with the now-endemic chytrid fungus (Bd).