Dóra Holly

1 Introduction Chytridiomycosis is an infectious disease of amphibians that is caused by the chytrid fungi Batrachochytrium dendrobatidis (Bd) (Longcore et al. 1999) and Batrachochytrium salamandrivorans (Martel et al. 2013) that has resulted in the extinction of at least 70 species and contributed to severe population declines in hundreds of amphibian species in the last few decades (Skerratt et al. 2007; Lips 2016; O'Hanlon et al. 2018; Scheele et al. 2019).

Statistical analyses We analysed data on the two species separately. We calculated the prevalence data with 95% confidence intervals using QPWeb ver. 1.0.15 (Reiczigel et al. 2019) (Supporting information). For all other analyses, we used the R computing environment, ver. 4.0.4 (www.r-project.org). Before thermal treatment, Bd prevalence was low in both species, so we did not perform statistical analyses on pre-treatment Bd prevalence and infection intensity.