Prevalence and geographic patterns of Batrachochytrium dendrobatidis in Texas
Villamizar Gomez, Andrea
Over the past 50 years, amphibian populations have undergone dramatic declines worldwide. Several hypotheses have been proposed to explain the causes for the decline of these populations. Contributing factors include habitat loss, shifts in temperature and rainfall patterns, changes in UV-B, and contamination through anthropogenic activities, and Emergent Infectious Diseases. Batrachochytrium dendrobatidis (Bd) is the pathogen that causes chytridiomycosis, an emerging infectious pathogen, known to be causing declines of amphibians across the globe and threatening overall ecosystem health. While chytridiomycosis in North American amphibians has attracted interest from researchers, the prevalence of this pathogen in Texas remains largely unexplored. To address this deficit, I collected samples during one year from five Wildlife Management Areas across a gradient precipitation. These results suggest that community composition, and differences in environmental conditions affect the prevalence of Bd in an area, suggesting that areas with higher species richness and higher annual precipitation have increased pathogen prevalence. Then, to understand Bd prevalence in time and its historic distribution in Texas, I examined the temporal range of the pathogen’s prevalence, using museum collection specimens dating from 1930 up to 2010. The earliest detection of Bd in Texas was confirmed to be in 1936, suggesting that this pathogen is enzootic to the region. We also determined two pathogen hotspot areas in Central and East Texas. With this study, we provide an updated assessment of the prevalence of the historic and current distribution of Bd among species as well as across the landscape of Texas. It may also reveal species that are not susceptible to the pathogen where their presence can help mitigate the spread of this disease and could aid in the conservation efforts for endangered species
Batrachochytrium dendrobatidis, Chytridiomycosis, Texas, qPCR
Villamizar Gomez, A. (2019). <i>Prevalence and geographic patterns of Batrachochytrium dendrobatidis in Texas</i> (Unpublished dissertation). Texas State University, San Marcos, Texas.