Projects
Sierra Nevada Retrospective Analysis
Recommended Citation:
Butler H. 2017 "Sierra Nevada Retrospective Analysis" AmphibiaWeb: Amphibian Disease Portal.
Data Last Modified: Mon Jan 04 2021
Project Description
Abstract excerpt: In the Sierra Nevada mountains of California, USA, conspecific populations of frogs currently exhibit dramatically different host/ Bd-pathogen dynamics. To provide a temporal context by which present day dynamics may be better understood, we use a Bd qPCR assay to test 1165 amphibian specimens collected between 1900 and 2005. Our historical analyses reveal a pattern of pathogen invasion and eventual spread across the Sierra Nevada over the last century. Although we found a small number of Bd-infections prior to 1970, these showed no sign of spread or increase in infection prevalence over multiple decades. After the late 1970s, when mass die offs were first noted, our data show Bd as much more prevalent and more spatially spread out, suggesting epizootic spread. However, across the ~400km2 area, we found no evidence of a wave-like pattern, but instead discovered multiple, nearly-simultaneous invasions within regions. We found that Bd invaded and spread in the central Sierra Nevada (Yosemite National Park area) about four decades before it invaded and spread in the southern Sierra Nevada (Sequoia and Kings Canyon National Parks area), and suggest that the temporal pattern of pathogen invasion may help explain divergent contemporary host pathogen dynamics. These data were part of Sam McNally's master thesis.
Information
Project PI: Vance Vredenburg
Project Contact: Helen Butler
Dataset DOI: https://n2t.net/ark:/21547/Ars2
Publication DOI: https://doi.org/10.1371/journal.pone.0219981
Project Data - Public
Events: 509 || Samples Collected: 1197
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