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The fungal pathogen Batrachochytrium dendrobatidis ( Bd ) is implicated in global mass die-offs and declines in amphibians. In Mesoamerica, the Bd epidemic wave hypothesis is supported by detection of Bd in historic museum specimens collected over the last century, yet the timing and impact of the early stages of the wave remain poorly understood. Chiropterotriton magnipes , the only obligate troglodytic Neotropical salamander, was abundant in its small range in the decade following its description in 1965, but subsequently disappeared from known localities and was not seen for 34 years. Its decline is roughly coincident with that of other populations of Neotropical salamanders associated with the invasion and spread of Bd . To determine the presence and infection intensity of Bd on C. magnipes and sympatric amphibian species (which are also Bd hosts), we used a noninvasive sampling technique and qPCR assay to detect Bd on museum specimens of C. magnipes collected from 1952 to 2012, and from extant populations of C. magnipes and sympatric species of amphibians. We also tested for the presence of the recently discovered Batrachochytrium salamandivorans ( Bsal ), another fungal chytridiomycete pathogen of salamanders, using a similar technique specific for Bsal . We did not detect Bd in populations of C. magnipes before 1969, while Bd was detected at low to moderate prevalence just prior to and during declines. This pattern is consistent with Bd -caused epizootics followed by host declines and extirpations described in other hosts. We did not detect Bsal in any extant population of C. magnipes . We obtained one of the earliest positive records of the fungus to date in Latin America, providing additional historical evidence consistent with the Bd epidemic wave hypothesis. Genotyping results show that at least one population is currently infected with the Global Panzootic Lineage of Bd , but our genotyping of the historical positive samples was unsuccessful. The lack of large samples from some years and the difficulty in genotyping historical Bd samples illustrate some of the difficulties inherent in assigning causality to historical amphibian declines. These data also provide an important historical baseline for actions to preserve the few known remaining populations of C. magnipes .
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Implementation of a Citizen Science Program to Assess Chytridiomycosis (Batrachochytrium dendrobatidis) Prevalence in Amphibians across Oklahoma, USA
Global amphibian populations are declining rapidly, due largely to infectious diseases such as chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). The Herpetology Department at the Sam Noble Museum has screened for Bd prevalence among amphibian communities across Oklahoma for over five years, providing ongoing data about the disease’s prevalence and distribution. Recently, the museum partnered with other Oklahomans through a citizen science project allowing participants to sample their local amphibian communities for Bd. Our project targeted K–12 students in Oklahoma to promote curiosity in science and to foster an interest in pursuing career paths in science, technology, engineering, and mathematics (STEM). The multi-year baseline citizen science dataset we obtained shows a lower Bd prevalence compared to samples collected from trained researchers. In this study, we juxtapose the two datasets and make observations on the feasibility of the citizen science program. Results from the program suggest that kit return rates were average for a project of this scale, and many participants could correctly identify amphibian species. Our findings indicate that the citizen science initiative is successful in increasing statewide amphibian disease sampling range and heightening the public’s awareness of this global amphibian epidemic.
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- Award ID(s):
- 1657648
- PAR ID:
- 10470898
- Publisher / Repository:
- Oklahoma State University Library
- Date Published:
- Journal Name:
- Proceedings of the Oklahoma Academy of Science
- Volume:
- 102
- ISSN:
- 0078-4303
- Page Range / eLocation ID:
- 1–18
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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