Revisiting the enigmatic: emergence of Bd coincide with amphibian decline in Los Andes of Ecuador

 

Authors
Manzano Pasquel, Andrea Lisethe
Format
Article
Status
publishedVersion
Description

The enigmatic disappearances of members from the genera Atelopus,Gastrotheca,and Telmatobius in Los Andes of Ecuador has puzzled scientist for decades. Among the suspected culprits is the amphibian chytrid, Batrachochytrium dendrobatidis (Bd). Notorious for its involvement in amphibian decline elsewhere in the neotropics, to date, no evidence has linked Bd to the population crashes of the late 80?s and early 90?s occurring in the region. However,few studies have examined the historical records for the presence of Bd on critically endangered and extinct species last seen during the enigmatic declines. In this report,a survey was conducted on 1109 archived specimens of 29 species from the genera Atelopus,Gastrotheca and Telmatobius collected throughout Los Andes of Ecuador from 1950 to 2010, for the presence of Bd on specimens collected before, during and after the major decline events. We also sample 257 field caught amphibians of 10 species of the genera Atelopus, Gastrotheca and Pristimantis to assess the current dynamics of the pathogen among surviving populations. Using a non-??invasive PCR sampling technique in both our historical and field surveys, the overall prevalence rate of Bd in archived amphibians was 30.72% (338/1100), and 8.56% (22/257)in contemporary populations. These data document the emergence of Bd in Ecuador in the mid 1970?s and highlight a significant increase in Bd prevalence and infection intensity during the late 80?s and early 90?s. Our data support the notion that Bd epizootics were a primary driver in the extirpation and extinction of at least 80% of the Andean frogs, and coincide with the population crashes of the late 80?s and early 90?s. However, our contemporary field survey found Bd prevalence and infection intensity to be low, suggesting remaining populations and species may be less susceptible to the effects of Bd. Further research is needed to understanding the current threat Bd poses on Ecuador?s amphibians, and whether disease fade-??out, host immunity or host biology may explain the current dynamics of Bd in the Ecuadorian Andes.

Publication Year
2014
Language
eng
Topic
ECOLOG?A
CONSERVACI?N DE ANFIBIOS
ENFERMEDADES INFECCIOSAS
ANDES DE ECUADOR
Repository
Repositorio SENESCYT
Get full text
http://repositorio.educacionsuperior.gob.ec//handle/28000/1504
Rights
openAccess
License
restrictedAccess