Presence of Batrachochytrium dendrobatidis in feral populations of Xenopus laevis in Chile

Abstract

Batrachochytrium dendrobatidis (Bd) is a causal agent of disease and population decline of amphibian populations, and the extinction of several anuran species worldwide. Diverse hypotheses have been provided for the emergence of this fungus in different continents, ranging from global climate change to the vectoring of Bd via the international trade in amphibian species. In order to address these hypotheses, it is important to assess the current distribution of Bd in the context of introduced nonnative amphibian species. We sampled several populations of the African clawed frog Xenopus laevis across its distribution in Chile in order to detect the presence of B. dendrobatidis and evaluate the role of this frog as a potential vector. In three of ten sites sampled, individuals harbored B. dendrobatidis infection, with an overall prevalence of infection across the studied populations of 24% (14 positive out of 58 analyzed specimens). The rapid spread exhibited by this frog within Chile suggests that transpecific transmission of the pathogen is possible, perhaps jeopardizing native species. This finding indicates the urgent need to establish long-term monitoring population programs in order to allow early detection disease-driven changes in the sizes of native populations, allowing the prompt application of conservation practices.This research was conducted under permit of the Servicio Agrı´cola y Ganadero (SAG) and Corporacio´n Nacional Forestal (CONAF) from Chile and supported by the Fundacio´n BBVA (PI: J.B.) and the Natural Environmental Research Council, NERC, UK (PI: M.F.)

The Population Decline and Extinction of Darwin’s Frogs

“…Xenopus laevis has been associated with the emergence and global spread of the amphibian disease chytridiomycosis, caused by Batrachochytrium dendrobatidis ( Bd ) [59], [60]. Recently, Bd has been identified in wild populations of X. laevis in Chile [61] and chytridiomycosis has been reported as a cause of mortality of R. darwinii in captivity [36], [43]. The impacts of Bd on sympatric wild amphibians, including Darwin’s frogs, in Chile have not been investigated.…”

Potential distribution of Batrachochytrium dendrobatidis in Argentina: implications in amphibian conservation

“…Ron (2005) described specific regions in South America such as the Brazilian Atlantic forest, the temperate forest in Chile and western Argentina (south to 308 S), northeastern Argentina, Uruguay and Paraguay. Later findings of the fungus in native and exotic species of nine countries in and around these regions support the hypothesis (i.e., Ron & Merino, 2000;Mazzoni et al, 2003;Seimon et al, 2005;Barrionuevo & Mangione, 2006;Carnaval et al, 2006;Fox et al, 2006;Barrionuevo et al, 2008;Ruiz & Rueda-Almonacid, 2008;Arellano et al, 2009;Borteiro et al, 2009;Ghirardi et al, 2009;Solis et al, 2009). In Argentina, the earliest evidence of this fungus dates from 2002 (Herrera et al, 2005), and since then new reports have expanded the extent of B.d.…”

Introducción intencional de fauna exótica y futuros invasores: ¿Seguimos tropezando con la misma piedra una y otra vez?

“…De las 17 especies animales vertebrados cuyo manejo ha sido considerado prioritario, gran parte de ellas fueron introducidas con fines domésticos (e.g., Sus scrofa Linnaeus, 1758; Cervus elaphus) o comerciales (e.g., N. vison). Otro caso que preocupa, es X. laevis, dado que se encuentra naturalizada y en expansión de su rango secundario en Chile (Lobos y Jaksic 2005), además ha sido identificada como vector de Ranavirus (Robert et al 2007) y hongo quítrido, Batrachochytrium dendrobatidis (Longcore, Pessier et DK Nichols) (Solís et al 2010). Además se detectó que tres de los géneros que han sido introducidos entre el 2009-2015 a la fecha de introducción ya presentaban poblaciones natu-ralizadas (Nasua spp., Oryctolagus spp., y Sus spp.)…”