By Phil Jervis
As part of my MRes Tropical Forest Ecology course I was required to undertake a research project involving an extended fieldwork component. After getting in touch with Prof. Mat Fisher and Dr. Andres Merino-Viteri from Pontificia Universidad Católica del Ecuador (PUCE) in Quito, I set about designing a project which would investigate which biotic and abiotic variables influence the presence of Bd across Ecuador.
Ecuador is one of the most biodiverse countries on the planet and has an incredible total of 587 species of amphibian, with more being added to this total each year. My sampling sites were spread across a large altitudinal range to cover diverse habitats from lowland tropical forests in the Amazon basin to cold, high altitude Andean paramo. Despite this diversity of species and habitats, there are many threatened species which have experienced heavy declines due to habitat loss and chytridiomycosis. Of particular interest to me were the endangered montane amphibians, such as Atelopus palmatus (IUCN classified as data deficient, but known from a single remaining site) and Hyloscirtus lindae (IUCN classified as Vulnerable), many of which suffered enigmatic declines which were attributed to chytridiomycosis.
With the help of Pol Pintanel, Pauli Romero, Freddy Almeida, Ricardo Elbay and Stephen Hopkins from PUCE, we sampled across 17 sites in Ecuador over a period of two months in the spring of 2017. Each amphibian was captured by hand or net, swabbed with a sterile cotton swab and returned unharmed to where they had been found. We managed to sample over 300 individuals across 40 species, including representative from all three orders of amphibians (frogs, salamanders and caecilians).
Available Bd infection data for the sites and species involved in the study was limited and our survey showed that Bd is widely distributed throughout the country, not confined to the high altitude Andean cloud forest and paramo where many of the widely publicised declines of montane amphibians, such as Atelopus sp., occured. Through examining the fungal and bacterial diversity of the environmental samples and skin swabs we are hoping to observe differences in the community of micro-organisms which may explain the heterogeneity of Bd prevalence and susceptibility between animals with different life strategies and habitat preferences.
This fieldwork was made possible by the vast expertise and knowledge provided by Dr. Andres Merino-Viteri and Dr. Santiago Ron, and their respective teams in the Herpetology Department at PUCE. I hope to return to Ecuador later this year to continue this project and work specifically with Atelopus populations to investigate how Bd susceptible species are able to persist in heavily restricted relic populations. To read more about the herpetological work carried out at PUCE, you can visit the website of Dr. Santiago Ron here. I would also like to thank the Leverhulme Trust for funding the laboratory costs of my analysis.