Bullfrogs Do Not Just Spread Deadly Amphibian Fungus, But Also Die From It: Study

A latest finding by researchers at Oregon State University and the University of Pittsburgh states that bullfrogs are not just carriers of the deadly amphibian fungus but are also vulnerable to it.

This two year study published in a professional journal EcoHealth contradicts the previous findings that state bullfrogs are tolerant carrier hosts that just spread the disease.

By proving that bullfrogs are not the sole culprits in spreading the fungus, the researchers have brought in further complications to the question as to why amphibians are declining or facing extinction.

A study done earlier had shown how the African clawed frogs that were used to determine pregnancy in the early 20^th century were carriers of a same virus that infected other species of frogs and salamanders and caused extinction of several amphibian species, reports HNGN.

 According to the researchers, nearly 40 percent of all amphibian species are either facing extinction or are declining at a fast rate. This could be due to several factors such as the fungus, change in climate, destruction of habitat, pollution, invasive species or increased UV-B light exposure.

In this study the researchers raised bullfrogs from eggs in a controlled experiment. They spotted one strain of the pathogen Batrachochytrium dendrobatidis (Bd) or chytrid fungus in the species under experiment. They discovered that the two year old juveniles were more susceptible to the strain.

The Bd fungus grows on the amphibian skin and causes the thickening of the skin by 40 percent and sometimes causes heart attacks just weeks after infection, conservation biologist at San Francisco State University, Vance Vredenburg, who was not involved in this study, was quoted as saying by HNGN.

Though bullfrogs are not good hosts for the fungus, it is still a mystery as to why the fungus has spread so fast, causing high mortality rates.

Andrew Blaustein, a distinguished professor of zoology at OSU and international leader in the study of amphibian declines, said in a press statement "One possibility for the fungal increase is climate change, which can also compromise the immune systems of amphibians. There are a lot of possible ways the fungus can spread. People can even carry it on their shoes."