Researchers have found that human activities are causing the spread of a virus that is deadly to frogs and other amphibians. The virus is spreading quickly in areas with more human traffic, especially wealthy neighborhoods. The findings are in a paper that was just published in the journal Proceedings of the Royal Society B: Biological Sciences.
Ranaviruses are large viruses that infect amphibians, reptiles, and even some types of fish. The viruses cause severe infections that are usually fatal to the diseased animal. Amphibians are already in decline due to climate change, fungal infections, and pollution. The outbreak of pathogens, including ranaviruses, can further devastate local amphibian populations.
A team of scientists utilized data from a citizen science project called the Frog Mortality Project. United Kingdom residents reported any dead, dying, or diseased frogs they found in their area. The researchers combined this information with their own datasets to form spatio-temporal models. The models could be used to analyze and track the spread of ranaviruses.
The team found that ranavirus outbreaks were becoming more common over time. They also discovered that ranaviruses had been introduced to the United Kingdom from other countries, including the United States. The viruses spread much faster in urban areas and other locations with high amounts of human activity. The team also observed another trend—ranaviruses were spreading rapidly in wealthier neighborhoods. Scientists believe this is at least partially due to residents purchasing and releasing animals into garden ponds. Transporting animals from one water source to another is especially risky since it only takes one infected frog to kill all of the amphibians in a pond.
The team’s findings emphasize the value of citizen science projects for collecting large quantities of data. The research team found that human activity was a major contributor to the spread of deadly ranaviruses. The study’s authors recommend that homeowners research reputable animal sellers and avoid moving animals between ponds.
Stephen J. Price et al. Reconstructing the emergence of a lethal infectious disease of wildlife supports a key role for spread through translocations by humans. Proceedings of the Royal Society B: Biological Sciences (2016).