In science, nothing is real until someone has done a study on it. Back in the early days of this project, we knew that Ranavirus was killing tens of thousands of frogs each year in the UK. We thought it was likely that this would have long-term impacts, but no-one had the data to back up the suspicions. One of the first bits of research that we did using the Frog Mortality Dataset was designed to fix this gap.
We used the Frog Mortality Dataset (see the first blog post!) to find a set of frog populations that had shown signs of Ranavirus infection for about a decade. We then found a set of frog populations with no history of disease, where the pond owners had kept records of their frogs for at least a decade. People in the UK love their gardens, and many of them are close to obsession when it comes to their garden wildlife. We found pond owners with tatty notebooks dating back to the 1980s with the dates of first frog spawning each year, number of clutches of frog spawn and plenty more bits and bobs. In the end, this was absolutely critical data for us.
Using a combination of pond owners notes, and the Frog Mortality data, we managed to get the number of frogs at each pond in 2008, and ten years before. This told us that infected frog populations had about 80% fewer frogs in them compared to a decade previously - while the uninfected populations hadn't change size. So, for the first time, we had good evidence that this disease can cause large, long-term population declines. There aren't many diseases with this sort of mortality rate - myxomatosis in rabbits, and ebola in humans are roughly on a par.
The full paper is available here.
We used the Frog Mortality Dataset (see the first blog post!) to find a set of frog populations that had shown signs of Ranavirus infection for about a decade. We then found a set of frog populations with no history of disease, where the pond owners had kept records of their frogs for at least a decade. People in the UK love their gardens, and many of them are close to obsession when it comes to their garden wildlife. We found pond owners with tatty notebooks dating back to the 1980s with the dates of first frog spawning each year, number of clutches of frog spawn and plenty more bits and bobs. In the end, this was absolutely critical data for us.
Using a combination of pond owners notes, and the Frog Mortality data, we managed to get the number of frogs at each pond in 2008, and ten years before. This told us that infected frog populations had about 80% fewer frogs in them compared to a decade previously - while the uninfected populations hadn't change size. So, for the first time, we had good evidence that this disease can cause large, long-term population declines. There aren't many diseases with this sort of mortality rate - myxomatosis in rabbits, and ebola in humans are roughly on a par.
The full paper is available here.