Over the past decade, biologists in the United States have been tracking the rise of a deadly disease affecting snakes. Exactly where it came from, how it spreads and what it means for infected snake populations are all still rather mysterious. Now, a new report has revealed the disease is popping up in far more places – and in more snake species – than we thought. Snake Fungal Disease (SFD) is a skin condition that first caught scientists' attention back in 2006, when it struck a population of timber rattlesnakes in New Hampshire, cutting their numbers dramatically. Two years later, it wreaked similar havoc on rattlers in Illinois. Since then, the number of reports has continued to rise. Just this past year has seen reports coming out of Virginia, Louisiana and Ontario – the first reported case outside the United States. The new report, put together by scientists from the US Geological Survey and colleagues, delivers the hard numbers: SFD has now been reported from at least 20 different states (plus Ontario), and it's affected more than 30 different snake species, from rattlers to rat snakes.
The disease has been on scientists' radar for only a short time, so they're still working on understanding it, but last year, the culprit was finally identified: a fungus named Ophidiomyces ophiodiicola. The disease causes blisters, ulcers, scabs and various other skin conditions in infected snakes. Most of the time, the effects seem to be fairly mild, but in some cases – for reasons that aren't fully understood – it can be extremely dangerous.
The New Hampshire outbreak detected in 2006 caused a 50% decline in the already-small population of local timber rattlesnakes. In Illinois, the fungus struck an endangered population of massasaugas (pygmy rattlers). A more recent case caused a decline of almost 20% in a community of Lake Erie watersnakes, a species that was only recently removed from the Threatened Species List.
"Some snake populations in the eastern and Midwestern US could eventually face extinction as a result of SFD," says Jeff Lorch, lead author of the new study. "[W]e still need to determine why these mild infections are becoming more severe and fatal in certain areas.
Source: Earth Touch News, December 5, 2016
http://www.earthtouchnews.com/discoveries/discoveries/mysterious-snake-…
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