Snakes worldwide are increasingly facing the specter of extinction, with habitat loss and disease emerging as a serious concern. One of essentially the most serious diseases affecting snakes is ophidiomycosis, commonly referred to as fungal disease of snakes, attributable to the fungus (). Since researchers first identified the disease nearly 20 years ago, it has been present in many species of snakes.
In an effort to higher understand the general health of untamed snakes, researchers within the southeastern United States investigated seven different pathogens in local snake populations. Their goal was to match infection rates across species, locations, and time. The results were published.
“Fungi and parasites (), appear to be the most important infectious agents in free-ranging snakes in the southeastern United States,” said first writer Dr. Corina Meschen (formerly Corina Hazelrig), a researcher on the University of Georgia. “We also show that increased risk of ophidiomycosis was strongly associated with infection in free-ranging indigenous snakes.”
The researchers surveyed a whole lot of untamed snakes.
The study, funded by the Morris Animal Foundation, sampled greater than 500 snakes from two wildlife sanctuaries in South Carolina and Florida, covering 29 species. The researchers also collected additional samples from other regions of the southeastern United States every time possible.
Most of the snakes were captured alive so scientists could skin them and collect blood samples before release. A small variety of snakes that died on roads or within the wild underwent detailed postmortem examinations that included tissue collection.
“For about 10 years, independent snake research has been almost entirely focused. We wanted to look at snake health at a more holistic level and really take a broader view,” said Machin.
Multiple infections are common in wild snakes.
The researchers discovered that lower than 20 percent of the snakes showed no signs of infection.
The most prevalent pathogen was the bacterium, which appeared in 63 percent of the snakes. Another common infection got here from spp., a tick-borne parasite present in 53% of animals.
The scientists also detected antibiotic-resistant spp. Bacteria in 18 percent of snakes. These bacteria could cause upper respiratory disease and have never before been reported in wild snakes within the United States.
Many snakes were carrying multiple pathogen at the identical time. Overall, 44% of snakes had multiple infections. About 29% had two pathogens concurrently, while 11% had three infections and three% had 4 different pathogens.
“When an animal is sick with an infection, its immune system is compromised, increasing the risk of further disease progression from other infectious agents that may have once been subclinical,” Machin explained.
The pygmy rattlesnake is very endangered.
The study also found that some species of snakes are more prone to certain diseases than others.
Pygmy rattlesnakes showed particularly high rates of snake fungal disease. Of the 34 rattlesnakes tested, 12 tested positive, and lots of showed visible signs of the disease. In comparison, only certainly one of 55 eastern ribbon snakes and three of 36 ringed snakes tested positive.
Rattlesnakes were also the species most ceaselessly affected by this, an invasive crustacean parasite commonly referred to as snake lungworm. Fourteen of the 34 rattlesnakes carried the parasite. In several other snake species, Ro infections were much less common or completely absent, including Florida green water snakes.
“We hypothesize that some species with poor general population health, particularly rattlesnakes with historical and current increased risks of human persecution, may be more susceptible to subsequent disease infection,” Meschen said. “Also, increased prevalence of pygmy rattlesnakes was expected, as they primarily feed on lizards and frogs known to transmit the parasite.”
Risk of infection by geography and skin damage
Location also appeared to affect infection patterns. Snakes sampled in Georgia were more more likely to test positive, while infections were found only in Florida snakes.
Skin loss was one other essential factor. More than 30% of snakes with skin lesions tested positive for snake fungus disease, in comparison with only 2% of snakes without lesions.
Disease risks and safety concerns
The researchers noted several limitations within the study. Sampling took place in just a small variety of counties, meaning the outcomes may reflect local environmental conditions slightly than the complete southeastern United States.
The team also explained that detecting live snakes will be difficult because testing relies on gut samples. Because snakes often go without food for long periods of time, usable specimens aren’t at all times available. As a result, true infection rates could also be higher than reported.
Nevertheless, the researchers say the findings could play a very important role in wildlife conservation and invasive species management. Burmese pythons and brown anoles, each invasive species within the United States, are known carriers.
“Our data provide important information on which pathogens native snakes may harbor but also which are potentially immature. This may inform measures that are needed to prevent the spread of pathogens from captive snakes,” Machin concluded. “When moving wildlife, it’s important to consider what pathogens may be transported with them — and the potential downstream effects.”