A rare fungal infection is providing an additional threat to endangered rattlesnakes. A small number of eastern Massasauga rattlesnakes that are in decline due to loss of habitat and environmental issues in Southern Illinois, America.
But Matthew Allender, a visiting instructor in comparative biosciences at the University of Illinois, has discovered the protected creatures are being killed by the rare Chrysosporium fungus.
The snakes that are protected by the Endangered Species Act can be found during spring in the shallow wetlands of Southern Illinois, America, and later move to the drier uplands. The fungus often attacks certain pet species, but it seldom affects wild animals, says Mr Allender, who is also a wildlife vet.
"Chrysosporium causes disease in bearded dragons and in other snakes and it's a bad bug. We see it in captive animals worldwide, but we don't typically find it in free-ranging animals."
Established studies on the eastern massasauga rattlesnake (Sistrurus catenatus catenatus) never picked up the fungal infection as a problem.
But in 2008 and 2010, four rattlesnakes were discovered in a park in Southern Illinois with ugly head wounds and died weeks later. Post-mortem tests showed they had succumbed to deadly Chrysosporium, which can also infect humans that have weak immune systems.
Biologists in northeast USA have reported over the last five years that timber rattlesnakes have suffered Chrysosporium attacks in the states of Massachusetts and New Hampshire.
Other species in the wild, such as frogs and bats (white-nose syndrome) that have been attacked by other serious fungal infections have suffered extensive fatalities that have threatened their populations, says Matthew Allender. It is not known how the rattlesnakes were infected by the fungus and no treatment is currently available.
Mr Allender views the threat to the eastern massasauga rattlesnake as a warning sign that requires more investigation. If it escalates, it could also further affect humans and other animals, he warns.
To see the study, Chrysosporium sp. Infection in Eastern Massasauga Rattlesnakes, visit the Centers for Disease Control and Prevention (CDC).