Rare fungus kills endangered rattlesnakes in southern Illinois

Feb 21, 2012
The eastern massasauga rattlesnake normally spends spring in shallow wetlands and summer in drier upland areas. Credit: Matthew Allender

A small population of rattlesnakes that already is in decline in southern Illinois faces a new and unexpected threat in the form of a fungus rarely seen in the wild, researchers report. The finding matches reports of rattlesnake deaths in the northeast United States.

The eastern massasauga rattlesnake (Sistrurus catenatus catenatus), a candidate for protection under the , suffers from and wherever it is found, said University of Illinois comparative biosciences visiting instructor and wildlife veterinarian Matthew Allender, who led the health investigation. Long-term population studies of the snake – in Illinois and elsewhere – had never turned up evidence of debilitating fungal infections. But in 2008, biologists studying the snake reported to Allender that they had found three sick snakes in a park in southern Illinois, all with disfiguring lesions on their heads. The snakes died within three weeks of their discovery. A fourth snake with a similar syndrome was discovered in the same park in the spring of 2010.

Allender conducted necropsies on the snakes and identified the pathogen that had killed them: Chrysosporium, a that plagues portions of the pet reptile industry but is not normally seen in the wild, he said.

"Chrysosporium causes disease in bearded dragons and in other snakes and it's a bad bug," Allender said. "We see it in captive animals worldwide, but we don't typically find it in free-ranging animals."

Chrysosporium also is emerging as a dangerous infection in humans with weakened immune systems, he said.

Shortly after he first presented his findings at a meeting of the Fish and Wildlife Service, Allender heard from other biologists about similar infections in snakes in the northeast United States.

"They seem to be having a similar problem in timber rattlesnakes in New Hampshire and Massachusetts," Allender said. Although biologists have sporadically identified Chrysosporium in those snakes, the symptoms they report – facial swelling and ulcers and malformations of the jaw – are the same, he said. These infections also occurred only within the last five years.

"Fungal pathogens have been increasingly associated with free-ranging epidemics in wildlife, including the well-known effects of Batrachochytrium dendrobatidis on frog populations globally and white-nosed syndrome in bats," Allender wrote in a December 2011 report in Emerging Infectious Diseases. "Both of these diseases cause widespread and ongoing deaths in these populations that seriously threaten biodiversity across the United States."

Allender sees this new occurrence of a fungal infection in endangered as a "yellow flag" that warrants more study.

"Wildlife diseases and human health are not that different," he said. "And often wildlife are our window into a weakened environment that leads to disease in both people and animals."

Explore further: Salmon forced to 'sprint' less likely to survive migration

More information: wwwnc.cdc.gov/eid/article/17/1… /11-0240_article.htm

add to favorites email to friend print save as pdf

Related Stories

US bans import of Burmese pythons

Jan 17, 2012

The United States announced Tuesday it is banning the import of Burmese pythons and three other species of giant constrictor snakes due to the danger they pose to local wildlife.

Squirrels use snake scent

Dec 19, 2007

California ground squirrels and rock squirrels chew up rattlesnake skin and smear it on their fur to mask their scent from predators, according to a new study by researchers at UC Davis.

Snake venoms share similar ingredients

Dec 20, 2007

Venoms from different snake families may have many deadly ingredients in common, more than was previously thought. A study published in the online open access journal BMC Molecular Biology has unexpectedly discovered three- ...

Battle over a garter snake in Wisconsin

Jul 29, 2006

Wisconsin lawmakers are threatening to remove a snake's protected status unless the state Department of Natural Resources eases regulations on developers.

Recommended for you

Genetically tracking farmed fish escaping into the wild

Aug 20, 2014

European sea product consumption is on the rise. With overfishing being a threat to the natural balance of the ocean, the alternative is to turn to aquaculture, the industrial production of fish and seafood. ...

France fights back Asian hornet invader

Aug 20, 2014

They slipped into southwest France 10 years ago in a pottery shipment from China and have since invaded more than half the country, which is fighting back with drones, poisoned rods and even chickens.

Tide turns for shark fin in China

Aug 20, 2014

A sprawling market floor in Guangzhou was once a prime location for shark fin, one of China's most expensive delicacies. But now it lies deserted, thanks to a ban from official banquet tables and a celebrity-driven ...

Manatees could lose their endangered species status

Aug 19, 2014

About 2,500 manatees have perished in Florida over the last four years, heightening tension between conservationists and property owners as federal officials prepare to decide whether to down-list the creature to threatened ...

User comments : 0