Biologists trying to combat fungal disease being found in Blanding’s turtles; DuPage testing to be done this summer – Chicago Tribune

Biologists have been working for three decades on a recovery project for the endangered Blanding’s turtle throughout the state, including DuPage County, as numbers declined due to an increase in predators and habitat destruction.

Now the species faces a new threat: a fungal disease that eats through the shell creating a Swiss cheese effect.

Recently, three wild Blanding’s turtles in northeastern Illinois tested positive for the fungus. Chicago-area facilities that raise turtle hatchlings before releasing them into the wild also learned that water in 40% of their habitat tubs contained the fungus.

This summer, biologists plan to test for the fungus in the wetlands where the Blanding’s turtles live in DuPage, Lake, Cook, Kane, McHenry, Will, Lee and Ogle counties.

DuPage County is one of the places where the Chicago Zoological Society has been working to save the rare and endangered turtles by breeding them and releasing them into the forest preserve wetlands district.

“When we first learned about the fungus, panic and fear set in,” said Gary Glowacki, manager of conservation ecology with the Lake County Forest Preserve District, where hatchlings are raised.

“Looking at the bigger picture, we’re thinking we’re lucky we caught this early, and that ultimately this will make our recovery program stronger,” said Glowacki.

Since the recovery program started in 1994, nearly 6,000 young Blanding’s turtles have been raised and released into northern Illinois wetlands by biologists.

University of Illinois scientists discovered the fungus – naming it Emydomyces testavorans – after testing turtles with shell disease in zoo collections. They later also confirmed a wild population of endangered western pond turtles in Washington state also had the disease caused by the fungus. The shell disease can lead to infection and premature death.

Though disease-causing agents like fungi and viruses normally appear in the environment, “more fungal diseases have recently been showing up in wildlife,” said Matt Allender, director of the wildlife epidemiology lab at the University of Illinois’ veterinary diagnostic laboratory.

The reasons are unclear, but it could be due to climate change, deteriorating ecosystems, loss of habitat and declining populations.

“A study published 10 years ago found that of all the emerging diseases in plants and animals, 75% were caused by fungus,” Allender said.

In Illinois, a fungus similar to the one found in the turtles is affecting other reptiles, including the state-endangered eastern massasauga rattlesnake. The species has experienced a 90% mortality rate at its last stronghold near Carlyle Lake in southwestern Illinois, Allender said. Many species of snakes in Illinois, including milk snakes in Lake County, have tested positive for the fungus.

White nose syndrome, caused by a fungus, has killed millions of cave-hibernating bats across the eastern United States since the early 2000s. It has also ravaged an Illinois population in LaSalle County, said Brad Semel, an endangered species recovery specialist for the Illinois Department of Natural Resources.

In the case of globally imperiled species like the Blanding’s turtle, diseases can be devastating since the animal’s numbers have already significantly declined, Allender said.

After U of I pathologists found the fungus in the zoo animals, they decided to test the Blanding’s turtles in Illinois even though they weren’t showing any signs of disease. Allender said they caught the fungus early and that gives them hope for preventing an outbreak.

“All stakeholders are on the same page. We’re working to save the turtles, ”he said. His team tests turtles, snakes and other reptiles for signs of disease in a state program called Wellness of Wildlife.

Semel said the Blanding’s recovery program, which he leads, has “literally come to an immediate halt. We have to better understand our actions to see if it could jeopardize these populations, if we are introducing this emerging threat we were not aware of. ”

‘Positive results year after year’

Blanding’s turtles have historically lived across the northern two-thirds of Illinois.

“Conversion of natural lands through urbanization and agriculture has greatly reduced available habitat such that in most cases, remaining Blanding’s turtle populations are small and highly fragmented by roads and development,” Semel said.

The species was listed as endangered by the state in 2009 because it had declined significantly in abundance and distribution and was dependent upon a rare and vulnerable habitat.

“This is a species that needs sedge meadows and high-quality wetlands that were historically present. They need uplands to lay eggs, shallow sedge meadows to forage in summer and deeper water for overwintering, ”Semel said.

Several decades ago, researchers in northern Illinois discovered that when female Blanding’s turtles laid eggs, predators like raccoons, whose numbers are growing in the state, immediately dug them up and ate them.

“There wasn’t any successful reproduction going on,” Semel said. They weren’t finding any young turtles that could, at the age of 10, start reproducing.

The head-start project began in McHenry and DuPage counties. Biologists don wading boots and collect females at egg-laying time, being careful not to harm them. They bring the females to a lab to lay eggs and then return them to the wild. Female Blanding’s turtles take no part in rearing young – they lay the eggs and leave – so taking the eggs doesn’t harm them, Semel said.

Then the biologists raise the hatchlings until the shells are hard enough and the young are big enough to be released into the wild without being preyed upon.

“We’ve been having positive results year after year,” Semel said. “The survivorship is increasing, and turtles hatched in captivity are starting to breed in the wild. We thought if we’re successful, we could start adding to some other populations in Illinois. ”He said.

That’s not going to be happening, at least for now.

Allender said his team has been testing Blanding’s turtles for different diseases for the past six years. In winter, they decided to test samples they had taken from turtles in the wild over the past few years for the newly emerged fungus.

“We didn’t want the Blanding’s turtle to go the way of the western pond turtle,” he said.

The Blanding’s turtle hatchling facilities are now establishing biosecurity protocols such as requiring employees to work with the turtles known to be negative for the fungus before working with those that are positive and to use gloves before handling the turtles.

“The overarching principle of conservation ecology is: Do no harm,” Glowacki said. “It’s a scary thought to think you could be doing more harm than good. We’re at this crossroads. How do we continue to reap the benefits of all of our efforts? It adds a new wrinkle. ”

Karen Terio, chief of the University of Illinois Zoological Pathology Program, said drugs had been identified that could treat the turtles with the fungus.

“But the question is how do you deliver that drug to a turtle? Can we do it as an implant or as a slow-release capsule? ” she said.

Her department is also working on other strategies, including filtration systems that use different wavelengths of light to target the fungus, much like a filter on a fish tank.

The case of the Blanding’s turtle also shows the complexities of helping endangered species recover.

“It’s such a multifaceted approach,” Semel said. “People used to think, we won’t hunt them anymore. That was the most direct approach. Then we realized they needed a place to live. Let’s do habitat management. Then you realize, we have climate change and the timing can be off for some species. For example, Karner blue butterflies are hatching before their food is available.

“Now we’ve added health assessments. “Diseases will be a really critical component in understanding how to recover an endangered species,” he said.

Sheryl DeVore is a freelance reporter.

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