Dr. Brian MIller

MTSU researchers document hellbender’s accelerating decline in Middle Tennessee

(Author’s note: I was aware of the hellbender before interviewing Brian Miller, but did not know the giant salamanders were present on the Highland Rim of Tennessee. Subsequent reading and interviews with other researchers, including Dr. Bill Sutton at Tennessee State University, Nashville, confirm Miller’s statements that hellbenders are vanishing from large portions of Tennessee, and Missouri. The healthy populations in portions of the Great Smoky Mountains and Cherokee National Forest may be an exception to a general trend toward extirpation and, ultimately, extinction).

Brian Miller has been researching hellbenders for decades. He serves on the faculty of Middle Tennessee State University where he teaches in the biology department and mentors younger researchers, many of whom publish their research.

He has even developed a digital “Guide to the Reptiles and Amphibians of Middle Tennessee.” The guide began more than 30 years ago as a dichotomous key for students in his vertebrate zoology class and now includes hundreds of photographs and exceeds 400 pages.

Dr. Miller researches the hellbenders of the Highland Rim, the upland that surrounds Nashville and the Great Basin. Populations of hellbenders in streams of this region are perhaps Tennessee’s most endangered.

QUESTION: I noticed that you specialize in herpetofauna. Most of the research listed on your faculty page is focused on amphibians, but with some papers on snakes. Can you comment about your research?

ANSWER: You are correct that amphibians are my primary research interest, particularly salamanders. However, I also have strong interests in reptiles, and my students and I have conducted research on various species of snakes and turtles.

When did you become interested in hellbenders?

Hellbenders have been of interest to me since I first encountered them while enrolled in a course on herpetology at the University of Missouri in 1977. I was fortunate that the professor of that course, Dean Metter, was involved with research on hellbenders and I began to assist with his research in 1978, in collaboration with Robert Wilkinson at Southwest Missouri State University in Springfield, Missouri.

Chris Petersen was working on his master’s degree with Dr. Wilkinson at that time and he matriculated to the University of Missouri a couple of years later to start on his Ph.D, which was also with hellbenders. Chris and I spent time in the field gathering data for his Ph.D. project until I moved to Washington State to work on my Ph.D.

I was hired into the biology department at Middle Tennessee State University in 1989 and began working with hellbenders in this state in 1990. At that time, I was able to locate populations in several rivers in Middle Tennessee, including a large population in the Collins River. I decided to concentrate my efforts on this population and one in the Buffalo River.

Of note, the population I worked with in the Collins River was dominated by large adults, whereas the population in the Buffalo River consisted of many age classes, including young individuals.

The Collins River situation was like what I was familiar with in Missouri and Arkansas populations. Unfortunately, by the early 2000s the population I was working with in the Collins River was gone; however, populations remain in the Buffalo River. My research with hellbenders during the past decade has been concentrated in streams in the Western Highland Rim.

Do you work with both subspecies, the Ozark, and the Eastern hellbender?

I worked with both subspecies while a student at the University of Missouri when assisting with projects in the Metter lab, but since I moved to Tennessee, I have worked only with Tennessee populations.

What do you perceive as the greatest threats to hellbender populations?

I am not certain why most populations of hellbenders are in decline rangewide, but suspect that habitat alteration, including sedimentation, and disease are involved in many if not all areas where declines are occurring. Lack of recruitment of young is a common theme of populations that decline. 

Bears stand by a roadside guardrail.  Bridget Donaldson, Virginia Transportation Research Council

Safe Passage initiative calls for wildlife and human protections along mountain highways

Jean Loveday is driving her husband, Tom, home from a doctor’s appointment in Johnson City, Tennessee. Their Toyota pickup truck is winding along Interstate 26, not far from the North Carolina state line north of Asheville.

“Human infrastructure is making it increasingly difficult for wildlife to follow their natural patterns of movement across the landscape,” says Hugh Irwin, a landscape conservation planner with The Wilderness Society who raised concerns back in the 1990s about I-40 being a barrier to wildlife movement. “Historically too little thought and planning has gone into wildlife needs, and our current infrastructure fails to provide for wildlife passage.”

Passionate discussions led to action, and soon more than 80 individuals from nearly 20 federal, state, Tribal, and non-governmental organizations were collaborating to make this section of roadway more permeable for wildlife and safer for people. 

Roadkill’s “Pernicious Twin”

The intersection of roads and wildlife is a safety issue that is not unique to North Carolina and Tennessee. According to the Federal Highway Administration, an estimated two million large mammals are killed on roads in the United States each year, resulting in more than 26,000 human injuries and at least 200 human fatalities.

For years, road ecologists around the world have been working to mitigate highways that were originally designed without consideration for wildlife. Europe, Canada, Mexico, and many U.S. states have already created effective wildlife road crossings. Recent articles and videos featuring large wildlife overpasses in Utah and Texas have been shared widely on social media.

Senior Research Ecologist Marcel Huijser (pronounced ‘Houser’) with the Western Transportation Institute at Montana State University in Bozeman has contributed to road ecology studies for more than two decades. He cites three main reasons why people care about this issue: the desire for wildlife conservation, concern for human safety, and economics. “No matter who you are, where you live, or what you do for a living, you’re going to care about at least one of these,” he says.

On November 26, 2019, The Atlantic ran an auspicious road ecology article by Ben Goldfarb titled “How Roadkill Became an Environmental Disaster.” Focusing on the giant anteaters of Brazil, whose range is — you guessed it — bisected by a huge highway, the epic, riveting story introduces readers to Evelyn the anteater and a cast of road-weary researchers. One particular Goldfarb quote became the motto for researchers assessing wildlife movement and mortality in the Pigeon River Gorge: “Collisions may be road ecology’s most obvious concern, but fragmentation is roadkill’s pernicious twin.”

Conservationists point out the gravity of individual animals being killed on roads. But when they no longer try to cross, it can signal an even more dire situation.

“When wildlife finally stops even trying to cross, the highway has become a barrier,” says Hunter. “The ‘barrier effect’ is not to be confused with the concrete Jersey barriers that prevent many individual crossings. When a whole population stops crossing the road, that means their habitat is now fragmented, preventing the healthy genetic exchange that species need to thrive.”

Ron Sutherland works to restore, reconnect and re-establish wildlife corridors that have been fragmented throughout the eastern United States in his role as chief scientist with Wildlands Network, the organization that kicked off discussions about mitigation to I-40 in 2015. He defines habitat connectivity as the degree to which organisms are able to move freely across the landscape.

“Habitat connectivity can be very high, such as in a remote and intact wilderness,” he says, “or it can be very low, such as in a city park surrounded on all sides by busy highways.”

Sutherland points out that people often get wildlife corridors and wildlife road crossings confused.

“A wildlife corridor is the term we use for a defined movement pathway that, if protected or restored, would provide essential habitat connectivity for one or more species,” he says. “They can be easy to see — such as a vegetated trail alongside a roadway — or nearly invisible and defined only by the movements of the animals.”

A wildlife road crossing, on the other hand, is “a structure that is designed to allow wildlife to safely cross over or under a busy road,” he says. “So, of course it follows that one of the best places to put wildlife road crossings is where you have a wildlife corridor that gets cut off by a highway.”

Read the rest of the story at The Appalachian Voice. 

Ephemeral birds of lasting beauty dependent on Tennessee forest

Think azure. A male cerulean warbler is sky blue. And to see one, you have to climb to the tops of certain Appalachian ridges and look toward the wild blue. To see one is to see a bit of heaven in an eight-gram bird.

East Tennessee’s Royal Blue Unit is not named in honor of the cerulean warbler but it’s appropriate to think so. The land parcel is part of the North Cumberland Wildlife Management Area and is one of the few places — very few places — the sky-blue passerines still nest in North America. It is estimated that 80 percent of the remaining population nests in the Appalachians. 

The cerulean is the fastest declining migratory songbird in North America, said ornithologist David Aborn, an assistant professor of biology, geology and environmental science at UT Chattanooga. The Breeding Bird Survey estimates that cerulean warbler population declined by 70 percent between 1966 and 2008.

“The species is not in danger of imminent extinction, but is rare enough to warrant concern, and its future is not assured,” the U.S. Fish and Wildlife Service reported in 2020.

Currently a management goal of “no net loss” is in place. “Management programs can be instituted at the present time that do not require major changes in land-use practices, but do consider silviculture appropriate to producing habitat for the species,” the report concluded.

The American Bird Conservancy and ProAves Colombia purchased 500 acres of rural land identified as wintering sites for the migratory bird. The Cerulean Warbler Reserve is the first in Latin America set aside for a migrant bird. It’s a start. But the beautiful bird faces many challenges here and abroad. 

Smokies biologist: Bear vs. hog video highlights nature taking its course

The Chattanooga Zoo will soon open an exhibit to hellbenders, such as the one seen here in a tank at the zoo.  Courtesy Chattanooga Zoo

New hellbender exhibit at Chattanooga Zoo will serve as a hub for cooperative research

Thanks to grants from two generous organizations, some oft-elusive hellbenders have a new home at the Chattanooga Zoo. The Hiwassee Education and Research Facility is nearly complete, and it features hellbender exhibits and a classroom. The exhibit includes juvenile hellbenders hatched from eggs collected from the Duck River in central Tennessee in 2015.  

The zoo is also fabricating a stream environment exhibit that will house nine larger sub-adult hellbenders, each about 10 years old and 14.5 inches long. Visitors can observe hellbenders feeding in the completed exhibit, but it will be open only during limited hours. After the project’s completion, the zoo plans to partner with researchers who hope to learn more about hellbenders. 

“The Chattanooga Zoo is thrilled at the introduction of its new Hiwassee Hellbender Research Facility,” zoo officials said in a statement to Hellbender Press. 

“We believe that this new facility will open rare opportunities for guests to be educated on this otherwise elusive native species, and that the project would lead to important strides made in hellbender research. 

“From all of this, our hope is for more conservation efforts made in our local waterways, also known as the eastern hellbender’s home.”