Josh Ennen, MC alumnus, discovers new turtle species

July 20, 2010
Contact: Karen B. Eldridge, Director of Communications

Setting traps and documenting reptile populations in the Great Smoky Mountains back in 2001, Josh Ennen never dreamed he'd one day be credited for discovering a new animal species.

Ennen, then 20 years old and a Maryville College student, was assisting with the All-Taxa Biodiversity Inventory (ATBI) inside the park. He, classmate Jimmy Webb and Dr. Ben Cash, professor of science, collected snakes, salamanders and turtles.

Nine years later, it would be a turtle that put Ennen's name among the annals of wildlife biology.

Printed in the June 2010 issue of Chelonian Conservation and Biology is Ennen's research that makes the case for a new turtle species endemic to the Pearl River drainage basin located in Louisiana and Mississippi. The name he's given the species is Graptemys pearlensis, or Pearl River Map Turtle.

Chelonian Conservation and Biology is an international journal of turtle and tortoise research. Co-authors of the paper – titled "Genetic and Morphological Variation Between Populations of the Pascagoula Map Turtle (Graptemys gibbonsi) in the Pearl and Pascagoula Rivers with Description of a New Species" – are biologists Jeffrey Lovich, Brian Kreiser, W. Selman and Carl Qualls.

"Of course, I never thought I'd name a species," said Ennen, who is now a wildlife biologist with the United States Geological Survey in Flagstaff, Ariz., "but my name will be attached to this species forever. I'm proud of what I've published."

A 1999 graduate of Maryville High School, Ennen is the son of Scott and Glenda Ennen of Maryville. He graduated from Maryville College in 2003, majoring in biology and playing on the men's basketball team. He went on to earn a master's degree in biology from Austin Peay State University. Last year, he finished his doctorate in biological sciences at the University of Southern Mississippi.

"This project [researching endemic turtles in the Pearl River drainage] was part of my dissertation at the University of Southern Mississippi," Ennen explained in a recent interview. "When I went there in 2005, I had a few ideas I wanted to research. I found a lab where I thought I'd fit in and soon met another student who was studying the Pascagoula Map Turtle. The species is found in only two rivers – the Pascagoula and Pearl – and I was curious about that."

Over time, Ennen and other biologists started documenting "significant but subtle differences" in the turtle species. These differences occurred in morphology (size and color and pattern of shells) and genetics.

The last turtle species discovered in the United States occurred in 1992 by Lovich, who is one of the co-authors of Ennen's study. With the discovery of Graptemys pearlensis, there are now 57 species of native turtles in the United States. Only 320 species have been found and documented worldwide.

"This discovery shows that even in well-studied countries like the United States, there are still new species of large vertebrates to discover," Ennen said, explaining that knowing what's out there is critical to protecting it, as well.

"The Pearl River Map Turtle is less abundant than the Ringed Map Turtle, and the Ringed Map Turtle is a federally listed threatened species," he explained, adding that it will be the decision of the U.S. Fish and Wildlife Service to add the Pearl River Map Turtle to its list of endangered species.

College provided strong foundation in biology

Ennen said his interest in ecology was sparked by a class taught in high school by David Ellis. Introduced to Dr. Cash, a herpetologist, while a freshman at Maryville College, Ennen found out about the ATBI and opportunities Maryville College students had to participate.

"That was definitely my start [in field biology]," Ennen said of the project.

In addition to the practical experience of finding and cataloging reptiles in the park, Ennen said he spent a lot of time with Cash, "talking science." Cash later involved Ennen in one of his independent research projects, which was studying the circadian calling dynamics of the wood frog, Rana sylvatica, whose habitats stretch from northern Alabama and Georgia to the edge of the Arctic Circle. The professor travels frequently to Manitoba, Canada, to conduct research at the Churchill Northern Studies Centre, and in the summer of 2003, Cash took Ennen north with him to study the frog.

When it came time for Ennen to pick a topic for his Senior Study, he chose to study the calling dynamics of the wood frog in the Great Smoky Mountain National Park.

"Dr. Cash just let me do it myself," Ennen said of the data collection and analysis. "It taught me how to be independent researcher, which was important."

Ennen said he felt extremely prepared for graduate school after he left Maryville. In addition to having several field biology experiences, he developed strong writing skills at the College and was mentored by Cash, who prepared him for the workload and standards of post-baccalaureate study.

"Dr. Cash told me how hard it would be," he remembered.

Cash said he isn't surprised that his former student's work is being published and discussed internationally.

"This is a 
great accomplishment for Josh, but not entirely unexpected," the professor said. "He has always excelled at what he loves, and he loves science – and turtles."

Cash remembered that Ennen showed a desire to be a field biologist as a freshman, so he looked for opportunities and ways to encourage the young student in that direction.

"My goal has always been to expose students to the complete picture of what science is all about, not just science in the classroom. In fact, that's where many students derive their passion – working in natural systems and interacting with the living world," Cash said.

Ennen is now working with Lovich, who has a grant from the California Energy Commission to look at how wind energy is affecting the desert tortoise, which is another threatened animal.

"What I like about being a scientist is whenever you answer a research question, there are always several more to be answered. It's a never-ending pursuit of knowledge, and it's always challenging and allows me to be creative," he said. "Maryville College and Dr. Cash introduced me to science and research, and I have built my career on that foundation."

Maryville College is ideally situated in Maryville, Tenn., between the Great Smoky Mountains National Park and Knoxville, the state's third largest city. Founded in 1819, it is the 12th oldest institution of higher learning in the South and maintains an affiliation with the Presbyterian Church (USA). Known for offering its students a rigorous and highly personal experience that includes an undergraduate research requirement, Maryville College is a nationally ranked institution of higher learning that successfully joins the liberal arts and professional preparation. Total enrollment for the fall 2016 semester is 1,198.