These students used Harp traps, high-frequency microphones, and recording units to search for the bats, whose numbers have decreased in the past few decades.
“When we began our work here, there were very few bats, simply a single bat or two,” Dr. Andrew Barrass, principal investigator for the Bat Project, said. “We have been working since 2005 to try and restore bat populations in the cave. In June 2006, the Dunbar Cave State Natural Area built a new ‘bat friendly’ cave entrance gate, and they were interested in us tracking the progression of bats slowly coming back into the cave.”
Since the project began, the students’ data shows a steady increase in a few bat populations. However, the species known as the ‘Little Brown bat’ has experienced a decline in population due to White Nose Syndrome (WNS), a fungal disease that has killed approximately five to seven million bats in North America in the past four years.
In 2010, then-graduate student Seth McCormick discovered a case of the disease in the cave. It was immediately closed off to the public, but students have been given access to the cave to continue their research.
Barrass said Tennessee’s Natural Areas program has asked the group to expand its work. The students are currently studying the effects of WNS on the agricultural economy because bats consume huge amounts of insects each year. A recent article in the journal “Science,” co-authored by University of Tennessee professor Gary F. McCracken, suggests that the “loss of bats in North America could lead to agricultural losses estimated at more than $3.7 billion/year.”
Aside from the Little Brown bat, other populations within the cave are increasing. “We haven’t had the mortality that most other sites have,” graduate student Veronica Mullen said. “We’ve also seen an increase in females. Their presence is more reproductively significant.” The group is hoping the cave closure will continue to boost numbers.
“It’s kind of sad,” former graduate student Josh Schulte said. “With White Nose Syndrome killing so many bats and seeing what the bats are going through, what if this is the one of the last opportunities we have to study these highly intelligent creatures?”
For more information on the bat research taking place at Dunbar Cave, contact the APSU Center of Excellence for Field Biology at 221-7019 or the Bat Project website at www.apsu.edu/bat.
Source: Clarksville Now