Wed May 14, 2014
Nobody Has Seen the Louisville Cave Beetle Since 1994, But It May Make the Endangered Species List
Scientists believe a beetle that has only be found in two caves near the south fork of Beargrass Creek may soon be protected under the Endangered Species Act.
And even though the Louisville Cave Beetle—the scientific name is Pseudanophthalmus troglodytes—hasn’t been seen since 1994, scientists say they have reason to believe it still exists.
"I have no reason to believe it doesn't exist," said Michael Floyd, an entomologist with the U.S. Fish and Wildlife Service.
The beetle was first discovered in 1964 in what is called Highbaugh Cave, but the entrance to that cave has since been destroyed because of construction, Floyd said.
More than 20 beetles were collected upon its first discovery, according to a study by the Kentucky State Nature Preserves Commission.
"That's a lot of beetles, so obviously it was doing pretty well," Floyd said.
He said the sealed entrance, however, causes some concern for the beetle’s potential for, well, not being extinct.
“The one downside to having the cave opening closed is that these cave systems are nutrient poor, there is no energy source or energy base for the ecosystem,” he said.
He said the closed entrance "basically disrupts the flow of energy and nutrients coming into the cave.”
The beetles are predators, Floyd said, which means to survive they need access to organisms that consume plant matter, such as millipedes.
“So, if there is no food base…there is nothing for the beetle to eat,” he said.
Despite the potential for a dwindling ecosystem, scientists remain hopeful for the beetle’s existence because of a few spottings of the beetle in Eleven Jones Cave at the edge of Cave Hill National Cemetery.
Floyd said researchers found at least two beetles in the Eleven Jones Cave in 1994, but he also added that “no one has really looked since then.”
In 2005, researchers said entering the Eleven Jones Cave—which is situated on the southwest bank of the South Fork of Beargrass Creek—is “likely to be unsafe” because of dangerously high amounts of carbon dioxide. That's kept researchers from conducting a full scale inspection of the cave.
How did the Louisville cave beetle get from one cave to the next? Whether Eleven Jones Cave connects to Highbaugh Cave is unknown, Floyd said.
When looking for the beetle, researchers would set traps or simply "turn over rocks," Floyd said. The beetles are most commonly found in late summer.
No other caves are known to support a population of the Louisville cave beetle, said the Kentucky State Nature Preserves Commission report.
The beetle has been a candidate for protection under the Endangered Species Act for years, and scientists hope it will gain new protections by 2017.
Floyd said the beetle was originally considered for listing due to habitat disturbances, vandalism and pollution to the watershed that drains into the cave.
He said there must be a threat to the species' continued existence to gain protection under the Endangered Species Act.
"Just rareness alone won't do it," he said. "There has to be threats, most of the time it is habitat loss."
And since the entrance to the cave the beetle was predominately found in was destroyed, the threat of habitat loss is seems to be a driving force behind ensuring the beetle gets protection.
The Kentucky Glade Cress, a small wildflower that can only be found in Jefferson and Bullitt counties, was recently added to a list of threatened species under the Endangered Species Act because of habitat loss.
The recommendations that have been made to protect the beetle include continuing to search for unknown caves in Jefferson County to survey any beetles found, and working to identify and eliminate the sources of pollution to Eleven Jones Cave, according to the Kentucky State Nature Preserves Commission.
Requests have also been made to restrict access to Eleven Jones Cave with a gate.