The Endangered Species Act (ESA) of 1973 was established to protect and conserve imperiled plant and animal species in the United States. More than 1,300 species are now listed as endangered or threatened under the ESA. A combination of the U.S. Fish and Wildlife Service (USFWS), U.S. Department of the Interior, National Oceanic and Atmospheric Administration (NOAA), other federal agencies, and numerous state organizations work in concert to maintain, regulate, enforce, and update the act.
The species on the ESA can be found throughout all of the country’s 50 states and territories. The distribution isn’t even, and there are definitely some surprises, like Tennessee.
The Volunteer State has an exceptionally high number of threatened or endangered species compared to most other states, with 131 — more than Texas and every other state not named Hawaii, Alabama, Florida, or California.
So keep reading to learn more about three endangered animal species that can be found (some more easily than others) in Tennessee today: the Barrens topminnow, gray bat, and Carolina northern flying squirrel.
Barrens Topminnow
Photo Courtesy G. Peebles/USFWS
The Barrens topminnow (Fundulus julisia) is a tiny fish endemic — native and confined within a specific area — to the springs and slower-moving streams of the Barrens Plateau in the middle of Tennessee. The fish have an average lifespan of two years and once populated a much wider range of land.
The unwelcomed introduction of invasive western mosquitofish that preyed on and harassed the Barrens topminnow drove the species to its current, limited habitat range. The fish was first petitioned to be listed as “endangered with critical habitat” under the ESA in 1977.
That attempt and a subsequent petition two years after the first would both fail to succeed in changing the species’ status — but roughly four decades later, another petition would find success.
USFWS determined that effective as of Nov. 20, 2019, the Barrens topminnow was officially an endangered species under the ESA.
The fish’s newfound status, not necessarily something other animals will be jealous of, gives federal and state agencies more power (and legal rights) to help protect them. And it’s already paying off! Just earlier this year, a new petition was submitted to USFWS proposing a designated critical habitat for the endangered fish. If accepted, the habitat would cover roughly 1.5 acres of spring pool and 11.5 miles of spring run across six counties in Tennessee.
Gray Bat
Photo Courtesy Cody Jordan
The gray bat (Myotis grisescens) is, in fact, not always gray. It does indeed have long, glossy, gray fur, but it can turn reddish-brown due to bleaching from the sun. The flying mammal’s current range includes parts of Tennessee and 16 additional states, and they are also known to occur in 10 different USFWS refuges. The species was officially designated as endangered under the ESA in 1976 and was added in a rather peculiar way.
On April 21, 1975, a proposal was put forth to list the gray bat as endangered. However, its status could not be determined until each governor of the proposal in every state where the species is known to occur was notified and given a 90-day window for the governors to comment.
The gray bat’s proposal was sent to the governors of 17 states where it was known to be found. The problem was that there was an 18th state: Oklahoma. That small miscommunication took roughly a year to correct, and the species has remained on the list as endangered ever since.
The bats are primarily threatened by human disturbances when they are hibernating, which can cause them to break from their sleep-like states and waste valuable energy meant to last them through the cold winter.
This threat is particularly dangerous for gray bats since an estimated 95% of the population hibernates in only 15 caves! The silver lining, of course, is that 14 of those 15 major hibernacula (caves) are considered permanently protected and gated off from the public. And no, that doesn’t mean you should go to the 15th.
Carolina Northern Flying Squirrel
Photo Courtesy Master Larry/USFWS
There are a lot of subspecies of flying squirrels. Like, way more than anyone not unusually knowledgeable about squirrels would ever guess. Case in point: The Carolina northern flying squirrel (Glaucomys sabrinus coloratus) is one of the 25 subspecies of northern flying squirrels in boreal coniferous and mixed coniferous/hardwood forests in the U.S. and Canada.
The long-named gliding mammal’s preferred habitat once stretched across much of North Carolina, Tennessee, and a few other states.
Over time, large-scale logging, other human-caused habitat destruction, and forest fires have diminished the squirrel’s range, limiting the species to a select few areas within.
Listed as endangered under the ESA in 1985, various organizations and agencies have tried to collect population data on the Carolina northern flying squirrels. In Tennessee, staff at the Cherokee National Forest have been monitoring nest boxes meant to capture and track the species, but those results have been fairly insubstantial.
The highest known population of the species left is currently in North Carolina. However, there are some promising signs that the populations in Tennessee and Virginia are larger than previously thought. Recently, instead of gathering data on the squirrels using nest boxes and other more traditional methods, some scientists and researchers have found promising data using acoustics.
By specifically monitoring the sounds coming near or around nest boxes, the unique piercing trills of the flying squirrel species can be identified. This effort opens up an entire world of possibilities that could, ultimately, lead to the Carolina northern flying squirrel getting off the list — in a good way.
