Armadillos, with their distinctive armored shells, are unique mammals native to the Americas. These creatures, which share ancestry with anteaters and sloths, possess an outer covering composed of bony plates. Primarily nocturnal, armadillos are now increasingly observed across various parts of the United States, including Tennessee.
Understanding Armadillo Expansion
The nine-banded armadillo, the only armadillo species found in the United States, began its expansion from its native habitats in South America. Historically, they were not found north of the Rio Grande before the mid-1800s. Their northward and eastward migration into the U.S. began around the 1850s from Texas and from Florida in the early 20th century, where some were inadvertently released.
Several factors contributed to this widespread movement. The reduction of natural barriers, such as fire-maintained grasslands, by European settlers allowed for easier dispersal. Human activities, including increased travel via roadways and railroads, also inadvertently accelerated their spread. Additionally, the species benefits from a high reproductive rate and a general lack of natural predators in many new territories.
The armadillo’s ability to adapt to diverse habitats, preferring moist, forested areas, further aided their expansion. While their poor tolerance for harsh winters and lack of insulating fat might limit their northernmost reach, their current rate of expansion is faster than that of many other mammals.
Tracing Their Arrival in Tennessee
Armadillos established populations in Tennessee during the mid-to-late 20th century. Reports indicate they were well-established in the far western parts of the state by the 1960s and 1970s, with initial sightings frequently occurring in the 1970s and 1980s.
Their entry into Tennessee likely occurred from neighboring states to the west, such as Arkansas and Mississippi. While early records were concentrated in the extreme southwest, new sightings from 2007 to 2011 in southeast Tennessee represented a range extension. These records, including those on the Cumberland Plateau, indicated movement beyond expected warmer, lower elevations.
By the early 1980s, armadillos were increasingly observed, establishing a permanent presence throughout the state by the 1990s. The first documented live armadillo within the Great Smoky Mountains National Park, at Newfound Gap, occurred in 2019, demonstrating their expansion into higher elevations. This surprised some scientists who initially believed colder, mountainous regions would deter them.
Armadillos Across Tennessee Today
Today, armadillos are widely distributed throughout Tennessee and are believed to inhabit every county. Their presence is no longer limited to the western regions. While sightings may still be less common in the most northeastern parts and mountainous areas like the Smoky Mountains, their range continues to extend.
Certain areas in Middle and West Tennessee, such as Williamson, Maury, Davidson, and Shelby counties, have become hotspots for armadillo populations. These animals demonstrate adaptability to various Tennessee landscapes, including suburban areas where they may dig for insects in well-watered lawns. This indicates their successful integration into diverse ecosystems across the state.